Bacteria : The Proteobacteria

Copyright © 2009 Pearson Education Inc., publishing as Pearson Benjamin Cummings

Bacteria: The Proteobacteria

Chapter 17


The Phylogeny of Bacteria

I. Phylum Proteobacteria


The Phylogeny of Bacteria – Major phyla of domain Bacteria

Phy

loge

netic

Ove

rvie

w o

f Bac

teria


Phy

lum

Pro

teob

acte

ria

A m

ajor

line

age

(phy

la)

of B

acte

ria

In

clud

es m

any

of t

he m

ost

com

mon

ly e

ncou

nter

ed b

acte

ria

M

ost

met

abol

ical

ly d

iver

se o

f al

l dom

ain

Bac

teria

E

.g.,

chem

olith

otro

phy,

che

moo

rgan

otro

phy,

pho

totr

ophy

M

orph

olog

ical

ly d

iver

se

D

ivid

ed in

to f

ive

clas

ses

A

lpha

-, B

eta-

, Del

ta-,

Gam

ma-

, Eps

ilon-


Major Genera of Proteobacteria


1. P

urpl

e P

hoto

trop

hic

Bac

teria

2. T

he N

itrify

ing

Bac

teria

3. S

ulfu

r- a

nd Ir

on-O

xidi

zing

Bac

teria

4. H

ydro

gen-

Oxi

dizi

ng B

acte

ria

5. M

etha

notr

ophs

and

Met

hylo

trop

hs

II Phototrophic, Chemolithotrophic & Methanotrophic Proteobacteria


1. Purple Phototrophic Bacteria

P

urpl

e P

hoto

trop

hic

Bac

teria

C

arr

y o

ut a

no

xyg

en

ic p

ho

tosy

nth

esi

s; n

o O

2 e

volv

ed

M

orp

ho

log

ica

lly d

ive

rse

gro

up

G

en

era

fall

with

in th

e A

lph

a-,

Be

ta-,

or

Ga

mm

ap

rote

ob

act

eria

C

on

tain

ba

cte

rioch

loro

ph

ylls

an

d c

aro

ten

oid

pig

me

nts

P

rod

uce

intr

acy

top

lasm

ic p

ho

tosy

nth

etic

me

mb

ran

es

with

va

ryin

g m

orp

ho

log

ies


Liquid Cultures of Phototrophic Purple Bacteria

Figure 15.2


Membrane Systems of Phototrophic Purple Bacteria

Figure 15.3


Purple Phototrophic Bacteria

P

urpl

e S

ulfu

r B

acte

ria

U

se h

ydro

ge

n s

ulfi

de

(H

2S)

as

an

ele

ctro

n d

on

or

for

CO

2 re

du

ctio

n in

ph

oto

syn

the

sis

S

ulfi

de

oxi

diz

ed

to e

lem

en

tal s

ulfu

r (S

o ) th

at i

s st

ore

d

as

glo

bu

les

eith

er

insi

de

or

ou

tsid

e c

ells

S

ulfu

r la

ter

disa

ppea

rs a

s it

is o

xidi

zed

to s

ulfa

te (

SO

42

- )


Photomicrographs of Purple Sulfur Bacteria

Figure 15.4


Purple Phototrophic Bacteria

P

urpl

e S

ulfu

r B

acte

ria (

cont

’d)

M

an

y ca

n a

lso

use

oth

er

red

uce

d s

ulfu

r co

mp

ou

nd

s,

such

as

thio

sulfa

te (

S2O

32-)

