學(xué)姐-微生物課件02-1lecture2an overview of microbial

Shanghai

Jiao

Tong

UniversityI.

Cell

Structure

andEvolutionaryHistoryMost

of

the

microbial

cells

are

prokaryotic

cells原核細(xì)胞Some

micro真核細(xì)胞Some

micro胞生物anisms

have

eukaryotic

cell

structureanisms

are

non-cellular

life

forms非細(xì)Shanghai

Jiao

Tong

University2.1

Elements

of

Cell

and

Viral

StructuresFig.

2.1

Internal

structure

of

microbialcells.

Prokaryote

cells

lackatrue

nucleus

and anelles原核細(xì)胞無(wú)真的細(xì)胞核及細(xì)胞器anellesFig.2.1b

Eukaryote

cells

possess

a

true

nucleus

and真核生物具有細(xì)胞核及細(xì)胞器Eukaryotic

cells真核Algae藻類(lèi)Fungi真菌Molds絲狀真菌YeastsProtozoa原生生物Non-cellular

life

forms:particles粒子Fig.

2.3

A

singleparticle

isabout

65nmmeter.Shanghai

Jiao

Tong

University2.2

Arrangement

of

DNA

in

Microbial

Cells:Bacterial

NucleoidBacteria

contain

one

long

circular

DNA-chromosome.

細(xì)菌的類(lèi)核包含一條環(huán)狀的DNA(

)The

DNA

can

be

1mm

longThe

cell

is

usually

2-3m

longShanghai

Jiao

Tong

UniversityFig.

2.4

The

term

nucleoid

is

used

to

describe

aggregated

DNA/bacterial

chromosome

in

the

prokaryotic

cell

which

can

be

observedunder

special

staining

conditions

類(lèi)核：用于描述原核細(xì)胞中在一起的DNAFig.2.4

By

gently

lysing

the

cells,

the

highly

compacted

nucleoid

willemerge

intact. (Arrows

point

to

edge

of

strands).

采用極輕微

的細(xì)胞裂解方法，就可以得到一團(tuán)完整展開(kāi)的類(lèi)核DNA。The

DNA

in

both

the

open

circle

and

supercoiled

chromosome

ispresent

in

a

covalently

closed

form.超螺旋The

double-stranded

DNA

in

E.

coli

chromosome

contains

over50

supercoiled

s.超螺旋域Shanghai

Jiao

Tong

UniversityNucleus

vs.Nucleoid

細(xì)胞核與擬核In

eukaryotes,

DNA

is

present

in

linear

moleculeswithin

the

nucleus,

packaged

and anized

inchromosomes.Genome

sizes

vary

greatly

rangingfrom

es

with

the

smallesttoalgaeandvertebratespossessingthegreatestamount.基因組最小,藻類(lèi)、脊椎動(dòng)物最大Shanghai

Jiao

Tong

University2.3

Tree

of

LifeEvolution

is

the

change

in

a

line

of

descent

overtime

leading

to

new

species

or

varieties.進(jìn)化Evolutionary

relationships

between

life

forms

arethesubject

of

phylogeny.系統(tǒng)發(fā)生學(xué)Phylogenetic

relationships

can

be

deduced

bycomparing

sequences

of

certain

macromolecules(ribosomal

RNAs).p.26Fig.

2.6

Ribosomal

RNA

gene

sequencing

and

phylogeny.（e) gorithm

makes

a

tree

that

shows

the

differences

in

rRNA

sequencebetween

the

anisms yzed.對(duì)比不同生物之間rRNA的差異,可得到描述其兩兩差異的樹(shù)狀結(jié)構(gòu).Threes

of

LifeCellular

evolution

as

deduced

from

ribosomal

RNA

sequencing. The

figureconsists

ofthree

s

of anisms:the

bacteria

andthe

Archaea,cells

of

whichare

prokaryotic,andtheEukarya

(eukaryotes).三域:細(xì)菌,古生菌與真核生物.Fig.2.7

phylogenetic

tree

of

life

as

defined

by

comparativeribosomalRNAsequencing比較核糖體RNA序列得到的生命系統(tǒng)發(fā)生學(xué)進(jìn)化樹(shù)Microbial

cells:

