Chapter 2
Morphology,structure and
physiological function of
eukaryotes
Definition,eukaryotic cells are compartmentalized by membran-
es,The cell contains several different types of membrane bou- nd
organelle in which different biochemical and physiological
processes can occur in a regulated way,Membranes also transport
information,metabolic intermediats and end-products from the
site of biosynthesis to the site of use.
Eukaryotes is a big group of living organisms made up of
eukaryotic cells.with membrane bound nucleus and several
organelles such as mitochondrion etal.and divided by mitosis.真核生物是一大类细胞核具有核膜，能进行有丝分裂，细胞质中存在线粒体或同时存在叶绿体等多种细胞器的生物,
eukaryotic micro-organisms is a group of Microorganisms that made
up of eukaryotic cells include Fungi,microalgae（）,and protozoa
真核细胞真核生物真核微生物
peroxisomes
mitochondrion
cytosol
chloroplast
Smooth endoplasmic
reticulum
Structure of a typical plant cell
Cytosol细胞液Plasma membraneSecretory vesicles
Structure of a typical animal cell
membraneCell wall
mitochondrion
Vesicals (泡囊 )
Dictyosomes (分散高尔基体 )
Hyphal structures
Endoplasmic reticlum
ribosomes
membrane
vacuole
Cell wallmitochondrion
Nucleus
Endoplasmic
reticulum
Yeast structures
Yeast structures
真核微生物主要包括菌物界 (Mycetalia或广义的,Fungi”)中的真菌 (Eumycota或狭义的
,Fungi”，即 True Fungi)、
粘菌 (Myxomycota或 Fungi— like Protozoa)、
假菌 (Chromista或 Pseudofungi)，
植物界 (Plantae)中的显微藻类 (Algae)和动物界 (Animalia)中的原生动物 (Protozoa)
Major groups of eukaryotic microorganisms
真核微生物的主要类群植物界 （ plantae）：显微藻类 algae
动物界（ animalia）：原生动物 protozoa
真核微生物黏菌 myxomycota
假菌 pseudofungi
菌物界（ mycetalia）
单细胞真菌 unicellular fungi
真菌 eumycota 丝状真菌 filamentous
大型子实体 蕈菌 mushroom
Major groups of eukaryotic microorganisms
Eukaryotic
microorganisms
,菌物界 ’’ 这个名词是我国学者裘维蕃等于
1990年提出的，并已 ·得到学术界的一定支持，
这是指与动物界、植物界相并列的一大群无叶绿素、依靠细胞表面吸收有机养料、细胞壁一般含有几丁质的真核微生物。一般包括真菌、
粘菌和假菌 (卵菌等 )3类。
真菌是最重要的真核微生物，故是本章的重点，它们的特点是：
① 无叶绿素，不能进行光合作用；
② 一般具有发达的菌丝体；
③ 细胞壁多数含几丁质；
④ 营养方式为异养吸收型；
⑤ 以产生大量无性和 (或 )有性孢子的方式进行繁殖；
⑥ 陆生性较强
Fungi are filamentous,non-photosynthetic,
eukaryotic microorganisms that have a heterotrophic
nutrition,Their basic cellular unit is described as a
hypha,This is a tubular cell which is surrounded by
a rigid,chitin-containing cell wall,The hypha extends
by tip growth,and multiplies by branching,creating a
fine network called a mycelium,Hyphae contain
nuclei,mitochondria,ribosomes,Golgi and
membrane-bound vesicles within a plasma-
membrane bound cytoplasm,
The subcellular structures are supported and
organized by microtubules and endoplasmic
reticulum,The cytoplasmic contents of the hypha
tend to be concentrated towards the growing tip,
Older parts of the hypha are heavily vacuolated and
may be separated from the younger areas by cross
walls called septae,Not all fungi are multicellular,
some are unicellular and are termed yeasts,These
grow by binary fission or budding,creating new
individuals from the parent cell.
Mould （ Mold）
Definition
Mold are filamentous,nonphotosynthetic,
eukaryotic microorganisms that have a
heterotrophic nutrition（ filamentous fungi）。
Morphology and structure
Hypha and mycelium菌丝与菌丝体
lower fungi—— non-septate mycelium
s higher fungi—— septate mycelium with elaborate,perforate
septa
The hypha extends by tip growth,and multiplies by branching,creating a
fine network called a mycelium,（ plural mycelia）
Mycelia can be divided into vegatative mycelium and aerial mycelium（营养菌丝体和气生菌丝体）
Basic unit—— hypha（ pl。 hyphae） This is a tubular cell which is
surrounded by a rigid,chitin-containing cell wall,Hyphae contain nuclei,
mitochondria,ribosomes,Golgi and membrane-bound vesicles within a
plasma-membrane bound cytoplasm
membrane Cell wall
mitochondrion
Vesicals
Dictyosomes
(分散高尔基体 )
Hyphal structures
Specialized morphology of vegetative mycelium
营养菌丝体的特化形态
Rhizoid 假根 —— Rhizopus
Stolon 匍匐菌丝 —— Mucorales,Rhizopus
Haustorium 吸器
Adhesive cell 附着胞
Adhesive branch 附着枝
Sclerotium 菌核
Rhizomorph,funiculus菌索
ring and net 菌环和菌网
1)假根 (rhizoid) 是 Rhizopus(根霉属 )等低等真菌匍匐菌丝与固体基质接触处分化出来的根状结构，具有固着和吸取养料等功能
(2)匍匐菌丝 (stolon)又称匍匐枝。毛霉目 (Mueorales)真菌在固体基质上常形成与表面平行、具有延伸功能的菌丝，称匍匐菌丝。最典型的可在 Rhizopus中见：在固体基质表面的营养菌丝分化为匍匐菌丝，在其上每隔一段距离可长出伸人基质的假根 根霉的形态和构造和伸向空间的孢囊梗，
随着匍匐菌丝的延伸，不断形成新的假根和孢囊梗，这类真菌会随基质的存在而向四处快速蔓延，根本就不会形成像在其他真菌中常见的那样有固定大小和形态的菌落。
sporangium
(3)吸器 (haustorium) 由几类专性寄生的真菌如锈菌目
(Uredinales)、霜霉目 (Peronosporales)和白粉菌目
(Erysiphales)等的一些种所产生。吸器是一种只在宿主细胞间隙间蔓延的营养菌丝上分化出来的短枝，它可侵入细胞内形成指状、球状或丝状的构造，用以吸取宿主细胞内的养料而不使其致死。
(4)附着胞 (adhesive cell) 许多寄生于植物的真菌在其芽管或老菌丝顶端会发产 膨大，分泌粘状物，借以牢固地粘附在宿主的表面，此即附着胞。在其上再形成针状感染菌丝，以侵入宿主的角质表皮而吸取养料。
(5)附着枝 (adhesive branch) 若干寄生真菌由菌丝细胞生出
1— 2个细胞的短枝，将菌丝附着于宿主体上，
（ 6）菌核（ sclerotium) 是一种形状、大小不一的休眠菌丝组织，在不良外界条件下：可保存数年生命力。菌核形状有大有小，大的如茯苓 (大如小孩头 )，
小的如油菜菌核 (形如鼠粪）。菌核的外层色深、坚硬、内层疏松，大多呈白色。
（ 7）菌索（）一般由伞菌等产生，为白色根状菌丝组织，功能为促进菌体蔓延和抵御不良环境。通常可在腐朽的树皮下和地下发现。
(8)菌环 (loop )和菌网 ( net) 捕虫菌目 (zoopasdes)
和一些半知菌的菌丝常会分化成圈环或网状的特化菌丝组织，用以捕捉线虫或其他微小动物，然后进一步从这类环或网上生出菌丝侵入线虫等体内，吸收养料
（ 9）子实体（ fruiting body,sporocarp，
fructification）
Colonial growth
Hyphal tip growth allows fungi to extend into new regions from a
point source or inoculum(接种物 ),Older parts of the hyphae are
often emptied of contents as the cytoplasm is taken forwards with
the growing tip,(老的菌丝通常缺乏内含物，因为细胞质流向生长点 )This creates the radiating colonial pattern seen on agar plates,
in ringworm infections of skin and fairy rings in grass lawns,Only
hyphal tips contribute to extension growth,However older hyphae
can grow aerially or differentiate to produce sporing structures（只有菌丝顶端对延伸生长起作用，而老菌丝可以进行气生生长或分化出产孢子的结构）
Mycelium
in agar
Agar
Surface
mycelium
Kinetics of growth
Fungal growth in a given medium follows the growth phases of
lag,acceleration,exponential,linear,retardation,stationary and
decline（延迟期、加速期、指数期、直线期、减速期、稳定期、衰亡期）,Exponential growth occurs only for a brief period as hyphae
branches initiated,and then the new hypha extends at a linear rate
into uncolonized regions of substrate,
Life cycles All fungi are characterized by
having a period of vegetative growth where their
biomass increases,The length of time and the
amount of biomass needed before sporulation can
occur varies,Almost all fungi reproduce by the
production of spores,but a few have lost all sporing
structures and are referred to as mycelia sterilia(不育菌丝体 ),Different types of spore are produced in
different parts of the life cycle.