A

ll a

re G

am

ma

pro

teo

ba

cte

ria

F

ou

nd

in il

lum

ina

ted

an

oxi

c zo

ne

s o

f la

kes

an

d o

the

r

aq

ua

tic h

ab

itats

wh

ere

H2S

acc

um

ula

tes,

as

we

ll a

s

sulfu

r sp

ring

s


Genera and Characteristics of Purple Sulfur Bacteria






Blooms of Purple Sulfur Bacteria

Figure 15.5


Purple Non-sulfur Bacteria

P

urpl

e N

onsu

lfur

Bac

teria

O

rigin

ally

tho

ught

org

anis

ms

wer

e un

able

to

use

sulfi

de a

s

an e

lect

ron

dono

r fo

r C

O2 r

educ

tion,

now

kno

w m

ost

can

M

ost

can

grow

aer

obic

ally

in t

he d

ark

as

chem

oorg

anot

roph

s

S

ome

can

also

gro

w a

naer

obic

ally

in t

he d

ark

usin

g

ferm

enta

tive

or a

naer

obic

res

pira

tion

M

ost

can

grow

pho

tohe

tero

trop

hica

lly u

sing

ligh

t as

an

ener

gy s

ourc

e an

d or

gani

c co

mpo

unds

as

a ca

rbon

sou

rce

A

ll in

Alp

ha-

and

Bet

apro

teob

acte

ria


Representatives of Purple Nonsulfur Bacteria

Figure 15.6


Genera and Characteristics of Purple Nonsulfur Bacteria


Genera and Characteristics of Purple Nonsulfur Bacteria


2. The Nitrifying Bacteria

N

itrify

ing

Bac

teria

A

ble

to g

row

che

mol

ithot

roph

ical

ly a

t th

e ex

pens

e of

redu

ced

inor

gani

c ni

trog

en c

ompo

unds

F

ound

in A

lpha

-, B

eta-

, G

amm

a-,

and

Del

tapr

oteo

bact

eria

N

itrifi

catio

n (o

xida

tion

of a

mm

onia

to

nitr

ate)

occ

urs

as t

wo

sepa

rate

rea

ctio

ns b

y di

ffer

ent

grou

ps o

f ba

cter

ia

A

mm

onia

oxi

dize

rs (

nitr

osify

ers)

(e.

g., N

itros

ococ

cus)

N

itrite

oxi

dize

r (n

itrify

er)

(e.g

., N

itrob

acte

r)

Many species have internal membrane systems that house key

enzymes in nitrification

Ammonia monooxygenase: oxidizes NH3 to NH2OH

Nitrite oxidase: oxidizes NO2- to NO3

-


N

itrify

ing

Bac

teria

(co

nt’d

)

W

ide

spre

ad

in s

oil

an

d w

ate

r

H

igh

est

nu

mb

ers

in h

ab

itats

with

larg

e a

mo

un

ts o

f

am

mo

nia

i.e

., si

tes

with

ext

ensi

ve p

rote

in d

ecom

posi

tion

and

sew

age

trea

tmen

t fac

ilitie

s

M

ost

are

ob

liga

te c

he

mo

lith

otr

op

hs

an

d a

ero

be

s

O

ne e

xcep

tion

is a

nnam

ox o

rgan

ism

s, w

hich

oxi

dize

am

mon

ia

anae

robi

cally


Figure 15.7


http://californiaagriculture.ucanr.edu/landingpage.cfm?article=ca.v063n02p67&fulltext=yes

As carbon dioxide rises, food quality will decline without careful nitrogen management

Copyright © 2009 Pearson Education Inc., publishing as Pearson Benjamin Cummingshttp://hoorayfordecaycomposting.com/2013/01/28/the-nitrogen-cycle/


3. Sulfur- and Iron-Oxidizing Bacteria

S

ulfu

r-O

xidi

zing

Bac

teria

G

row

ch

em

olit

ho

tro

ph

ica

lly o

n r

ed

uce

d s

ulfu

r cm

pd

s

Tw

o b

roa

d c

lass

es

N

eutr

ophi

les

A

cido

phile

s (s

ome

also

use

fer

rous

iron

(F

e2+)

Thiobacillus (rods) Sulfur compounds most commonly used as electron

donors are H2S, So, S2O32-; generates sulfuric acid

Achromatium (spherical cells)

Common in freshwater sediments

Some obligate chemolithotrophs possess special structures that house Calvin cycle enyzmes (carboxysomes)


B

eggi

atoa

F

ilam

ento

us,

glid

ing

bact

eria

F

ound

in h

abita

ts r

ich

in H

2S

e

.g.,

sulfu

r sp

rings

, dec

ayin

g se

awee

d be

ds, m

ud la

yers

of

lake

s, s

ewag

e po

llute

d w

ater

s, a

nd h

ydro

ther

mal

ven

ts

Mos

t gr

ow m

ixot

roph

ical

ly

with

red

uced

sul

fur

com

poun

ds a

s el

ectr

on d

onor

s

and

org

anic

com

poun

ds a

s ca

rbon

sou

rces

Thioploca Large, filamentous sulfur-oxidizing bacteria that form cell

bundles surrounded by a common sheath

Thick mats found on ocean floor off Chile and Peru

Couple anoxic oxidation of H2S with reduction of NO3- to NH4

+


Non-filamentous Sulfur Chemolithotrophs Figure 15.9Filamentous Sulfur-Oxidizing Bacteria


Sulfur- and Iron-Oxidizing Bacteria

S

ulfu

r-O

xidi

zing

Bac

teria

(co

nt’d

)

T

hiot

hrix

F

ilam

ento

us s

ulfu

r-ox

idiz

ing

bact

eria

in w

hich

fila

men

ts

grou

p to

geth

er a

t th

eir

ends

by

a ho

ldfa

st t

o fo

rm

cellu

lar

arra

ngem

ents

cal

led

rose

ttes

O

blig

ate

aero

bic

mix

otro

phs


Thiothrix

Figure 15.12


4. Hydrogen-Oxidizing Bacteria

H

ydro

gen-

Oxi

dizi

ng B

acte

ria:

