Microbiology: Koch's Postulates, Bacterial Cell Lineages, and ATP Production

Koch's 4 postulates

- pathogen must be present in all diseased animals and absent in all healthy animals

- pathogen must grow in a pure culture

- The cells of the pure culture must produce disease when injected into a healthy animal

- The pathogen should be isolated from the newly infected animal and proven that it is the same as the first organism cultured ( grow in a culture again)

What are the 3 groups of cellular lineages ( domains of life)

1 .bacteria

2. archaea

3. Eukarya

How much net ATP is produced by glucose by steps of CR

- glyclysis ( substrate level phosphorylation) 2

- citric acid cycle (substrate-level phosphorylation) 2

- proton gradient driven by the CA cycle 28

How many ATPs are unaccounted for, and how are they made

6, glyclysis ( NADH H+)

Why is it essential for a bacterial cell to reduce pyruvate during fermentation?

To regenerate NAD+

In fermentation, pyruvate is reduced to lactate or ethanol in order to regenerate What molecule?

NAD+

during fermentation, which of the following is true?

NAD+ must be regenerated by reducing pyruvate

A cell that uses CO2 as its source of carbon is an

Organisms that synthesize all of their organic compounds from CO2 are known as:

Autotroph

a carbohydrate has a, carbon, oxygen hydrogen ratio of

1:2:1

The ultimate downfall of the theory of spontaneous generation was the result of

work by

Pastuer

who was given credit with disproving the concept of spanatious generation?

Louis Pasteur

what are the 3 catabolic classes of microorganisms:

1. chemooragnotroph

2, chemilithotroph

3. phototroph

What are the 2 anabolic classes of microoganisms

1. heterotroph

2. autotroph

In many of the chemolithotrophic (inorganic) species, sulfur compounds are ________to fuel either metabolic fxns or energy generation

oxidized

the complenet of genes within a cell

genome

The largest phylum of bacteria

Proteobacteria

DNA replication always proceeds from the

______

of the previously added nucleotide.

5' phosphate, 3' hydroxyl

Polynucleotides consist of nucleotides covalently bonded via phosphate from the

3' carbon of one sugar to the 5' carbon of the adjacent sugar

In oxidative respiration as carried out by chemoorganotrophs,

What is the source of protons used to generate PMF?

Where is this source of protons located?

H20

cytoplasm

Name the 2 functional groups below. Give one example of a structure where each

functional group is commonly found in prokaryotes.

Ether Archaea membranes

Ester Bacteria & Eukarya cell membranes

In a polypeptide, the linear arrangement of the amino acids is the

structure, while the interactions of the R groups result in the

structure

primary, secondary

What is the ultimate purpose (as discussed in class) for the uptake of oxygen by

aerobic respiratory organisms?

Pumping Protons (generation of ATP) / Generate proton motive force?

True or False: the free energy of formation of an element (delta G) is always

ZERO

true

most compounds have a delta G that is

negative

___________ and

_______________

donors in the electron transport system.

serve as hydrogen atom acceptors and electron

Quinones and Flavoproteins

T/F: The greater the difference in reduction potential between electron donor and

electron acceptor , the more likely a reaction is to occur

true

What statement is true

Prosthetic groups are generally bound tightly to their respective

enzymes

8.Amino acids fall into one of four separate classes depending on differences in

their R groups. Indicate the 4 classes.

1. nonpolar

2. nonionizable polar

3. ionzible acidic

4. ionizable basic

NONPOLAR

Glycine

Valine

Alanine

Leucine

Isoleucine

Methionine

Tryptophan

Proline

nonionizable polar

Serine

Asparagine

Threonine

Glutamine

Cysteine

Selenocysteine

Tyrosine

IONIZABLE BASIC:

Glutamic Acid

Glutamate

Aspartate

30.Anabolic Reactions are

and are

_____________

___________________

Energy consuming, Reductions

Catabolic Reactions are

and are

_____________

___________________

Energy yielding, Oxidations

Which of the following statements is false regarding the cytoplasmic membranes of

Archaea?