Reproduction in fungi
All fungi undergo a period of
vegetative growth where their
mycelium exploits a substrate,
This stage is followed by asexual
and sexual reproduction.
.
There are two conflicting requirements fungi have for their
spores,Spores must allow fungi to spread,but they must also
allow them to survive adverse condi tions,These requirements
are met by different types of spores,Small,light spores are
carried furthest from parent mycelium in air and these are the
dispersal spores（释放型孢子）,They are usually the products of
asexual sporulation,the sporangiospores and the conidiospores,
and so spread genetically identical individuals as widely as
possible,Genetic diversity is maintained by sexual reproduction,
and the spore products are often large resting spores（休眠孢子）
that withstand adverse conditions but remain close to their site of
formation,Spores therefore vary greatly is size,shape and
ornamentation,and this variation reflects specialization of
purpose.
Fungal spores,spores allow
fungi to spread,to maintain
genetic diversity and to survive
adverse conditions
spore discharge,Spores that have a
dispersal function can be released from their parent
mycelium by active or passive mechanisms,As
many spores are wind dispersed,they are produced
in dry friable masses which are passively
discharged by wind,Other spores are passively
discharged by water droplets splashing spores
away from parent mycelium.
Spores may be discharged from
parent mycelium by passive or active
means,Passive mechanisms include
using wind and water as dispersants;
active mechanisms use explosive
principles.
Spores in the atmosphere（ air-borne fungal
spores） can be carried great distances。 Their
presence in the air can have impact on human
health as they can cause allergic rhinitus （ hay
fever） and asthma。 Many plant diseases that
cause great economic losses are air borne。 can
affect human,animal and plant health,They can
cause allergies and spread plant disease.
Air spora
Fungi reproduce by the formation of sexual or asexual
spores
Asexual reproduction
fission
Arthrospore
Budding
blastospore
Other asexual spore
Zoospore
Chlamydospore
Sporangiospore
conidiospora
Sexual reproduction
Oospore
Zygospore
Ascospore
Basidiospore
节孢子 (arthrospore)
某些真菌生长到一定阶段，菌丝中间形成许多隔膜，接着从隔膜处断裂成许多竹节似的无性孢子，称为节孢子，也称为粉孢子。最典型的例于是白地霉
(Geotrichumcandidum
).
arthrospore
Blastospore (芽孢子 )这和酵母菌的出芽一样，它是由母细胞生芽而形成的。当芽长到正常大小时，脱离母细胞，或仍连在母细胞上。
如玉蜀黍黑粉菌
(Ustilago maydis)
能产生芽孢子。某些毛霉或根霉在液体培养基中形成的被称为酵母型细胞，也属芽孢子。
又称厚壁孢子或厚膜孢子。某些真菌生长到 — 定阶段，在菌丝的顶端或中间有部分细胞的细胞质密集在一起，变圆，然后在其四周生出厚壁，或原细胞壁加厚，形成圆形、纺锤形的无性休眠体，来抵抗外界不良的环境条件。例如总状毛霉 (Mucor racemosus)往往在菌丝中间形成许多厚垣孢子
schlamydospore（厚垣孢子）
无性繁殖产生的孢子在孢子囊 (Sporange)内,孢子囊一般生在气生菌丝的顶端或生在孢囊梗 (sporangiophore)的顶端。
在形成孢子囊前，首先有多核的原生质密集于此处，使其膨大，并在下方生出横隔，形成圆形的囊状物，然后其中原生质体割裂成许多小块，每 — 块发育成为 — 个孢子囊孢子。因而每一 ·个孢子囊所含有的孢子的数 — 般都相当多。
就孢子囊孢子而言,— 般有二类,一种具有 — 根或 2~3根鞭毛，能够游动，所以称游动孢子 (zoospore)。例如腐霉
(即 thium)。另一种无鞭毛，不能游动，又称静止担于。
sporangiospore (孢子囊孢子 )
游动孢子
conidium (分生孢子 )
分生孢子的形成方法其形成方式有两种，一种是在分生孢子梗的顶端突出，发育成第一个孢子。梗再伸长形成第二个孢子，如此重复形成一串孢子。这样形成的分生孢子，顶端的最老。曲霉属和青霉届的分生孢子形成，即属于此类型。
另一种是在第 — 个分生孢子形成时，柄的长度已达到最高，由第一个分生孢子顶端生长出第二个分生孢子，如此重复形成一串孢子。
这样形成的分生孢子，下部的最老。如枝孢霉属 (Cladosporium)的分生孢子形成即属于此类型。
Plastic kitchen cutting board surface - rod
bacteria in a smooth matrix; filamentous
bacteria ( 丝状菌 ) -smooth oval cells;
fungal hyphae ( 真菌菌丝 ) with textured
spores ( 结构孢子 ) (x 2,270)
conidium
Zoospore（游动孢子）
Asexual spore,usually
produced by fungi living
in water,Motile
zoospores in motile
sporangia differentiated
from swelled hyphal tips
have a single posterior
flagellum。 The structure
of the flagellum is 9+2,
some has two flagella.
霉菌的有性繁殖是经过不同性别的细胞结合 (质配和核配 )后，产生一定形态的孢子来实现的，这种孢子称为有性孢子。繁殖过程可分为三个阶段：第 — 个阶段为质配；第二个阶段为核配，产生二倍体的核；第三个阶段是减数分裂，恢复核的单倍体状态。大多数真菌菌体是单倍体的。有性孢子通常有下列几种：
Sexual reproduction
菌丝分为雄器
(antheridium)和藏卵器 (oogonium)。藏卵器中有一个或数个卵球
(oosphere)。当雄器和藏卵器相配时，雄器中细胞质与细胞核，通过受精管而进入藏卵器，
与卵球结合形成卵孢子。
图所示是德巴利腐霉的卵孢子的形成。
oospore (卵孢子 )
（ b）同宗结合（ a）异宗结合根霉的接合孢子
Zygospore（接合孢子）
ascospore （子囊孢子）
形成子囊孢子是子囊菌的主要特征。子囊中孢子数目通常为 1~8个，或为 2n。典型的子囊中有 8个孢子。大多数霉菌的子囊是包裹在子囊果（ ascocarp）中。
子囊果有三种类型 子囊壳 perithecium 子囊盘 apothecium
闭囊壳 cleistothecium
Sexual reproduction in this group occurs after somatic fusion of
different mating-type mycelia,A transient diploid phase is rapidly
followed by the formation of ascospores within sac-shaped asci
differentiated from modified hyphal tips,In the initial stages of ascal
development hooked hyphal tips form,called croziers （产囊丝钩）
or shepherds‘ crooks（牧羊杖） because of their shape,They have
distinctive septae at their base which insure that two different
mating-type nuclei are main tained in the terminal cell,Formation of
the septae is coordinated with nuclear division,In yeasts all these
events occur within one cell,after fusion of two mating-type cells,
the whole cell being converted into an ascus.