M

ost

ca

n g

row

au

totr

op

hic

ally

with

H2

as

sole

ele

ctro

n

do

no

r a

nd

O2

as

ele

ctro

n a

cce

pto

r (“

kna

llga

s” r

ea

ctio

n)

B

oth

gra

m-n

eg

ativ

e a

nd

gra

m-p

osi

tive

re

pre

sen

tativ

es

kno

wn

C

on

tain

on

e o

r m

ore

hyd

rog

en

ase

en

zym

es

tha

t fu

nct

ion

to b

ind

H2

an

d u

se it

to e

ithe

r p

rod

uce

AT

P o

r fo

r re

du

cin

g p

ow

er

for

au

totr

op

hic

gro

wth

Most are facultative chemolithotrophs and can grow chemoorganotrophically

Some can grow on carbon monoxide (CO) as electron

donor (carboxydotrophs)


Hydrogen Bacteria

Figure 15.13


Characteristics of Common Hydrogen-Oxidizing Bacteria


5. Methanotrophs and Methylotrophs

M

etha

notr

ophs

U

se C

H4a

nd

a fe

w o

the

r o

ne

-ca

rbo

n (

C1

) co

mp

ou

nd

s

as

ele

ctro

n d

on

ors

an

d s

ou

rce

of c

arb

on

W

ide

spre

ad

in s

oil

an

d w

ate

r

O

blig

ate

ae

rob

es

M

orp

ho

log

ica

lly d

ive

rse

Methylotrophs Organisms that can grow using carbon compounds

that lack C-C bonds [(CH3)2N (trimethylamine)HCOO-

(formate), CH3OCOO CH3 (Dimethyl carbonate), (CH3)2SO (dimethyl sulfoxide), CH3OH (methanol), CH3NH2 (methylamine), CH3)2NH (dimethylamine)]

Most are also methanotrophs – use CH4



Met

hano

trop

hs (

cont

'd)

M

eth

an

otr

op

hs

me

tha

ne

mo

no

oxy

ge

na

se

W

hich

inco

rpor

ates

an

atom

of

oxyg

en f

rom

O2 in

to m

etha

ne

to p

rodu

ce m

etha

nol

M

eth

an

otr

op

hs

con

tain

larg

e a

mo

un

ts o

f ste

rols

Classification of Methanotrophs Two major groups:

Type I

Type II

Contain extensive internal membrane systems for methane oxidation



Typ

e I M

etha

notr

ophs

Ass

imila

te C

1 c

om

po

un

ds

via

the

rib

ulo

se

mo

no

ph

osp

ha

te c

ycle

Ga

mm

ap

rote

ob

act

eria

M

em

bra

ne

s a

rra

ng

ed

as

bu

nd

les

of d

isc-

sha

pe

d v

esi

cle

s

La

ck c

om

ple

te c

itric

aci

d c

ycle

O

blig

ate

me

thyl

otr

op

hs

Type II Methanotrophs Assimilate C1 compounds via the serine pathway Alphaproteobacteria Paired membranes that run along periphery of cell


Electron Micrographs of Methanotrophs

Figure 15.14

Type II membrane systemMethylosinus (α Proteobacteria)

Carbon assimilation pathway: serine

Type I membrane systemMethylococcus capsulatans (β-Proteobacteria)

Carbon asimilation pathwy: ribulose monophosphate pathway

Lookup the metabolic pathways for Methylomonas methanica (type II) and Methylococcus capsulatans (type 1) in KEGG (http://www.genome.jp/kegg-bin/show_pathway?scale=0.35&query=methylocystis&map=map01100&scale=0.35&auto_image=&show_description=hide&multi_query=&show_module_list)


Some Characteristics of Methanotrophic Bacteria



W

ide

spre

ad

in a

qu

atic

an

d

terr

est

rial e

nvi

ron

me

nts

M

eth

an

e m

on

oo

xyg

en

ase

a

lso

oxi

diz

es

am

mo

nia

;

com

pe

titiv

e in

tera

ctio

n b

etw

ee

n

sub

stra

tes

C

ert

ain

ma

rine

mu

sse

ls h

ave

sy

mb

iotic

re

latio

nsh

ips

with

m

eth

an

otr

op

hs

Ecology and Isolation of

Methanotrophs


1. P

seu

do

mo

nad

s in

clu

din

g P

seu

do

mo

nas

2. A

ceti

c A

cid

Bac

teri

a

3. F

ree-

Liv

ing

Aer

ob

ic N

itro

gen

-Fix

ing

Bac

teri

a

4. N

eiss

eria

, Ch

rom

ob

acte

riu

m, &

Rel

ativ

es

5. E

nte

ric

Bac

teri

a

6. V

ibri

o, A

livib

rio

, an

d P

ho

tob

acte

riu

m

7. R

icke

ttsi

as

III Aerobic & Facultatively Aerobic ChemoorganotrophicProteobacteria


1. Pseudomonads including Pseudomonas

K

ey

Ge

ne

ra:

P

seu

do

mo

na

s

Bu

rkh

old

eria

Z

ymo

mo

na

s

Xa

nth

om

on

as

A

ll ge

nera

are

:

Str

aigh

t or

curv

ed r

ods

with

pol

ar fl

agel

la

Sta

in g

ram

neg

ativ

e C

hem

oorg

anot

roph

s

Obl

igat

e ae

robe

s

Pos

ses

pola

r fla

gella

Phylogenetically, the group is scattered within the Proteobacteria


Typical Pseudomonad Colonies – eg Burkholderia cepacia

Figure 15.16a

Lophotrichous polar flagella


1. Pseudomonads including Pseudomonas

M

embe

rs o

f the

gen

us P

seud

omon

as a

nd r

elat

ed

gene

ra c

an b

e de

fined

on

the

basi

s of

phy

loge

ny a

nd

phys

iolo

gica

l cha

ract

eris

tics

N

utrit

iona

lly v

ersa

tile

E

colo

gica

lly im

port

ant o

rgan

ism

s in

wat

er a

nd s

oil

S

ome

spec

ies

are

path

ogen

ic

In

clud

es h

uman

opp

ortu

nist

ic p

atho

gens

and

pla

nt

path

ogen

s

R

efer

to th

e ne

xt tw

o sl

ides

for

an o

ver

view


Subgroups and Characteristics of Pseudomonads


Pathogenic Pseudomonads


G

enus

Zym

omon

as

G

en

us

of l

arg

e, g

ram

-ne

ga

tive

ro

ds

tha

t ca

rry

ou

t

vig

oro

us

ferm

en

tatio

n o

f su

ga

rs to

eth

an

ol

U

sed

in p

rod

uct

ion

of f

erm

en

ted

be

vera

ge

s


2. A

cetic

Aci

d B

acte

ria

Org

an

ism

s th

at c

arr

y o

ut c

om

ple

te o

xid

atio

n o

f alc

oh

ols

&

sug

ars

L

eads

to

the

accu

mul

atio

n of

org

anic

aci

ds a

s en

d pr

oduc

ts

M

otil

e r

od

s

Ae

rob

ic

H

igh

tole

ran

ce to

aci

dic

co

nd

itio

ns

C

om

mo

nly

fou

nd

in a

lco

ho

lic ju

ice

s

Use

d in

pro

duct

ion

of v

ineg

ar

S

om

e c

an

syn

the

size

ce

llulo

se

Co

lon

ies

can

be

ide

ntif

ied

on

Ca

CO

3 a

ga

r p

late

s co

nta

inin

g e

tha

no

l


A

var

iety

of s

oil m

icro

bes

are

capa

ble

of fi

xing

N2

aero

bica

lly

Dis

trib

uted

in a

lpha

, bet

a an

d ga

mm

a P

rote

obac

teria

3. Free-Living Aerobic Nitrogen-Fixing Bacteria

The major genera of bacteria capable of fixing N2

nonsymbiotically are Azotobacter, Azospirillium, and Beijerinckia

Azotobacter are large, obligately aerobic rods; can form resting structures (cysts)

All genera produce extensive capsules or slime layers; believed to be important in protecting nitrogenase from O2 (nitrogenase is oxygen-sensitive)


Azotobacter vinelandiiFigure 15.18

Cysts (3 um)

Cells (2 um)


Figure 15.19a

Slime producing Nitrogen2-fixing Bacteria

Cells of Derixia gummosa encased in slime

Beijerinckia species produce colonies with abundant slime


Aci

d-to

lera

nt,

free

-livi

ng N

2 fix

ing

bact

eria

live

in a

cid

soils

Derixia gummosaBeijerinckia indica

(PHB is present)





4. Neisseria, Chromobacterium, and Relatives

N

eiss

eria

, Chr

omob

acte

rium

, and

thei

r re

lativ

es c

an b

e

isol

ated

from

ani

mal

s, a

nd s

ome

spec

ies

of th

is g

roup

are

path

ogen

ic.