They contain fatty acids (Bacteria only* - Archaea have isoprenoid chains

Which are hydrocarbon chains)

During fermentation, NADH is oxidized resulting in the production of fermentation

end products (such as lactic acid or ethanol). What substance is reduced by this

process?

Pyruvate

T/F: Chemolithotrophs derive their energy from organic nutrients and their carbon

from CO2

FALSE (inorganic)

In chemolithotrophy:

Carbon is commonly reduced anabolically (fixed)

- Energy is derived from the reduction of inorganic molecules

(Both choices)

What are the 4 kinds of micromolecules in microbial cells

Proteins

Polysaccharides

Lipids

Nucleic Acids

Which of the following types of macromolecule accounts for the greatest percentage

of total dry weight?

proteins

P vs E, what has extracromosomal DNA?, nucleous?, cytoplasm membrane?

Contain extra-chromosomal DNA: Prokaryotes

(Reproduce by fission)

Nucleus Eukaryotes

Contain cytoplasmic membrane Both

What are 3 processes driven by the proton motive force?

1) ATP production

2) Flagella motility

3) Chemiosmosis

The proton motive force is directly responsible for driving many energy-requiring

functions in the cell including _______________

and

____________________

and biosynthesis

of

___________

Transport, Flagella motility, ATP

The standard evolutionary chronometer used to determine relationships between

prokaryotes is based on what molecule?

16s rRNA

. The main purpose of shuttling electrons through the electron transport system is to

generate proton motive force.

a) Where do the electrons for this process come from? (assume

organoheterotrophy)

What is the principal source of protons involved in this process?

glucose, H20

The structure of peptidoglycan in gram (+) bacteria is distinguished from that

of gram (-) bacteria by:

the presence of an interbridge

T/F: The structure of peptidoglycan is identical in gram-negative and gram-positive

bacteria?

False

The outer leaf of the lipid bilayer of the gram negative outer membrane is composed

principally of

_____________________

Lipopolysaccharide

46. The principal component (by mass) of lipopolysaccharides is

sugar

List the 3 components of a Lipopolysaccharide:

1. Lipid A

2. core polysaccharide

3. O side chain, O antigen

48.List the 6 common morphologies of bacteria.

1) Coccus

2) Rod

3) Spirillum

4) Spirochete

5) Apphendaged

6) Filamentous

The largest phylum of bacteria is the

Proteobacteria

T/F: Archaea are more closely related to Eukarya than to Bacteria

True, Nuclear DNA and genetic machinery is very similar

.Dipicolinic acid is a unique component of

_

endospores

What component of the bacterial endospore is responsible for stabilizing DNA

during dormancy AND acting as a nutrient source during germination?

SASPs ( small acid-soluble protein)

53. Name 2 carriers in the e- transport system that are able to carry both e- and protons.

NADH & Quinones

Which of the following is the most abundant type of molecule in bacterial cells?

Proteins

Phosphorylation of glucose upon entry into the bacterial cell is an example of what

type of transport?

Group translocation

bacterial growth medium in which one or more of the ingredients is not fully

characterized is known as a

medium.

undifined / complex

In microbial metabolism, the terminal electron acceptor is:

The last electron acceptor in a series of oxidation-reduction reactions

An increase in the volume of a bacterial cell due to growth results in

a decrease in the surface to volume ratio

*** inverse realshinship

If the diameter of a sphere increased, the surface to volume ratio of the sphere

dercreased

T/F: Teichoic acids impart a

NEGATIVE CHARGE TO GRAM POSITIVE

Negatively charged molecules that are partially responsible for the negative charge

of the gram-positive bacterial cell wall are called

__________________

Teichoic Acid

How many rings are found in the base of the flagella of gram-positive bacteria?

2

The citric acid cycle plays 2 major roles in the cell; these are:

ATP synthesis and biosynthesis

Which of the following statements is false?

Pili and flagella are hollow protein tubes whereas fimbriae are

composed of peptidoglycan -------(not comp of peptidoglycan)

Which group of microorganisms is not considered to be living cells?