Bacteriapathogenssoils,

water,

animal

intestine,

etcdifferent

energy

sources,

carbon

sources,

oxygendemandsShanghai

Jiao

Tong

UniversityMicrobial

cells:

ArchaeaMany

are

extremephiles,

anerobicBoiling-hot

springFreezing-Antarctic

seaRadioactive

wastesSalty,

acidic,

alkaline

soils

or

waterThey

can

be

found

almost

anywhere

on

earthShanghai

Jiao

Tong

UniversityPART

IIMicrobial

Diversityanisms,2.4

Physiological

Diversity

of

Micro微生物的生理多樣性p.28All

cells

needCchaermbooonrgaannodtrophs

obtain

theirChemolithotrophsobtain

their

energyPhototrophscontain

pigmentsthat

allow

themtouse

light

as

anenergy

source.光能營(yíng)養(yǎng)型生物含有色素,可使用光能為能量來(lái)源.Shanghai

Jiao

Tong

UniversityAutotrophs

and

heterotrophsAutotrophs

use

CO2

as

their

carbon

source,whereasheterotrophsuse

aniccarbon.自養(yǎng)型生物以CO2為碳源,異養(yǎng)型生物以有機(jī)碳為碳源.Shanghai

Jiao

Tong

University2.5

Prokaryotic

Diversity,

p.

30Several

lineages

are

present

in

the

sBacteria

and

Archaea,and

an

enormous

diversity

ofcell

morphologies

and

physiologies

are

representedthere.細(xì)胞形態(tài)及生理的多樣性The

Proteobacteria

is

the

largest

division(called

aphylum門(mén))of

Bacteria

(Figure

2.9).變形桿菌Shanghai

Jiao

Tong

UniversityFig.

2.9

Detailed

phylogenetics

tree

of

Bacteria產(chǎn)液菌屬棲熱袍菌屬無(wú)硫綠細(xì)菌異常球菌螺旋體綠硫細(xì)菌浮霉?fàn)罹鷮偎{(lán)細(xì)菌變形桿菌革蘭氏陽(yáng)性細(xì)菌The

Cyanobacteria

are

phylogenetic

relatives

of

gram-positive

bacteria

and

areoxygenic

phototrophs.Shanghai

Jiao

Tong

UniversityFigure

2.12 Filamentous

cyanobacteria

絲狀藍(lán)細(xì)菌The

Cyanobacteria

are

phylogenetic

relatives

of

gram-positive

bacteria

andare

oxygenic

phototrophs.Shanghai

Jiao

Tong

UniversityFigure

2.18There

are

two

lineages

of

Archaea,the

Euryarchaeota

and

theCrenarchaeota.古生菌有廣古生菌界與泉古生菌界.2.6

Eukaryotic

Micro anisms,

p.

35Microbial

eukaryotes

are

a

diverse

group

thatincludes

algae,protozoa,

fungi,and

slime

molds.真核微生物包括有藻類(lèi),原生生物,真菌,和粘液菌類(lèi).Cells

of

algae

and

fungi

have

cell

walls,

whereas

theprotozoa

do

not.Shanghai

Jiao

Tong

UniversityMoldsMushroomsYeastsSlime

moldsAlgaeProtozoaFungiEukaryotic

MicroanismsShanghai

Jiao

Tong

UniversityFungi

are

heterotrophic

eukaryotic

micro

anisms.They

are

nonphotosynthetic

and

typically

formreproductive

spores.真菌為異養(yǎng)真核生物,非光合,一般可形成繁殖的孢子.Algae

are

phototrophic

eukaryotes

that

containphotosynthetic

pigments

within

chloroplast藻類(lèi)是光合真核生物,在其葉綠體中有光合色素.Protozoa

are

animallike

protists

exhibitingheterotrophic

nutrition

and

they

can

be

defined

asusually

motile

eukaryotic

unicellular

micro

anisms.原生生物是類(lèi)似動(dòng)物的

異養(yǎng)真核生物,

常定義為可運(yùn)動(dòng)的單細(xì)胞真核微生物.Figure

2.22Detailed

phylogenetic

tree

of

Eukarya雙微孢子蟲(chóng)鞭毛蟲(chóng)粘質(zhì)霉菌卵菌褐藻纖毛蟲(chóng)Shanghai

Jiao

Tong

UniversityAlgae

藻類(lèi)Fungi