N

. gon

orrh

oeae

– g

onor

rhea

N

. men

ingi

tidis

– fa

tal i

nfla

mm

atio

n of

bra

in m

embr

ane


Characteristics of the Genera of Gram-Negative Cocci


Figure 15.21a

Chromobacterium violaceum – produces violacein, a

purple pigment

Colony showing purple colour Structure of the aromatic compoun, violacein


5. Enteric Bacteria (Fam. Enterobacteriaceae)

R

ela

tive

ly h

om

og

en

eo

us

ph

ylo

ge

ne

tic g

rou

p w

ithin

the

G

am

ma

pro

teo

ba

cte

ria

Fa

culta

tive

ae

rob

es

M

otil

e o

r n

on

-mo

tile

, no

nsp

oru

latin

g r

od

s

Po

sse

ss r

ela

tive

ly s

imp

le n

utr

itio

na

l re

qu

irem

en

ts

Fe

rme

nt s

ug

ars

to a

va

riety

of e

nd

pro

du

cts

Enteric bacteria can be separated into two broad groups by the type and proportion of fermentation products generated by anaerobic fermentation of glucose

Mixed-acid fermentators 2,3-butanediol fermentators


Enteric Fermentations

Figure 15.23a


D

iagn

ostic

test

s an

d di

ffere

ntia

l med

ia a

re o

ften

used

to id

entif

y va

rious

gen

era

of e

nter

ic b

acte

ria


Key Diagnostic Reactions Used to Separate Enteric Bacteria


Key Diagnostic Reactions Used to Separate Enteric Bacteria


A Simple Key to the Main Genera of Enteric Bacteria

Figure 15.24


E

sche

richi

a

Un

ive

rsa

l in

ha

bita

nts

of i

nte

stin

al t

ract

of h

um

an

s a

nd

w

arm

-blo

od

ed

an

ima

ls

S

ynth

esiz

e vi

tam

ins

for

host

S

om

e s

tra

ins

are

pa

tho

ge

nic

– c

au

se h

ea

lth p

rob

lem

s

En

tero

pa

tho

ge

nic

(E

PE

C)

– s

urf

ace

K a

ntig

en

s a

llow

s a

ttach

me

nt &

co

lon

isa

tion

E

nte

rhe

mo

rrh

ag

ic (

EH

EC

) –

foo

d /

wa

ter,

O1

57

:H7

(O =

CW

, so

ma

tic, L

PS

; H =

fla

ge

lla p

rote

ins)


S

alm

onel

la a

nd S

hige

lla

Clo

sely

re

late

d t

o E

sch

eri

chia

(D

DH

> 5

0 &

70

%

resp

ect

ive

ly)

U

sua

lly p

ath

og

en

ic

S

. ty

ph

i - t

yph

oid

S

alm

on

ella

is c

ha

ract

eri

zed

imm

un

olo

gic

ally

by

3 s

urf

ace

an

tige

ns:

(u

sed

fo

r tr

ack

ing

ep

ide

mic

s)

O

an

tige

ns

H

an

tige

ns

V

i an

tige

ns,

ou

ter

po

lysa

cch

ari

de

laye

r; t

ypin

g S

. ty

ph

i


P

rote

us

Ge

nu

s co

nta

inin

g r

ap

idly

mo

tile

ce

lls; c

ap

ab

le o

f sw

arm

ing

F

req

ue

nt c

au

se o

f urin

ary

tra

ct in

fect

ion

s in

hu

ma

ns

Copyright © 2009 Pearson Education Inc., publishing as Pearson Benjamin CummingsB

utan

edio

l fer

men

tato

rs –

Ent

erob

acte

r, K

lebs

iella

& S

erra

tia

are

a cl

osel

y re

late

d gr

oup

of o

rgan

ism

s

S

erra

tia

prod

uces

sec

onda

ry m

etab

olite

, pro

digi

osin

, a r

ed

pigm

ent

is

olat

ed fr

om w

ater

, soi

l, in

sect

/ ve

rteb

rate

gut

s,

hum

an in

test

ine.

S

. mar

cesc

ens:

hu

man

pat

hoge

n

infe

ctio

ns fr

om m

edic

al p

roce

dure

s

cont

amin

ant i

n in

trav

enou

s flu

ids


Reactions Used to Separate 2,3-Butanediol Producers


6. Vibrio, Alivibrio, and Photobacterium

T

he V

ibrio

Gro

up

Ce

lls a

re m

otil

e, s

tra

igh

t or

curv

ed

ro

ds

F

acu

ltativ

e a

ero

be

s

Po

sse

ss a

ferm

en

tativ

e m

eta

bo

lism

B

est

kn

ow

n g

en

era

are

Vib

rio, A

livib

rio &

Ph

oto

ba

cte

rium

M

ost

inh

ab

it a

qu

atic

en

viro

nm

en

ts

Some are pathogenic

Some are capable of light production (bioluminescence)