The formation of ascospores
Sexual reproduction in the ascomycetes
In more complex Ascomycetes many asci form together,creating a
fertile tissue called a hymenium（叫子实层的能育组织）,In some
groups the hymeniumcan be supported or even enclosed by large
amounts of vegetative mycelium,The whole structure is called a
fruit body or sporocarp（子囊果） and is used as a major taxonomic
feature,They can become large enough to be seen with the naked
eye,Flask-shaped sexual reproductive bodies are called perithecia,
cup-shaped bodies are called apothecia and closed bodies are
called cleistothecia,These structures have evolved to protect the
asci in spore dispersal,but the hymenium itself is unafected by the
presence of water。
The formation of sporocarp
and its forms
Cup-shaped
apothecium
Flask-shaped
perithecium
Closed
cleistothecium
Asci
Asci
Ascus
containing
ascospores
Basidiomycete fungi rarely reproduce asexually,Sexual reproduction
is by the formation of basidiospores on the gills or pores of large fruit
bodies.This group of fungi are characterized by the most complex
and large structures found in the fungi,They are also distinctive in
that they very rarely produce asexual spores,Much of the life cycle is
spent as vegetative mycelium,exploiting complex substrates,A
preliminary requisite for the onset of sexual reproduction is the
acquisition of two mating types of nuclei by the fusion of compatible
hyphae,Single representatives of the two mating-type nuclei are held
within every hyphal compartment for extended periods of time,This is
termed a dikaryotic state（双核期）,and its maintenance requires
elaborate septum formation during growth and nuclear division,
Basidiospore
Onset of sexual-spore formation is triggered by
environmental conditions and begins with the formation of a
fruit body primordium（子实体原基）,Dikaryotic mycelium
（双核菌丝体） expands and differentiates to form the large
fruit bodies we recognize as mushrooms and toadstools（毒蕈）,Diploid formation and meiosis occur within a modified
hyphal tip called a basidium 。
Basidium formation
核融合
Nuclear fusion 减数分裂meiosis
担孢子梗
sterigmata
Basidio
spores
担孢子
Basidium
（担子）
Basidium and basidiospore
formation
Four spores are budded from the basidium,Basidia form
together to create a hymenium which is highly sensitive
to the presence of free water,The hym-enium is
distributed over sterile,dikaryotic supporting tissues
which protect it from rain,The hymenium can be exposed
on gills or pores beneath the fruit body,seen in the
toadstools and bracket fungi,or enclosed within
chambers as in the puffballs and truffles
Formation of
basidiospore
puffball （马勃）
Bracket
（檐状伞）
Toadstool
（毒蘑菇） Hymenenium
（子实层）
Structure of sexual sporocarps in the basidiomycetes
basidiospore（担孢子）
担孢子是担子菌特有的特征。它是一种外生孢子，
经过两性细胞核配合后产生。因为它生在担子上，
所以称为担孢子。典型的担子菌的担子上有四个担孢子。
各种担孢子的形状及表面特征
Food related molds
1,Aspergillus 曲霉属
2,penicillium（青霉属 ）
3,Rhizopus （根霉属）
4,sporotrichum (侧孢霉属 )
5,Thamnidium(枝霉属 )
6,Alternaria（交链孢属）
7.Botrytis （葡萄孢霉）
8.Trichoderma（木霉属）
9.Monascus（红曲属）
10.Gibberella（赤霉属）
11.Cordyceps（虫草属）
12.geotrichum（地霉属）
13.helminthosporium（长蠕孢霉）
food related Moulds Aspergillus曲霉属分生孢子初生小梗孢子穗 小梗次生小梗顶囊足细胞
Conidia
primary sterigma
conidial head sterigme
secondary sterigma
Vesicle
foot cell
Morphology of Conidial head is the basis for species identification
孢子穗的形态是菌种鉴定的依据
Aspergillus
Relationship with food—— beneficial
Fermentation industry
soy sauce酿酱
vinegar制醋曲
fermented bean curd腐乳
alcohol beverage酿酒
Food processing
organic acid有机酸
enzyme 酶制剂淀粉酶蛋白酶果胶酶等
Relationship with food—— harmful
Usually distributed on the surface of following foodstuff：
Cakes,fruits,vegetables,meat,grain and other
organic objects。
Causing following consequences：
Go mouldy； become mildewed
Produce or secrete carcinogenic
substance（ blastomogen）致癌物质
eg 。 aflatoxin（黄曲霉毒素）
Food related molds—— penicillium（青霉属 ）
十分接近于曲霉，在自然界分布很广，长生长在腐烂的柑橘皮上，呈青绿色，不少种类引起食品变质，但也用来生产青霉素和有机酸等。
青霉菌菌丝与曲霉相似，但无足细胞，孢子穗结构也不同。
其分生孢子梗顶端不膨大，而是经过多次分枝产生几轮对称或不对称的小梗，然后在小梗的顶端产生成串的分生孢子。青霉菌的孢子穗形状似扫帚状。分生孢子球形、椭圆形或短柱形，
一般呈蓝绿色。
Plastic kitchen cutting board surface - rod bacteria in a
smooth matrix; filamentous bacteria ( 丝状菌 ) -smooth oval
cells; fungal hyphae ( 真菌菌丝 ) with textured spores ( 结构孢子 ) (x 2,270)
根霉在自然界分布广泛，经常出现在淀粉质食品上，引起粮食、
食品腐烂、腐败。 I工业上常利用根霉生产糖化酶，甜酒曲中主要菌种也是根霉。此外，根霉也可以用来生产有机酸等其它物质。
Food related molds—— Rhizopus （根霉属）
Rhizoid
假根
Stolen
匍匐丝
sporange
Uaually black
sporangiophore
菌丝分隔 ·分生孢子梗分枝，顶端产生分生孢子。分生孢子单细胞，梨形。菌落呈奶油色泽，时间长后，为干燥粉末状。
已经报告该菌能在 O~C以下生长，常在冷藏肉中形成白色斑点。
food related molds— sporotrichum (侧孢霉属 )
S,Carnis
肉色侧孢霉
Conidium
分生孢子
Conidiophore
分生孢子梗
Cause the deterioration of
vegetables and fruit
conidium
conidiophore
形状大小不定，数个连接成链，暗褐色，有纵横隔膜，
呈壁砖状 。
大多数不分支，较短，单生或成簇，
暗褐色。
Food related molds—— Alternaria（交链孢属）
septate mycelium
Food related molds—— Botrytis （葡萄孢霉）
conidiophore
conidium
分生孢子梗顶端形成树枝状分支，分支顶端细胞常常膨大，
在短的小梗上着生分生孢子，
如一串葡萄。
卵圆形，无色或暗褐色。
常产生外形不规则的黑色菌核（ sclerotium）。
分布在许多植物和植物食品上，形成一层“灰色霉”，
引起水果、蔬菜的腐败。
Food related molds—— Trichoderma（木霉属）
Spherical or elliptical
（ oval）,smmoth or
rough,yellow-green
conidia
Colorless hypha,with septa and branches,
produce chlamydospores
Bottle-like
sterigme
瓶状小梗
Spore head gathered
（ conglutenated） by mucus
（ slime）
Food related molds—— Trichoderma（木霉属）
Colony grows rapidly,like cotton fibre（棉絮状），
white at first,later become green。 Spore-producing
area takes on（ has） concentric circles
Sone species has cellulolytic activity,therefore can
be used to produce cellulase to manufacture sugars
with cellular waste（下脚）,starch processing and
food processing
Moldy grain,fruit and
vegetables
Mildew and rot of cellular
material。
Food related molds—— Monascus（红曲属）
Can secrete red pigment
The source of natural red pigment in the food
processing,for instance red rice（ ang-kak）
used in the processing of red fermented bean
curd,bevarage and meat is prepared from
Monascus。
Type culture that commonly
used,M,purpureus（紫红曲）
Food related molds—— Monascus（红曲属）
Colony features,membranous colony covers
the whole malt extract plate,mycelium is
white at first,later becomes red,red-purple，
the water-soluble pigments are secreted into
the medium。
conidium
Food related molds—— Monascus（红曲属）
1~3 initiate
cleistothecium
4~5 premature
cleistothecium
6 mature
cleistothecium
cleistothecium of M.purpureus
紫红曲的闭囊壳
Food related molds—— Gibberella（赤霉属）
reproduction
scarcely produce Sexual generatin （ gamobium,sexual
progeny）,sexual spore is ascospore in spherical,smooth
and blue perithecium（子囊壳）。
Asexual reproduction produce two types of conidium
Small type,single
cellular,spherical，
elliptical to long
column,colorless or
other colors
Large type：
multicellular
with septa，
Sickle-like or
long column，
Colorless or
other colors
Food related molds—— Gibberella（赤霉属）
Gibberellin or abbeymycin （赤霉素）
Metabolic product of Gibberella,is a kind of hormone