Viruses

Which of the following is not true of viruses?

Able to carry out independent metabolism- need host cell

.Circle the correct answer . The structure to the right is:

Purine base (purines A, G have 2 ----- pyrimidines U, C, T have 1)

ist 2 nucleotides in DNA that are pyrimidines

C & T

The lipid membranes of Archaea are able to remain intact at high

temperatures due to the

_______________ linkage between glycerol and their

hydrophobic side chains.

Ether

(Ether - archaeal membranes, Ester - bacteria & eukarya membranes)

T/F Archaea's Phospholipids form monolayers or bilayers with the glycerol

component of the molecule bound to the fatty acids via an Ether linkag

False , Not fatty acids in archaea isoprene polymers - long-chain hydrocarbon)

The template for RNA polymerase in transcription is

DNA

.Name two genera of bacteria that produce endospores

Bacillus & Clostridium

T/F: A negative ∆Go' is indicative for an energy consuming reaction.

(Would be

releasing) FALSE

Indicate the type of transport system that involves the modification of the

transported substance upon transport into the cytoplasm.

Phosphotransferase system

In aerobic respiration (of glucose), the primary e- donor is

terminal electron acceptor is

__________________

Glucose, O2

In the reaction 1/2 O2 + 2e- + 2H+ H2O, oxygen is being __________________

reduced

n the reaction H2 H+ + e-, H2 is being ___________________

Oxidized ( lost e-)

The half reaction 1/2 O2 H20 = +.82 V indicates that oxygen has a

tendency to donate electrons.

low

a - charge would be high

Non-Heme Iron-Sulfur proteins carry _____ to the electron transport chain

Cytochromes

ist the 3 classes of membrane-transporting systems found in bacteria:

1) Simple Transport

2) Group Translocation

3) ABC Transport System

In Symport, a substance (X) is transported across the cytoplasmic membrane

With a substance (Y) that is entering along a concentration gradient

Antiport, a substance (X) is transported across the cytoplasmic membrane

In the opposite direction of a substance (Y) that is leaving along a

concentration gradient

NAD+/NADH are involved primarily in _______ reactions

NADP+/NADPH are involved in ________

reactions

Catabolic , Anabolic

The bacterial flagellar rotor and ATP synthase protein complex are both driven by

what?

Proton Motor Force

The process by which glucose is synthesized within the cells i

glucogeneisis

An organism that grows optimally at 15°C or below is called a

Psychrophile (opposite is thermophile)

T/F: The optimal temperature for growth of a microorganism is always nearer the

minimum temperature than the maximum temperature

False

Indicate a mechanism/adaptation (as discussed in class) by which

Hyperthermophilic prokaryotes are able to cope with high temperatures.

High # of G---C bonds in DNA ( harder to break)

Which statement is NOT true?

The 16s rRNA catalyzes the formation of the peptide bond

Circle all statements that are true of the chromosomes of prokaryotes:

1. usually circular

2. has supercoiled domains

3. Replication is tied to the division cycle

ATP synthase uses the flow of protons to rotate the ___________subunit of the F0

component inducing conformational changes in the beta subunit of the F1

component allowing binding of ADP + Pi and conversion to ATP

ɣ Gamma

Hopenoids and sterols confer rigidity to which biological structure?

cell membarne

Rigidity is provided to the bacterial cell by _____________________

permeability barrier to the

____________________

Peptidoglycan (/cell wall) cytoplasmic

membrane

Which is the most numerous on the surface of a bacterial cell: flagella, fimbriae, or

pili?

Fimbrea

T/F: The beta-lactam antibiotics (penicillin) inhibit the transpeptidase reaction by

interfering with the linkage of D-alanine residue

TRUE

In proteins, tertiary structure arises from:

Covalent bonding btw diff regions of a single polypeptide chain

In proteins, covalent bonding between different regions of a single peptide chain

confers:

Tertiary structure

Purines Vs Pyrimindines

A and G = purines ( larger double ring structure)

T and C U are Pyrimidines smaller single ring