Catalyzed by luciferase, an O2-dependent enzyme

Regulation is mediated by population density (quorum

sensing)


B

acte

rial B

iolu

min

esce

nce

L

igh

t em

issi

on

Mo

st a

re m

arin

e is

ola

tes

(Vib

rio, A

livib

rio,

Ph

oto

ba

cte

rium

) b

ut s

om

e te

rre

stria

l

Ma

y co

lon

ise

sp

eci

aliz

ed

lig

ht o

rga

ns

of s

om

e m

arin

g fi

sh

& s

qu

ids

or

on

de

ad

ski

n o

f cru

sta

cea

n /

fish

V

. ch

ole

ra &

V. v

uln

ificu

s a

re p

ath

og

en

s; c

are

wh

en

h

an

dlin

g lu

min

ou

s b

act

eria

B

iolu

min

esc

en

ce o

nly

wh

en

oxy

ge

n is

pre

sen

t

Lu

xCD

AB

E g

en

e p

rod

uct

s, lu

cife

rase

, oxy

ge

n a

nd

a

po

pu

latio

n d

en

sity

re

spo

nse

(a

cyl h

om

ose

rine

[AH

L],

qu

oru

m s

en

sin

g)

is r

eq

uire

d


Bioluminescent Bacteria as Light Organ Symbionts

Figure 15.27c


7. Rickettsias

R

icke

ttsia

s

S

ma

ll, c

occ

oid

or

rod

-sh

ap

ed

ce

lls

M

ost

ly o

blig

ate

intr

ace

llula

r p

ara

site

s; s

ma

ll g

en

om

e

size

C

an

no

t gro

w o

uts

ide

a h

ost

ce

ll; d

o n

ot s

urv

ive

lon

g

ou

tsid

e th

e h

ost

C

au

sativ

e a

ge

nt o

f se

vera

l hu

ma

n d

ise

ase

s

T

ypic

al p

roca

ryo

tic c

ell

stru

ctu

re


Figure 15.28a

Figure 15.28b

Small 0.3um cells in tissue culture (a). EM of R. popilliae growing in a vacuole in the host beetle, Melolontha melolontha (b)


Characteristics of Rickettsias


W

olba

chia

G

en

us

of r

od

-sh

ap

ed

Alp

ha

pro

teo

ba

cte

ria

In

tra

cellu

lar

pa

rasi

tes

of a

rth

rop

od

inse

cts

A

ffect

the

re

pro

du

ctiv

e fi

tne

ss o

f ho

sts


IV Morphologically Unusual Proteobacteria

1. S

piril

la

2. S

heat

hed

Pro

teob

acte

ria: S

phae

rotil

us &

Lep

toth

rix

3. B

uddi

ng a

nd P

rost

heca

te/S

talk

ed B

acte

ria


1. S

piril

la

Gro

up

of m

otil

e, s

pira

l-sh

ap

ed

Pro

teo

ba

cte

ria:

S

piri

llum

& r

ela

tive

s

Ma

ge

nto

spiri

llum

Bd

ello

vib

rio

Ke

y ta

xon

om

ic fe

atu

res

incl

ud

e

C

ell s

hape

and

siz

e

Num

ber

of p

olar

fla

gella

M

etab

olis

m

P

hysi

olog

y

Eco

logy


Spirilla : Spirillum Volutans

Figure 15.30a


M

agne

tota

ctic

Spi

rilla

H

igh

ly m

otil

e

Is

ola

ted

fro

m fr

esh

wa

ter

ha

bita

ts

M

ag

ne

tota

ctic

mo

vem

en

t – d

irect

ed

by

ma

gn

etic

fie

ld

F

e30

4 m

ag

en

toso

me

& F

e3S

4 (g

reig

ite)


B

deve

llovi

brio

(le

ech)