with the following function：
1.Stimulate plant growth
2.Break the dormancy of seed and tuber
3.Increase the yield of vegetables especially leafy
vegetables
Food related molds—— Cordyceps（虫草属）
Formation,The insect body parasitized by the fungi was full of
mycelium（ sclerotium 菌核） and mummified,stem-head like or
rod like stroma （ plural stromata 子座） grows out from its front
end。
Inchworm
尺蠖
Stroma （ grass）
usually single，
scarcely 2 or 3，
4~11cm in length。
perithecium
Ascus
（ asci）
ascospore
Cordyceps sinesis冬虫夏草
Food related molds—— geotrichum（地霉属）
Reproduction by fission,septate hypha,hypha may break
into arthrospore,without blastospore。
Always existed in sauerkraut（ kimchi,pickles泡菜），
fecund,organic fertilizer,rotten fruit and vegetables and
other plant residues。
Arthrospore
germination
Hypha breaks into
fragment----arthrospore
G,Candidum (白地霉 )
Food related molds—— helminthosporium（ 长蠕孢霉 ）
conidiophore
conidium
Colorless or gray septate mycelium,septate
conidiophore,conidium is black-gray,usually has
4~6 cells,many fungi of the genera are both
parasite and saprobe （ saprophytic bacterium，
saprogen,saprotroph，腐生菌）
Food related molds—— geotrichum（地霉属）
Some species has high nutritional value,has
the following usages:
1,Edible or as forage supplement
2,Nucleic acid extraction
3,Fat synthesis
G.candidum
Eukaryote—— yeast
Definition,yeast is a group of
unicelled eukaryotic microorganisms
reproduced by budding,Generally it
refers to all single-celled eukaryotes
that can ferment carbohydrates.
Eukaryote—— yeast
It‘s a kind of microbes utilized early by human
being,Mainly exists in the acidic environment
with high sugar content such as on the fruits，
vegetables,flower honey and confect,or in
the orchard soil,Most yeasts are saprophyte and
beneficial to human being,only a few are
parasitism and can cause the human being，
plant and animal diseases,Some yeasts can lead
to the deterioration of fruit juice,jam,honey，
alcohol beverage,and meat.
Yeast cell morphology and structure
Most yeast are unicell usually are spherical,oval
or column shape,some species may form lotus
root shaped pseudomycelium,
Diagram of yeast cell structure
Saccharomyces
cerevisiae is the
most typical and
the most important
yeast,The figure
right shows its cell
structure.
membrane
vacuole
Cell wallmitochondrion
Nucleus
Endoplasmic
reticulum
The major components of yeast cell wall are glucan（葡聚糖） and
mannan（甘露聚糖）,and different amount of proteins,lipids
and chitin （几丁质）,Infant cells has homologous cytoplasm，
later vacuole emerged,
Yeast structures
Colonial morphology
Like bacterial colonies,yeast colony has following features：
wettish （ humid）,a little transparent,with lubricous （光滑的
slippery） surface and even texture and can be easily picked up，
the obverse side and the reverso side,the edge and the center
has the same color,Other hand,it is bigger,thicker,denser，
and a little opaque than that of bacterium,Compared with
bacteria,its colony only has several colors,normally is milk
white or candle white（矿烛色）,few are red,one or two is
black,Those without pseudomycelium has bulged colony with
round edge,while Candida has the flat colony with coarse
brink and surface.
Reproduction of yeast
Budding,by all yeasts
Asexual fission,by schizosaccharomycetes
arthrospore
Asexual sporulation ballistospore
chlamydospore
Sexual,by formation of ascus and ascospore
Budding
When yeast grows on a plate of rich nutrition and under optimal
culture condition,it multiply rapidly,nearly all cells are
budding,therefore,conglomerated into cell clusters（ balls）,
After a series of budding,if daughter yeasts don‘t depart from
parent cells,and only linked by narrow and small area,thus
formed lotus root shaped cell strings called pseudohyphae.
Pseudohyphae and euhyphae
Otherwise,cells linked and the septa area is the same as cell
diameter formed laemodipodiform（竹节形） cell strings,that
is called euhyphae euhyphae 。
When daughter yeast depart from the parent cell,Scar was
leaved on both of them,called bud scar（ on parent cell） and
birth scar（ on daughter cell） respectively.
Bud scar and birth scar
光学显微镜下看到的酵母细胞这里显示的菌种 是用来发面团以及将葡萄汁转变成酒的那些细胞。他们繁殖时先出芽，进而不对称分裂为一大一小两个子细胞酿酒酵母
（ saccharomyces cerevisiae）
Food related yeasts(1)——
saccharomyces （ 酵母属 ）
Saccharomyces widely colonized on fruits and
vegetables,orchard and seed yeast （酒曲）,
Spherical,elliptical,sausage-shaped reproduced by
multi-ends budding or sexually producing 1~4
ascospores,Strong fermentative ability,major
products are ethonal and co2,Can‘t use lactose and
high-level hydrocarbon（烃类 ).
features
Many species are widely used in industry,for
instance S,cerevisiae（酿酒酵母） can be used in
brewing of beer,alcohol and other beverages，
as well as bread making.
Beneficial
Some cause the fruit and vegetable fermentation，
therefore cause food decay,For example S.rouxii （鲁氏毛霉） and S,Melliscan（蜂蜜酵母） are tolerant to
sugar solution of high concentration cause the
spoilage or deterioration of jam and other foods,They
can also survive in high concentrative salt solution，
live in soy sauce and form a layer of gray-white，
powder-like pellicle,thus affect the quality of soy
sauce.
Detrimental
酿酒酵母的光镜照片
Saccharomyces cerevisiae 酿酒酵母 SEM
10μm
Food related yeasts
（ 2） Brettanomyces （酒香酵母属）
Some species involved in the post-fermentative period in the
brewing of some Europe beers.
Some other species can be isolated from deteriorated Kraut,
fruits and vegetables.
（ 3） Candida （假丝酵母属）
Normally exists on the surface of fresh and salted meat
and other many foods.
Food related yeasts
(4)Debaromyces （德巴利酵母属 ）
Usually can be isolated from the flowing deteriorated food：
meat,sausage and alcohol beverages.
(5)Endomycopsis（拟内酵母属 ）
Form euhyphae and usually form a thin layer of pellicle,can be
detected from flowing foods,grains,fermented sauerkraut or
cucumber and Some species can be used to produce αandβ amylase.
(6)Hansenula （汉逊酵母属）
Usually formed pseudohyphae,grows on oranges,grape
and the their product or condensed juice.
Food related yeasts
(7) Kloeckera （克勒克酵母属）
This group can both involve in the fermentation and oxidation,
usually grows on fruit the contaminated by the fruit flies,Some
species can leads to the abnormal smell or turbidity of alcoholic
beverages,
(8)Mycoderma（醭酵母属）
Form a thick layer of mycoderm（ pellicle） floated above the
beer,vinegar,sauerkraut,fruit juice and their product.
Food related yeasts
(10)Rhodotorula（红酵母属）
Widely existed in the environment,many can produce red
pigment on food or medium,Some species can cause human
and animal diseases.
(9)Pichia （毕赤氏酵母属）
Contaminative fungi of alcohol industry,always form a
layer of white,dry pellicle,Many species can form
pseudohyphae and produce ascospore,has weak ability of
catalyzing (assimilating) carbohydrates,don’t produce
ethonal.
