Lecture 6
? 6.8 Effect of Environment on Growth
? 6.9 Microbial Growth at Cold
Temperatures
? 6.10 Microbial Growth at High
Temperatures
? 6.11 Microbial Growth at Low or High pH
? 6.12 Osmotic Effects on Microbial Growth
? 6.13 Oxygen and Microbial Growth
Effect of Temperature on Growth Rate
Variations in Temperature Optima
Psychrophiles
? Optimum 15° C or lower
? Maximum <20°
? Minimum ?0°
? Many are very sensitive to moderate
temperatures
? Enzyme denaturation at moderate temp
? Greater proportion of unsaturated fatty acids
in membrane phospholipids
? Ocean depths,constant temp <5oC
Psychrotolerant
? Grow at 0°
? Optimum 20-40°
? Mesophiles capable of growth at low
temperatures
? found in temperate climates
Core sample of McMurdo Sound sea ice
Table 6,1 Upper tem perature lim its f or growth
G r ou p Upp e r t e m p lim it
( ° C)
A n im a ls
F ish 38
In se c ts 45 - 50
Cru sta c e a n s 49 - 50
Pl a n ts
V a sc u la r P la n ts 45
M o ss e s 50
Eu k a r y o tic M ic r o o r g a n ism s
P ro to z o a 56
A lg a e 55 - 60
F u n g i 60 - 62
Pr o k a r y o te s
Ba c te r ia
Cy a n o b a c te ria 70 - 74
A n o x y g e n ic
p h o to tro p h s
70 - 73
Ch e m o tro p h s 95
A rc h a e a 113
Figure 6.20 Yellowstone National Park
Examples of Hot Environments
? soil surface in midsummer sun,50oC
? compost piles,65oC
? hot springs,boiling point of water
? ocean floor hydrothermal vents,350oC
? hot water heaters
Salt Tolerance
Tabl e 5.2 Wat er A cti vit y
Wate r a cti vit y,a
w
Mat erial Examples of or ganis ms
1,000 Pure W at er Caulobac te r,Spi rill um
0,995 Hum an Blood Strept ococcus,E sche richi a
0,980 Seawa te r Pseudomonas,V ibrio
0,950 Brea d Mos t gra m - positi ve rods
0,900 Maple s y rup,ha m Staphy loccus
0,850 Sala m i Sacc harom yc es rouxii
0,800 Fruit c ake,j ams Sacc harom yc es bail ii,Penicilliu m
0,750 Salt l ake s,sal te d fish Halobact erium,Halococ cus
0,700 Cere a ls,ca nd y,drie d fru it Xe rom yc es b isporus
Compatible Solutes
Ta ble 6.4 Ox y g e n r e la tionshi ps of micr oor g a nisms
G r o u p R e la tio n sh ip
to O
2
Ty p e o f
m e ta b o li sm
Ex a m p le H a b ita t
A e r o b e s
O b l i g a t e R e q u i r e d A e r o b i c
r e sp i r a t i o n
Mi c ro c o c c u s l u t e u s S k i n,d u st
F a c u l t a t i v e N o t r e q u i r e d,b u t
g r o w t h b e t t e r
w i t h O
2
A e r o b i c,
an a e r o b i c
r e sp i r a t i o n,
f e r me n t a t i o n
Esch e ri c h i a c o l i M a mm a l i a n
l a r g e i n t e st i n e
M i c r o a e r o p h i l i c R e q u i r e d b u t a t
l e v e l s l o w e r t h a n
a t mo sp h e r i c
A e r o b i c
r e sp i r a t i o n
S p i ri l l u m v o l u t a n s L a k e w a t e r
A n a e r o b e s
A e r o t o l e r a n t N o t r e q u i r e d,
a n d g r o w t h n o
b e t t e r w h e n O
2
p r e se n t
F e r me n t a t i o n S t rep t o c o c c u s
p y o g e n e s
U p p e r
r e sp i r a t o r y t r a c t
O b l i g a t e H a r mf u l o r
l e t h a l
F e r me n t a t i o n
o r a n a e r o b i c
r e sp i r a t i o n
Me t h a n o b a c t e ri u m
f o rm i c i c u m
S e w a g e sl u d g e
d i g e st o r s,
a n o x i c l a k e
se d i me n t s
Figure 6.25
Thioglycolate Broth
Thioglycolate is a
good reducing
agent
Resazurin is
a redox
indicator
dye
Figure 6.25
Thioglycolate Broth
Thioglycolate is a
good reducing
agent
Resazurin is
a redox
indicator
dye
aerobic anaerobic facultative microaerophilic aerotolerant
Toxic forms of oxygen
Enzymes that destroy toxic oxygen
testing for the presence of catalase
H2O2 + H2O2 ? 2 H2O + O2