P

rey

on

oth

er

ba

cte

ria

O

blig

ate

ae

rob

es

M

em

be

rs o

f De

ltap

rote

ob

act

eria

W

ide

spre

ad

in s

oil

an

d w

ate

r, in

clu

din

g m

arin

e e

nvi

ron

me

nts


Developmental Cycle of Bdellevibrio Bacteriovorus

Figure 15.33b


Attachment and Penetration of a Prey Cell by Bdellevibrio

Figure 15.32a


2. Sheathed Proteobacteria: Sphaerotilus & Leptothrix

S

heat

hed

Bac

teria

F

ilam

en

tou

s B

eta

pro

teo

ba

cte

ria

U

niq

ue

life

cyc

le in

wh

ich

fla

ge

llate

d s

wa

rme

r ce

lls

form

with

in a

lon

g tu

be

or

she

ath

U

nder

unf

avor

able

con

ditio

ns,

swar

mer

cel

ls m

ove

out

to e

xplo

re n

ew e

nviro

nmen

ts

C

om

mo

n in

fre

shw

ate

r h

ab

itats

ric

h in

org

an

ic m

atte

r


Sheathed Proteobacteria: Sphaerotilus & Leptothrix

S

phae

rotil

us

N

utr

itio

na

lly v

ers

atil

e

A

ble

to u

se s

impl

e or

gani

c co

mpo

unds

O

blig

ate

ae

rob

es

C

ells

with

in th

e s

he

ath

div

ide

by

bin

ary

fiss

ion

E

vent

ually

sw

arm

er c

ells

are

libe

rate

d fr

om s

heat

hs


Sphaerotilus Natans

Figure 15.34a


Sphaerotilus Natans

Figure 15.34b


Sphaerotilus Natans

Figure 15.34c


Sheathed Proteobacteria: Sphaerotilus & Leptothrix

S

phae

rotil

us a

nd L

epto

thrix

are

abl

e to

pre

cipi

tate

iron

oxid

es


Leptothrix and Iron Precipitation

Figure 15.35


Budding and Prosthecate/Stalked Bacteria

3. B

uddi

ng a

nd P

rost

heca

te/S

talk

ed B

acte

ria

L

arg

e a

nd

he

tero

ge

ne

ou

s g

rou

p

P

rima

rily

Alp

ha

pro

teo

ba

cte

ria

F

orm

va

riou

s ki

nd

s o

f cyt

op

lasm

ic e

xtru

sio

ns

bo

un

de

d

by

a c

ell

wa

ll (c

olle

ctiv

ely

ca

lled

pro

sth

eca

e)


Features of Stalked, Appendaged and Budding Bacteria


Prosthecate Bacteria

Figure 15.36a



Figure 15.36b



Figure 15.36c


Cell Division

Figure 15.37



B

uddi

ng B

acte

ria

D

ivid

e a

s a

re

sult

of u

ne

qu

al c

ell

gro

wth

T

wo

we

ll-st

ud

ied

ge

ne

ra

H

ypho

mic

robi

um (

chem

oorg

anot

roph

ic)

R

hodo

mic

robi

um (

phot

otro

phic

)