Morphology,structure and
physiological function of
eukaryotes
Definition,eukaryotic cells are compartmentalized by membran-
es,The cell contains several different types of membrane bou- nd
organelle in which different biochemical and physiological
processes can occur in a regulated way,Membranes also transport
information,metabolic intermediats and end-products from the
site of biosynthesis to the site of use.
Eukaryotes is a big group of living organisms made up of
eukaryotic cells.with membrane bound nucleus and several
organelles such as mitochondrion etal.and divided by mitosis.真核生物是一大类细胞核具有核膜，能进行有丝分裂，细胞质中存在线粒体或同时存在叶绿体等多种细胞器的生物,
eukaryotic micro-organisms is a group of Microorganisms that made
up of eukaryotic cells include Fungi,microalgae（）,and protozoa
真核细胞真核生物真核微生物
peroxisomes
mitochondrion
cytosol
chloroplast
Smooth endoplasmic
reticulum
Structure of a typical plant cell
Cytosol细胞液Plasma membraneSecretory vesicles
Structure of a typical animal cell
membraneCell wall
mitochondrion
Vesicals (泡囊 )
Dictyosomes (分散高尔基体 )
Hyphal structures
Endoplasmic reticlum
ribosomes
membrane
vacuole
Cell wallmitochondrion
Nucleus
Endoplasmic
reticulum
Yeast structures
Yeast structures
真核微生物主要包括菌物界 (Mycetalia或广义的,Fungi”)中的真菌 (Eumycota或狭义的
,Fungi”，即 True Fungi)、
粘菌 (Myxomycota或 Fungi— like Protozoa)、
假菌 (Chromista或 Pseudofungi)，
植物界 (Plantae)中的显微藻类 (Algae)和动物界 (Animalia)中的原生动物 (Protozoa)
Major groups of eukaryotic microorganisms
真核微生物的主要类群植物界 （ plantae）：显微藻类 algae
动物界（ animalia）：原生动物 protozoa
真核微生物黏菌 myxomycota
假菌 pseudofungi
菌物界（ mycetalia）
单细胞真菌 unicellular fungi
真菌 eumycota 丝状真菌 filamentous
大型子实体 蕈菌 mushroom
Major groups of eukaryotic microorganisms
Eukaryotic
microorganisms
,菌物界 ’’ 这个名词是我国学者裘维蕃等于
1990年提出的，并已 ·得到学术界的一定支持，
这是指与动物界、植物界相并列的一大群无叶绿素、依靠细胞表面吸收有机养料、细胞壁一般含有几丁质的真核微生物。一般包括真菌、
粘菌和假菌 (卵菌等 )3类。
真菌是最重要的真核微生物，故是本章的重点，它们的特点是：
① 无叶绿素，不能进行光合作用；
② 一般具有发达的菌丝体；
③ 细胞壁多数含几丁质；
④ 营养方式为异养吸收型；
⑤ 以产生大量无性和 (或 )有性孢子的方式进行繁殖；
⑥ 陆生性较强
Fungi are filamentous,non-photosynthetic,
eukaryotic microorganisms that have a heterotrophic
nutrition,Their basic cellular unit is described as a
hypha,This is a tubular cell which is surrounded by
a rigid,chitin-containing cell wall,The hypha extends
by tip growth,and multiplies by branching,creating a
fine network called a mycelium,Hyphae contain
nuclei,mitochondria,ribosomes,Golgi and
membrane-bound vesicles within a plasma-
membrane bound cytoplasm,
The subcellular structures are supported and
organized by microtubules and endoplasmic
reticulum,The cytoplasmic contents of the hypha
tend to be concentrated towards the growing tip,
Older parts of the hypha are heavily vacuolated and
may be separated from the younger areas by cross
walls called septae,Not all fungi are multicellular,
some are unicellular and are termed yeasts,These
grow by binary fission or budding,creating new
individuals from the parent cell.
Mould （ Mold）
Definition
Mold are filamentous,nonphotosynthetic,
eukaryotic microorganisms that have a
heterotrophic nutrition（ filamentous fungi）。
Morphology and structure
Hypha and mycelium菌丝与菌丝体
lower fungi—— non-septate mycelium
s higher fungi—— septate mycelium with elaborate,perforate
septa
The hypha extends by tip growth,and multiplies by branching,creating a
fine network called a mycelium,（ plural mycelia）
Mycelia can be divided into vegatative mycelium and aerial mycelium（营养菌丝体和气生菌丝体）
Basic unit—— hypha（ pl。 hyphae） This is a tubular cell which is
surrounded by a rigid,chitin-containing cell wall,Hyphae contain nuclei,
mitochondria,ribosomes,Golgi and membrane-bound vesicles within a
plasma-membrane bound cytoplasm
membrane Cell wall
mitochondrion
Vesicals
Dictyosomes
(分散高尔基体 )
Hyphal structures
Specialized morphology of vegetative mycelium
营养菌丝体的特化形态
Rhizoid 假根 —— Rhizopus
Stolon 匍匐菌丝 —— Mucorales,Rhizopus
Haustorium 吸器
Adhesive cell 附着胞
Adhesive branch 附着枝
Sclerotium 菌核
Rhizomorph,funiculus菌索
ring and net 菌环和菌网
1)假根 (rhizoid) 是 Rhizopus(根霉属 )等低等真菌匍匐菌丝与固体基质接触处分化出来的根状结构，具有固着和吸取养料等功能
(2)匍匐菌丝 (stolon)又称匍匐枝。毛霉目 (Mueorales)真菌在固体基质上常形成与表面平行、具有延伸功能的菌丝，称匍匐菌丝。最典型的可在 Rhizopus中见：在固体基质表面的营养菌丝分化为匍匐菌丝，在其上每隔一段距离可长出伸人基质的假根 根霉的形态和构造和伸向空间的孢囊梗，
随着匍匐菌丝的延伸，不断形成新的假根和孢囊梗，这类真菌会随基质的存在而向四处快速蔓延，根本就不会形成像在其他真菌中常见的那样有固定大小和形态的菌落。
sporangium
(3)吸器 (haustorium) 由几类专性寄生的真菌如锈菌目
(Uredinales)、霜霉目 (Peronosporales)和白粉菌目
(Erysiphales)等的一些种所产生。吸器是一种只在宿主细胞间隙间蔓延的营养菌丝上分化出来的短枝，它可侵入细胞内形成指状、球状或丝状的构造，用以吸取宿主细胞内的养料而不使其致死。
(4)附着胞 (adhesive cell) 许多寄生于植物的真菌在其芽管或老菌丝顶端会发产 膨大，分泌粘状物，借以牢固地粘附在宿主的表面，此即附着胞。在其上再形成针状感染菌丝，以侵入宿主的角质表皮而吸取养料。
(5)附着枝 (adhesive branch) 若干寄生真菌由菌丝细胞生出
1— 2个细胞的短枝，将菌丝附着于宿主体上，
（ 6）菌核（ sclerotium) 是一种形状、大小不一的休眠菌丝组织，在不良外界条件下：可保存数年生命力。菌核形状有大有小，大的如茯苓 (大如小孩头 )，
小的如油菜菌核 (形如鼠粪）。菌核的外层色深、坚硬、内层疏松，大多呈白色。
（ 7）菌索（）一般由伞菌等产生，为白色根状菌丝组织，功能为促进菌体蔓延和抵御不良环境。通常可在腐朽的树皮下和地下发现。
(8)菌环 (loop )和菌网 ( net) 捕虫菌目 (zoopasdes)
和一些半知菌的菌丝常会分化成圈环或网状的特化菌丝组织，用以捕捉线虫或其他微小动物，然后进一步从这类环或网上生出菌丝侵入线虫等体内，吸收养料
（ 9）子实体（ fruiting body,sporocarp，
fructification）
Colonial growth
Hyphal tip growth allows fungi to extend into new regions from a
point source or inoculum(接种物 ),Older parts of the hyphae are
often emptied of contents as the cytoplasm is taken forwards with
the growing tip,(老的菌丝通常缺乏内含物，因为细胞质流向生长点 )This creates the radiating colonial pattern seen on agar plates,
in ringworm infections of skin and fairy rings in grass lawns,Only
hyphal tips contribute to extension growth,However older hyphae
can grow aerially or differentiate to produce sporing structures（只有菌丝顶端对延伸生长起作用，而老菌丝可以进行气生生长或分化出产孢子的结构）
Mycelium
in agar
Agar
Surface
mycelium
Kinetics of growth
Fungal growth in a given medium follows the growth phases of
lag,acceleration,exponential,linear,retardation,stationary and
decline（延迟期、加速期、指数期、直线期、减速期、稳定期、衰亡期）,Exponential growth occurs only for a brief period as hyphae
branches initiated,and then the new hypha extends at a linear rate
into uncolonized regions of substrate,
Life cycles All fungi are characterized by
having a period of vegetative growth where their
biomass increases,The length of time and the
amount of biomass needed before sporulation can
occur varies,Almost all fungi reproduce by the
production of spores,but a few have lost all sporing
structures and are referred to as mycelia sterilia(不育菌丝体 ),Different types of spore are produced in
different parts of the life cycle.