? 6.8 Effect of Environment on Growth
? 6.9 Microbial Growth at Cold
Temperatures
? 6.10 Microbial Growth at High
Temperatures
? 6.11 Microbial Growth at Low or High pH
? 6.12 Osmotic Effects on Microbial Growth
? 6.13 Oxygen and Microbial Growth
Effect of Temperature on Growth Rate
Variations in Temperature Optima
Psychrophiles
? Optimum 15° C or lower
? Maximum <20°
? Minimum ?0°
? Many are very sensitive to moderate
temperatures
? Enzyme denaturation at moderate temp
? Greater proportion of unsaturated fatty acids
in membrane phospholipids
? Ocean depths,constant temp <5oC
Psychrotolerant
? Grow at 0°
? Optimum 20-40°
? Mesophiles capable of growth at low
temperatures
? found in temperate climates
Core sample of McMurdo Sound sea ice
Table 6,1 Upper tem perature lim its f or growth
G r ou p Upp e r t e m p lim it
( ° C)
A n im a ls
F ish 38
In se c ts 45 - 50
Cru sta c e a n s 49 - 50
Pl a n ts
V a sc u la r P la n ts 45
M o ss e s 50
Eu k a r y o tic M ic r o o r g a n ism s
P ro to z o a 56
A lg a e 55 - 60
F u n g i 60 - 62
Pr o k a r y o te s
Ba c te r ia
Cy a n o b a c te ria 70 - 74
A n o x y g e n ic
p h o to tro p h s
70 - 73
Ch e m o tro p h s 95
A rc h a e a 113
Figure 6.20 Yellowstone National Park
Examples of Hot Environments
? soil surface in midsummer sun,50oC
? compost piles,65oC
? hot springs,boiling point of water
? ocean floor hydrothermal vents,350oC
? hot water heaters
Salt Tolerance
Tabl e 5.2 Wat er A cti vit y
Wate r a cti vit y,a
w
Mat erial Examples of or ganis ms
1,000 Pure W at er Caulobac te r,Spi rill um
0,995 Hum an Blood Strept ococcus,E sche richi a
0,980 Seawa te r Pseudomonas,V ibrio
0,950 Brea d Mos t gra m - positi ve rods
0,900 Maple s y rup,ha m Staphy loccus
0,850 Sala m i Sacc harom yc es rouxii
0,800 Fruit c ake,j ams Sacc harom yc es bail ii,Penicilliu m
0,750 Salt l ake s,sal te d fish Halobact erium,Halococ cus
0,700 Cere a ls,ca nd y,drie d fru it Xe rom yc es b isporus
Compatible Solutes
Ta ble 6.4 Ox y g e n r e la tionshi ps of micr oor g a nisms
G r o u p R e la tio n sh ip
to O
2
Ty p e o f
m e ta b o li sm
Ex a m p le H a b ita t
A e r o b e s
O b l i g a t e R e q u i r e d A e r o b i c
r e sp i r a t i o n
Mi c ro c o c c u s l u t e u s S k i n,d u st
F a c u l t a t i v e N o t r e q u i r e d,b u t
g r o w t h b e t t e r
w i t h O
2
A e r o b i c,
an a e r o b i c
r e sp i r a t i o n,
f e r me n t a t i o n
Esch e ri c h i a c o l i M a mm a l i a n
l a r g e i n t e st i n e
M i c r o a e r o p h i l i c R e q u i r e d b u t a t
l e v e l s l o w e r t h a n
a t mo sp h e r i c
A e r o b i c
r e sp i r a t i o n
S p i ri l l u m v o l u t a n s L a k e w a t e r
A n a e r o b e s
A e r o t o l e r a n t N o t r e q u i r e d,
a n d g r o w t h n o
b e t t e r w h e n O
2
p r e se n t
F e r me n t a t i o n S t rep t o c o c c u s
p y o g e n e s
U p p e r
r e sp i r a t o r y t r a c t
O b l i g a t e H a r mf u l o r
l e t h a l
F e r me n t a t i o n
o r a n a e r o b i c
r e sp i r a t i o n
Me t h a n o b a c t e ri u m
f o rm i c i c u m
S e w a g e sl u d g e
d i g e st o r s,
a n o x i c l a k e
se d i me n t s
Figure 6.25
Thioglycolate Broth
Thioglycolate is a
good reducing
agent
Resazurin is
a redox
indicator
dye
Figure 6.25
Thioglycolate Broth
Thioglycolate is a
good reducing
agent
Resazurin is
a redox
indicator
dye
aerobic anaerobic facultative microaerophilic aerotolerant
Toxic forms of oxygen
Enzymes that destroy toxic oxygen
testing for the presence of catalase
H2O2 + H2O2 ? 2 H2O + O2