Stages in the Hyphomicrobium Cell Cycle

Figure 15.38


Morphology of Hyphomicrobium

Figure 15.39a


Morphology of Hyphomicrobium

Figure 15.39b



P

rost

heca

te a

nd S

talk

ed B

acte

ria

A

pp

en

da

ge

d b

act

eria

tha

t atta

ch to

pa

rtic

ula

te m

atte

r,

pla

nt m

ate

rial,

an

d o

the

r m

icro

be

s in

aq

ua

tic

en

viro

nm

en

ts

A

pp

en

da

ge

s in

cre

ase

su

rfa

ce-t

o-v

olu

me

ra

tio o

f th

e

cells


Stalked Bacteria

Figure 15.40a


Stalked Bacteria

Figure 15.40b


Stalked Bacteria

Figure 15.40c



C

aulo

bact

er

C

he

mo

org

an

otr

op

h

P

rod

uce

s a

cyt

op

lasm

-fill

ed

sta

lk

O

ften

se

en

on

su

rfa

ces

in a

qu

atic

en

viro

nm

en

ts w

ith

sta

lks

of s

eve

ral c

ells

atta

che

d to

form

ro

sette

s

H

old

fast

str

uct

ure

pre

sen

t on

the

en

d o

f th

e s

talk

use

d

for

atta

chm

en

t

M

od

el s

yste

m fo

r ce

ll d

ivis

ion

an

d d

eve

lop

me

nt


Growth of Caulobacter

Figure 15.41


15.16 Budding and Prosthecate/Stalked Bacteria

G

allio

nella

C

he

mo

lith

otr

op

hic

iro

n-o

xid

izin

g b

act

eria

P

oss

ess

twis

ted

sta

lk-li

ke s

tru

ctu

re c

om

po

sed

of f

err

ic

hyd

roxi

de

C

om

mo

n in

wa

ters

dra

inin

g b

og

s, ir

on

sp

ring

s, a

nd

oth

er

en

viro

nm

en

ts r

ich

in F

e2+


The Neutrophilic Ferrous Iron Oxidizer, Gallione Ferruginea

Figure 15.42a


The Neutrophilic Ferrous Iron Oxidizer, Gallione Ferruginea

Figure 15.42b


V. Delta- and Epsilonproteobacteria

15

.17

Glid

ing

Myx

obac

teria

15

.18

Sul

fate

- an

d S

ulfu

r-R

educ

ing

Pro

teob

acte

ria

15

.19

The

Eps

ilonp

rote

obac

teria


15.17 Gliding Myxobacteria

G

lidin

g

A

form

of m

otil

ity e

xhib

ited

by

som

e b

act

eria

G

lidin

g B

acte

ria

A

re ty

pic

ally

eith

er

lon

g r

od

s o

r fil

am

en

ts

L

ack

fla

ge

lla, b

ut c

an

mo

ve w

he

n in

co

nta

ct w

ith

surf

ace

s


Classification of the Fruiting Myxobacteria


Classification of the Fruiting Myxobacteria



M

yxob

acte

ria

G

rou

p o

f glid

ing

ba

cte

ria th

at f

orm

mu

ltice

llula

r

stru

ctu

res

(fru

itin

g b

od

ies)

an

d s

ho

w c

om

ple

x

de

velo

pm

en

tal l

ife c

ycle

s

D

elta

pro

teo

ba

cte

ria

C

he

mo

org

an

otr

op

hic

so

il b

act

eria

L

ifest

yle

incl

ud

es

con

sum

ptio

n o

f de

ad

org

an

ic m

atte

r

or

oth

er

ba

cte

rial c

ells



F

ruiti

ng m

yxob

acte

ria e

xhib

it co

mpl

ex b

ehav

iora

l pa

ttern

s an

d lif

e cy

cles

V

eg

eta

tive

ce

lls a

re s

imp

le, n

on

flag

ella

ted

ro

ds

tha

t

glid

e a

cro

ss s

urf

ace

s a

nd

ob

tain

the

ir n

utr

ien

ts

prim

aril

y b

y ly

sin

g o

the

r b

act

eria

an

d u

tiliz

ing

re

lea

sed

nu

trie

nts

U

nder

app

ropr

iate

con

ditio

ns,

vege

tativ

e ce

lls

aggr

egat

e, c

onst

ruct

fru

iting

bod

ies,

and

und

ergo

diff

eren

tiatio

n in

to m

yxos

pore

s


Myxococcus

Figure 15.43a


Myxococcus

Figure 15.43b


Stigmatella aurantiaca

Figure 15.44a


Stigmatella aurantiaca

Figure 15.44b


Fruiting Bodies of Three Species of Fruiting Myxobacteria

Figure 15.45a



Figure 15.45b



Figure 15.45c



T

he li

fe c

ycle

of f

ruiti

ng m

yxob

acte

rium

is c

ompl

ex


Life Cycle of Myxococcus xanthus

Figure 15.46


Swarming in Myxococcus

Figure 15.47a


Swarming in Myxococcus

Figure 15.47b


Fruiting Body Formation in Chondromyces crocatus

Figure 15.48a



Figure 15.48b



Figure 15.48c



Figure 15.48d


Sulfate- and Sulfur-Reducing Proteobacteria

D

issi

mila

tive

sulfa

te-

and

sulfu

r-re

duci

ng b

acte

ria

O

ver

40

ge

ne

ra o

f De

ltap

rote

ob

act

eria

U

se S

O42-

an

d S

o a

s e

lect

ron

acc

ep

tors

an

d o

rga

nic

com

po

un

ds

or

H2

as

ele

ctro

n d

on

ors

H

2S

is a

n en

d pr

oduc

t Most obligate anaerobes

Widespread in aquatic and terrestrial environments


Sulfate- and Sulfur-Reducing Proteobacteria

P

hysi

olog

y of

sul

fate

-red

ucin

g ba

cter

ia

G

rou

p I

O

xidi

ze la

ctat

e, p

yruv

ate,

or

etha

nol t

o ac

etat

e an

d

excr

ete

fatt

y ac

id a

s an

end

pro

duct

G

rou

p II

O

xidi

ze f

atty

aci

ds,

lact

ate,

suc

cina

te,

and

benz

oate

to

CO

2


Sulfate- and Sulfur- Reducing Bacteria


Enrichment Culture of Sulfate-Reducing Bacteria

Figure 15.49g


The Epsilonproteobacteria

E

psilo

npro

teob

acte

ria

A

bu

nd

an

t in

oxi

c–a

no

xic

inte

rfa

ces

in s

ulfu

r-ric

h

en

viro

nm

en

ts

e.

g.,

hydr

othe

rmal

ven

ts

M

an

y a

re a

uto

tro

ph

s

U

sing

H2,

form

ate,

sul

fide,

or

thio

sulp

hate

as

elec

tron

dono

r

P

ath

og

en

ic a

nd

no

n-p

ath

og

en

ic r

ep

rese

nta

tive

s


Characteristics of Key Genera of Epsilonproteobacteria

Documents

Bacteria : The Proteobacteria