Reproduction in fungi
All fungi undergo a period of
vegetative growth where their
mycelium exploits a substrate,
This stage is followed by asexual
and sexual reproduction.
.
There are two conflicting requirements fungi have for their
spores,Spores must allow fungi to spread,but they must also
allow them to survive adverse condi tions,These requirements
are met by different types of spores,Small,light spores are
carried furthest from parent mycelium in air and these are the
dispersal spores（释放型孢子）,They are usually the products of
asexual sporulation,the sporangiospores and the conidiospores,
and so spread genetically identical individuals as widely as
possible,Genetic diversity is maintained by sexual reproduction,
and the spore products are often large resting spores（休眠孢子）
that withstand adverse conditions but remain close to their site of
formation,Spores therefore vary greatly is size,shape and
ornamentation,and this variation reflects specialization of
purpose.
Fungal spores,spores allow
fungi to spread,to maintain
genetic diversity and to survive
adverse conditions
spore discharge,Spores that have a
dispersal function can be released from their parent
mycelium by active or passive mechanisms,As
many spores are wind dispersed,they are produced
in dry friable masses which are passively
discharged by wind,Other spores are passively
discharged by water droplets splashing spores
away from parent mycelium.
Spores may be discharged from
parent mycelium by passive or active
means,Passive mechanisms include
using wind and water as dispersants;
active mechanisms use explosive
principles.
Spores in the atmosphere（ air-borne fungal
spores） can be carried great distances。 Their
presence in the air can have impact on human
health as they can cause allergic rhinitus （ hay
fever） and asthma。 Many plant diseases that
cause great economic losses are air borne。 can
affect human,animal and plant health,They can
cause allergies and spread plant disease.
Air spora
Fungi reproduce by the formation of sexual or asexual
spores
Asexual reproduction
fission
Arthrospore
Budding
blastospore
Other asexual spore
Zoospore
Chlamydospore
Sporangiospore
conidiospora
Sexual reproduction
Oospore
Zygospore
Ascospore
Basidiospore
节孢子 (arthrospore)
某些真菌生长到一定阶段，菌丝中间形成许多隔膜，接着从隔膜处断裂成许多竹节似的无性孢子，称为节孢子，也称为粉孢子。最典型的例于是白地霉
(Geotrichumcandidum
).
arthrospore
Blastospore (芽孢子 )这和酵母菌的出芽一样，它是由母细胞生芽而形成的。当芽长到正常大小时，脱离母细胞，或仍连在母细胞上。
如玉蜀黍黑粉菌
(Ustilago maydis)
能产生芽孢子。某些毛霉或根霉在液体培养基中形成的被称为酵母型细胞，也属芽孢子。
又称厚壁孢子或厚膜孢子。某些真菌生长到 — 定阶段，在菌丝的顶端或中间有部分细胞的细胞质密集在一起，变圆，然后在其四周生出厚壁，或原细胞壁加厚，形成圆形、纺锤形的无性休眠体，来抵抗外界不良的环境条件。例如总状毛霉 (Mucor racemosus)往往在菌丝中间形成许多厚垣孢子
schlamydospore（厚垣孢子）
无性繁殖产生的孢子在孢子囊 (Sporange)内,孢子囊一般生在气生菌丝的顶端或生在孢囊梗 (sporangiophore)的顶端。
在形成孢子囊前，首先有多核的原生质密集于此处，使其膨大，并在下方生出横隔，形成圆形的囊状物，然后其中原生质体割裂成许多小块，每 — 块发育成为 — 个孢子囊孢子。因而每一 ·个孢子囊所含有的孢子的数 — 般都相当多。
就孢子囊孢子而言,— 般有二类,一种具有 — 根或 2~3根鞭毛，能够游动，所以称游动孢子 (zoospore)。例如腐霉
(即 thium)。另一种无鞭毛，不能游动，又称静止担于。
sporangiospore (孢子囊孢子 )
游动孢子
conidium (分生孢子 )
分生孢子的形成方法其形成方式有两种，一种是在分生孢子梗的顶端突出，发育成第一个孢子。梗再伸长形成第二个孢子，如此重复形成一串孢子。这样形成的分生孢子，顶端的最老。曲霉属和青霉届的分生孢子形成，即属于此类型。
另一种是在第 — 个分生孢子形成时，柄的长度已达到最高，由第一个分生孢子顶端生长出第二个分生孢子，如此重复形成一串孢子。
这样形成的分生孢子，下部的最老。如枝孢霉属 (Cladosporium)的分生孢子形成即属于此类型。
Plastic kitchen cutting board surface - rod
bacteria in a smooth matrix; filamentous
bacteria ( 丝状菌 ) -smooth oval cells;
fungal hyphae ( 真菌菌丝 ) with textured
spores ( 结构孢子 ) (x 2,270)
conidium
Zoospore（游动孢子）
Asexual spore,usually
produced by fungi living
in water,Motile
zoospores in motile
sporangia differentiated
from swelled hyphal tips
have a single posterior
flagellum。 The structure
of the flagellum is 9+2,
some has two flagella.
霉菌的有性繁殖是经过不同性别的细胞结合 (质配和核配 )后，产生一定形态的孢子来实现的，这种孢子称为有性孢子。繁殖过程可分为三个阶段：第 — 个阶段为质配；第二个阶段为核配，产生二倍体的核；第三个阶段是减数分裂，恢复核的单倍体状态。大多数真菌菌体是单倍体的。有性孢子通常有下列几种：
Sexual reproduction
菌丝分为雄器
(antheridium)和藏卵器 (oogonium)。藏卵器中有一个或数个卵球
(oosphere)。当雄器和藏卵器相配时，雄器中细胞质与细胞核，通过受精管而进入藏卵器，
与卵球结合形成卵孢子。
图所示是德巴利腐霉的卵孢子的形成。
oospore (卵孢子 )
（ b）同宗结合（ a）异宗结合根霉的接合孢子
Zygospore（接合孢子）
ascospore （子囊孢子）
形成子囊孢子是子囊菌的主要特征。子囊中孢子数目通常为 1~8个，或为 2n。典型的子囊中有 8个孢子。大多数霉菌的子囊是包裹在子囊果（ ascocarp）中。
子囊果有三种类型 子囊壳 perithecium 子囊盘 apothecium
闭囊壳 cleistothecium
Sexual reproduction in this group occurs after somatic fusion of
different mating-type mycelia,A transient diploid phase is rapidly
followed by the formation of ascospores within sac-shaped asci
differentiated from modified hyphal tips,In the initial stages of ascal
development hooked hyphal tips form,called croziers （产囊丝钩）
or shepherds‘ crooks（牧羊杖） because of their shape,They have
distinctive septae at their base which insure that two different
mating-type nuclei are main tained in the terminal cell,Formation of
the septae is coordinated with nuclear division,In yeasts all these
events occur within one cell,after fusion of two mating-type cells,
the whole cell being converted into an ascus.
The formation of ascospores
Sexual reproduction in the ascomycetes
In more complex Ascomycetes many asci form together,creating a
fertile tissue called a hymenium（叫子实层的能育组织）,In some
groups the hymeniumcan be supported or even enclosed by large
amounts of vegetative mycelium,The whole structure is called a
fruit body or sporocarp（子囊果） and is used as a major taxonomic
feature,They can become large enough to be seen with the naked
eye,Flask-shaped sexual reproductive bodies are called perithecia,
cup-shaped bodies are called apothecia and closed bodies are
called cleistothecia,These structures have evolved to protect the
asci in spore dispersal,but the hymenium itself is unafected by the
presence of water。
The formation of sporocarp
and its forms
Cup-shaped
apothecium
Flask-shaped
perithecium
Closed
cleistothecium
Asci
Asci
Ascus
containing
ascospores
Basidiomycete fungi rarely reproduce asexually,Sexual reproduction
is by the formation of basidiospores on the gills or pores of large fruit
bodies.This group of fungi are characterized by the most complex
and large structures found in the fungi,They are also distinctive in
that they very rarely produce asexual spores,Much of the life cycle is
spent as vegetative mycelium,exploiting complex substrates,A
preliminary requisite for the onset of sexual reproduction is the
acquisition of two mating types of nuclei by the fusion of compatible
hyphae,Single representatives of the two mating-type nuclei are held
within every hyphal compartment for extended periods of time,This is
termed a dikaryotic state（双核期）,and its maintenance requires
elaborate septum formation during growth and nuclear division,
Basidiospore
Onset of sexual-spore formation is triggered by
environmental conditions and begins with the formation of a
fruit body primordium（子实体原基）,Dikaryotic mycelium
（双核菌丝体） expands and differentiates to form the large
fruit bodies we recognize as mushrooms and toadstools（毒蕈）,Diploid formation and meiosis occur within a modified
hyphal tip called a basidium 。
Basidium formation
核融合
Nuclear fusion 减数分裂meiosis
担孢子梗
sterigmata
Basidio
spores
担孢子
Basidium
（担子）
Basidium and basidiospore
formation
Four spores are budded from the basidium,Basidia form
together to create a hymenium which is highly sensitive
to the presence of free water,The hym-enium is
distributed over sterile,dikaryotic supporting tissues
which protect it from rain,The hymenium can be exposed
on gills or pores beneath the fruit body,seen in the
toadstools and bracket fungi,or enclosed within
chambers as in the puffballs and truffles
Formation of
basidiospore
puffball （马勃）
Bracket
（檐状伞）
Toadstool
（毒蘑菇） Hymenenium
（子实层）
Structure of sexual sporocarps in the basidiomycetes
basidiospore（担孢子）
担孢子是担子菌特有的特征。它是一种外生孢子，
经过两性细胞核配合后产生。因为它生在担子上，
所以称为担孢子。典型的担子菌的担子上有四个担孢子。
各种担孢子的形状及表面特征
Food related molds
1,Aspergillus 曲霉属
2,penicillium（青霉属 ）
3,Rhizopus （根霉属）
4,sporotrichum (侧孢霉属 )
5,Thamnidium(枝霉属 )
6,Alternaria（交链孢属）
7.Botrytis （葡萄孢霉）
8.Trichoderma（木霉属）
9.Monascus（红曲属）
10.Gibberella（赤霉属）
11.Cordyceps（虫草属）
12.geotrichum（地霉属）
13.helminthosporium（长蠕孢霉）
food related Moulds Aspergillus曲霉属分生孢子初生小梗孢子穗 小梗次生小梗顶囊足细胞
Conidia
primary sterigma
conidial head sterigme
secondary sterigma
Vesicle
foot cell
Morphology of Conidial head is the basis for species identification
孢子穗的形态是菌种鉴定的依据
Aspergillus
Relationship with food—— beneficial
Fermentation industry
soy sauce酿酱
vinegar制醋曲
fermented bean curd腐乳
alcohol beverage酿酒
Food processing
organic acid有机酸
enzyme 酶制剂淀粉酶蛋白酶果胶酶等
Relationship with food—— harmful
Usually distributed on the surface of following foodstuff：
Cakes,fruits,vegetables,meat,grain and other
organic objects。
Causing following consequences：
Go mouldy； become mildewed
Produce or secrete carcinogenic
substance（ blastomogen）致癌物质
eg 。 aflatoxin（黄曲霉毒素）
Food related molds—— penicillium（青霉属 ）
十分接近于曲霉，在自然界分布很广，长生长在腐烂的柑橘皮上，呈青绿色，不少种类引起食品变质，但也用来生产青霉素和有机酸等。
青霉菌菌丝与曲霉相似，但无足细胞，孢子穗结构也不同。
其分生孢子梗顶端不膨大，而是经过多次分枝产生几轮对称或不对称的小梗，然后在小梗的顶端产生成串的分生孢子。青霉菌的孢子穗形状似扫帚状。分生孢子球形、椭圆形或短柱形，
一般呈蓝绿色。
Plastic kitchen cutting board surface - rod bacteria in a
smooth matrix; filamentous bacteria ( 丝状菌 ) -smooth oval
cells; fungal hyphae ( 真菌菌丝 ) with textured spores ( 结构孢子 ) (x 2,270)
根霉在自然界分布广泛，经常出现在淀粉质食品上，引起粮食、
食品腐烂、腐败。 I工业上常利用根霉生产糖化酶，甜酒曲中主要菌种也是根霉。此外，根霉也可以用来生产有机酸等其它物质。
Food related molds—— Rhizopus （根霉属）
Rhizoid
假根
Stolen
匍匐丝
sporange
Uaually black
sporangiophore
菌丝分隔 ·分生孢子梗分枝，顶端产生分生孢子。分生孢子单细胞，梨形。菌落呈奶油色泽，时间长后，为干燥粉末状。
已经报告该菌能在 O~C以下生长，常在冷藏肉中形成白色斑点。
food related molds— sporotrichum (侧孢霉属 )
S,Carnis
肉色侧孢霉
Conidium
分生孢子
Conidiophore
分生孢子梗
Cause the deterioration of
vegetables and fruit
conidium
conidiophore
形状大小不定，数个连接成链，暗褐色，有纵横隔膜，
呈壁砖状 。
大多数不分支，较短，单生或成簇，
暗褐色。
Food related molds—— Alternaria（交链孢属）
septate mycelium
Food related molds—— Botrytis （葡萄孢霉）
conidiophore
conidium
分生孢子梗顶端形成树枝状分支，分支顶端细胞常常膨大，
在短的小梗上着生分生孢子，
如一串葡萄。
卵圆形，无色或暗褐色。
常产生外形不规则的黑色菌核（ sclerotium）。
分布在许多植物和植物食品上，形成一层“灰色霉”，
引起水果、蔬菜的腐败。
Food related molds—— Trichoderma（木霉属）
Spherical or elliptical
（ oval）,smmoth or
rough,yellow-green
conidia
Colorless hypha,with septa and branches,
produce chlamydospores
Bottle-like
sterigme
瓶状小梗
Spore head gathered
（ conglutenated） by mucus
（ slime）
Food related molds—— Trichoderma（木霉属）
Colony grows rapidly,like cotton fibre（棉絮状），
white at first,later become green。 Spore-producing
area takes on（ has） concentric circles
Sone species has cellulolytic activity,therefore can
be used to produce cellulase to manufacture sugars
with cellular waste（下脚）,starch processing and
food processing
Moldy grain,fruit and
vegetables
Mildew and rot of cellular
material。
Food related molds—— Monascus（红曲属）
Can secrete red pigment
The source of natural red pigment in the food
processing,for instance red rice（ ang-kak）
used in the processing of red fermented bean
curd,bevarage and meat is prepared from
Monascus。
Type culture that commonly
used,M,purpureus（紫红曲）
Food related molds—— Monascus（红曲属）
Colony features,membranous colony covers
the whole malt extract plate,mycelium is
white at first,later becomes red,red-purple，
the water-soluble pigments are secreted into
the medium。
conidium
Food related molds—— Monascus（红曲属）
1~3 initiate
cleistothecium
4~5 premature
cleistothecium
6 mature
cleistothecium
cleistothecium of M.purpureus
紫红曲的闭囊壳
Food related molds—— Gibberella（赤霉属）
reproduction
scarcely produce Sexual generatin （ gamobium,sexual
progeny）,sexual spore is ascospore in spherical,smooth
and blue perithecium（子囊壳）。
Asexual reproduction produce two types of conidium
Small type,single
cellular,spherical，
elliptical to long
column,colorless or
other colors
Large type：
multicellular
with septa，
Sickle-like or
long column，
Colorless or
other colors
Food related molds—— Gibberella（赤霉属）
Gibberellin or abbeymycin （赤霉素）
Metabolic product of Gibberella,is a kind of hormone
with the following function：
1.Stimulate plant growth
2.Break the dormancy of seed and tuber
3.Increase the yield of vegetables especially leafy
vegetables
Food related molds—— Cordyceps（虫草属）
Formation,The insect body parasitized by the fungi was full of
mycelium（ sclerotium 菌核） and mummified,stem-head like or
rod like stroma （ plural stromata 子座） grows out from its front
end。
Inchworm
尺蠖
Stroma （ grass）
usually single，
scarcely 2 or 3，
4~11cm in length。
perithecium
Ascus
（ asci）
ascospore
Cordyceps sinesis冬虫夏草
Food related molds—— geotrichum（地霉属）
Reproduction by fission,septate hypha,hypha may break
into arthrospore,without blastospore。
Always existed in sauerkraut（ kimchi,pickles泡菜），
fecund,organic fertilizer,rotten fruit and vegetables and
other plant residues。
Arthrospore
germination
Hypha breaks into
fragment----arthrospore
G,Candidum (白地霉 )
Food related molds—— helminthosporium（ 长蠕孢霉 ）
conidiophore
conidium
Colorless or gray septate mycelium,septate
conidiophore,conidium is black-gray,usually has
4~6 cells,many fungi of the genera are both
parasite and saprobe （ saprophytic bacterium，
saprogen,saprotroph，腐生菌）
Food related molds—— geotrichum（地霉属）
Some species has high nutritional value,has
the following usages:
1,Edible or as forage supplement
2,Nucleic acid extraction
3,Fat synthesis
G.candidum
Eukaryote—— yeast
Definition,yeast is a group of
unicelled eukaryotic microorganisms
reproduced by budding,Generally it
refers to all single-celled eukaryotes
that can ferment carbohydrates.
Eukaryote—— yeast
It‘s a kind of microbes utilized early by human
being,Mainly exists in the acidic environment
with high sugar content such as on the fruits，
vegetables,flower honey and confect,or in
the orchard soil,Most yeasts are saprophyte and
beneficial to human being,only a few are
parasitism and can cause the human being，
plant and animal diseases,Some yeasts can lead
to the deterioration of fruit juice,jam,honey，
alcohol beverage,and meat.
Yeast cell morphology and structure
Most yeast are unicell usually are spherical,oval
or column shape,some species may form lotus
root shaped pseudomycelium,
Diagram of yeast cell structure
Saccharomyces
cerevisiae is the
most typical and
the most important
yeast,The figure
right shows its cell
structure.
membrane
vacuole
Cell wallmitochondrion
Nucleus
Endoplasmic
reticulum
The major components of yeast cell wall are glucan（葡聚糖） and
mannan（甘露聚糖）,and different amount of proteins,lipids
and chitin （几丁质）,Infant cells has homologous cytoplasm，
later vacuole emerged,
Yeast structures
Colonial morphology
Like bacterial colonies,yeast colony has following features：
wettish （ humid）,a little transparent,with lubricous （光滑的
slippery） surface and even texture and can be easily picked up，
the obverse side and the reverso side,the edge and the center
has the same color,Other hand,it is bigger,thicker,denser，
and a little opaque than that of bacterium,Compared with
bacteria,its colony only has several colors,normally is milk
white or candle white（矿烛色）,few are red,one or two is
black,Those without pseudomycelium has bulged colony with
round edge,while Candida has the flat colony with coarse
brink and surface.
Reproduction of yeast
Budding,by all yeasts
Asexual fission,by schizosaccharomycetes
arthrospore
Asexual sporulation ballistospore
chlamydospore
Sexual,by formation of ascus and ascospore
Budding
When yeast grows on a plate of rich nutrition and under optimal
culture condition,it multiply rapidly,nearly all cells are
budding,therefore,conglomerated into cell clusters（ balls）,
After a series of budding,if daughter yeasts don‘t depart from
parent cells,and only linked by narrow and small area,thus
formed lotus root shaped cell strings called pseudohyphae.
Pseudohyphae and euhyphae
Otherwise,cells linked and the septa area is the same as cell
diameter formed laemodipodiform（竹节形） cell strings,that
is called euhyphae euhyphae 。
When daughter yeast depart from the parent cell,Scar was
leaved on both of them,called bud scar（ on parent cell） and
birth scar（ on daughter cell） respectively.
Bud scar and birth scar
光学显微镜下看到的酵母细胞这里显示的菌种 是用来发面团以及将葡萄汁转变成酒的那些细胞。他们繁殖时先出芽，进而不对称分裂为一大一小两个子细胞酿酒酵母
（ saccharomyces cerevisiae）
Food related yeasts(1)——
saccharomyces （ 酵母属 ）
Saccharomyces widely colonized on fruits and
vegetables,orchard and seed yeast （酒曲）,
Spherical,elliptical,sausage-shaped reproduced by
multi-ends budding or sexually producing 1~4
ascospores,Strong fermentative ability,major
products are ethonal and co2,Can‘t use lactose and
high-level hydrocarbon（烃类 ).
features
Many species are widely used in industry,for
instance S,cerevisiae（酿酒酵母） can be used in
brewing of beer,alcohol and other beverages，
as well as bread making.
Beneficial
Some cause the fruit and vegetable fermentation，
therefore cause food decay,For example S.rouxii （鲁氏毛霉） and S,Melliscan（蜂蜜酵母） are tolerant to
sugar solution of high concentration cause the
spoilage or deterioration of jam and other foods,They
can also survive in high concentrative salt solution，
live in soy sauce and form a layer of gray-white，
powder-like pellicle,thus affect the quality of soy
sauce.
Detrimental
酿酒酵母的光镜照片
Saccharomyces cerevisiae 酿酒酵母 SEM
10μm
Food related yeasts
（ 2） Brettanomyces （酒香酵母属）
Some species involved in the post-fermentative period in the
brewing of some Europe beers.
Some other species can be isolated from deteriorated Kraut,
fruits and vegetables.
（ 3） Candida （假丝酵母属）
Normally exists on the surface of fresh and salted meat
and other many foods.
Food related yeasts
(4)Debaromyces （德巴利酵母属 ）
Usually can be isolated from the flowing deteriorated food：
meat,sausage and alcohol beverages.
(5)Endomycopsis（拟内酵母属 ）
Form euhyphae and usually form a thin layer of pellicle,can be
detected from flowing foods,grains,fermented sauerkraut or
cucumber and Some species can be used to produce αandβ amylase.
(6)Hansenula （汉逊酵母属）
Usually formed pseudohyphae,grows on oranges,grape
and the their product or condensed juice.
Food related yeasts
(7) Kloeckera （克勒克酵母属）
This group can both involve in the fermentation and oxidation,
usually grows on fruit the contaminated by the fruit flies,Some
species can leads to the abnormal smell or turbidity of alcoholic
beverages,
(8)Mycoderma（醭酵母属）
Form a thick layer of mycoderm（ pellicle） floated above the
beer,vinegar,sauerkraut,fruit juice and their product.
Food related yeasts
(10)Rhodotorula（红酵母属）
Widely existed in the environment,many can produce red
pigment on food or medium,Some species can cause human
and animal diseases.
(9)Pichia （毕赤氏酵母属）
Contaminative fungi of alcohol industry,always form a
layer of white,dry pellicle,Many species can form
pseudohyphae and produce ascospore,has weak ability of
catalyzing (assimilating) carbohydrates,don’t produce
ethonal.
