BACTERIAL BIOCHEMISTRY METABOLISM

Question 1

Study of the vital life processes of microorganisms

• Nutritional needs
• Metabolic pathways
• Reproduction, growth and death

Answer 1

MICROBIAL PHYSIOLOGY

Question 2

*All living protoplasm contains 6 major chemical elements:
C, H, O, N, P, S

*Combinations of all these elements make up the
macromolecules: carbohydrates, proteins, lipids and
nucleic acids

*To build necessary cellular materials, every organism
requires a source/s of energy, carbon and other nutritional
requirements

Answer 2

Nutritional Requirements

Question 3

ENERGY SOURCE

light

Answer 3

PHOTOTROPHS

Question 4

ENERGY SOURCE

chemicals

Answer 4

CHEMOTROPHS

Question 5

inorganic materials

Answer 5

Chemolitotrophs

Question 6

organic materials

Answer 6

Chemoorganotrophs

Question 7

CO2 as their sole source of carbon

Examples: plants, algae and cyanobacteria

Answer 7

AUTOTROPHS

Question 8

CARBON SOURCE

Answer 8

AUTOTROPHS

HETEROTROPHS

Question 9

organic compounds
other than CO2
Examples: humans, animals, fungi, bacteria and
protozoa

Answer 9

HETEROTROPHS

Question 10

use light as energy source and CO2 as carbon source

Plants, algae, cyanobacteria, purple and green sulfur bacteria

Answer 10

PHOTOAUTOTROPHS

Question 11

use light as energy source and organic compounds aside from CO2 as carbon
source

Purple nonsulfur and green nonsulfur bacteria

Answer 11

PHOTOHETEROTROPHS

Question 12

Use electrons from reduced inorganic compounds as a source of energy and
they use CO2 as their main source of carbon

Thiobacillus thiooxidans, Nitrosomonas, Nitrobacter, Hydrogenomonas

Answer 12

CHEMOAUTOTROPHS

Question 13

use chemicals as energy source and organic compounds other than CO2 as carbon
source (all clinically impt bacteria are of this group)

Animals, protozoa, fungi and most bacteria

Answer 13

CHEMOHETEROTOTROPHS

Question 14

Biochemical reactions or cellular processes for survival and

replication. Involves:
* Break down of organic compounds
* Synthesis of new bacterial parts

Answer 14

BACTERIAL METABOLISM

Question 15

Energy is generated from these metabolic breakdowns and all
these biochemical reactions are controlled by specific
enzymes

Answer 15

BACTERIAL METABOLISM

Question 16

Anaerobic process carried by both obligate and facultative

anaerobes; electron acceptor is an organic compound

Answer 16

Fermentation

Question 17

When fermentation occurs, a mixture of end products is

accumulated like: lactate, butyrate, ethanol, acetoin

Answer 17

Fermentation

Question 18

In dx micro: fermentation could indicate any type of
utilization (fermentative or oxidative) of a CHO (sugar)
with the resulting production of an acid pH

Answer 18

Fermentation

Question 19

These pathways break down GLUCOSE to form
PYRUVIC ACID; precursor metabolites are also produced
by these 3 central pathways:
1.Embden-Meyerhof-Parnas (EMP)Pathway
2.Entner-Doudoroff Pathway
3.Pentose Phosphate Shunt

Answer 19

Biochemical Pathways

Question 20

Fermentation pathways of microbes in the human host:

1. Alcoholic fermentation
2. Homolactic fermentation
3. Heterolactic fermentati0n
4. Propionic acid fermentation
5. Mixed acid fermentation
6. Butanediol fermentation
7. Butyric acid fermentation

Answer 20

Anaerobic Utilization of Pyruvic

Acid (Fermentation)

Question 21

cycle is the most important
pathway for the complete oxidation of a substrate under
aerobic conditions

Answer 21

Krebs/TCA/Citric acid

Question 22

Krebs/TCA/Citric acid cycle is the most important
pathway for the complete oxidation of a substrate under
aerobic conditions

Answer 22

Aerobic Utlization of Pyruvic acid

Oxidation

Question 23

In this cycle, pyruvate is oxidized, carbon skeletons are
created, and the e- are passed through the electron
transport chain (ETC) and used to generate energy in the
form of ATP

Answer 23

Aerobic Utlization of Pyruvic acid

Oxidation

Question 24

This cycle results in the productionn of acid and CO2

Answer 24

Aerobic Utlization of Pyruvic acid

Oxidation

Question 25

Process of bacterial heredity and variation

Answer 25

BACTERIAL GENETICS

Question 26

3 major aspects of microbial genetics:

Answer 26

1.Structure and organization of genetic material 2.Replication and expression of genetic information 3.Mechanisms by w/c genetic information is changed and exchanged among bacteria

Question 27

where hereditary information is encoded; DNA and RNA; made up of a 5-carbon sugar, nitrogen-containing “base” and a phosphate group

Answer 27

Nucleic acids

Question 28

sugar, PO4 and bases of nucleic acids; DNA and RNA | are nucleotide polymers (chains/strands)

Answer 28

Nucleotide

Question 29

order of bases along a DNA or RNA strand

Answer 29

Base Sequence

Question 30

exists as double-stranded molecules; carry genetic code

Answer 30

DNA

Question 31

exists as a single-stranded molecule; plays a key role in gene expression

Answer 31

RNA

Question 32

DNA sequence that encodes for a specific product (RNA or protein)

Answer 32

Gene

Question 33

all genes taken together within an organism

Answer 33

Genome

Question 34

* when a genome is organized into a single discrete unit; * gene carrier; * Haploid - only one chromosome is present in a bacterial nucleoid * a single circle containing about 4000 kbp (kilobase pairs) of DNA

Answer 34

CHROMOSOME

Question 35

only one chromosome is present in a bacterial nucleoid

Answer 35

Haploid

Question 36

extra-chromosomal genetic elements; miniature | chromosomes; replicates independently from the chromosome

Answer 36

Plasmids

Question 37

Bacterial genes are carried on

Answer 37

Bacterial chromosome Plasmids | Transposable elements

Question 38

pieces of DNA that move from one genetic element to another; they do not exist as separate entities since they must be incorporated into a plasmid or chromosome; “jumping genes” ; two types:

Answer 38

Transposable elements

Question 39

contains genes that encode information | required for movement among plasmids and chromosomes

Answer 39

Insertion sequence

Question 40

contains genes for movement as well as genes that | encode for other features like drug resistance

Answer 40

Transposon

Question 41

during bacterial cell division, the genome must be replicated so that each daughter cell receives the same complement of functional DNA from the parent cell

Answer 41

Replication of Genetic Information

Question 42

is the processing of information encoded in genetic elements (chromosome, plasmid, transposon) that results in the production of biochemical products

Answer 42

Expression of Genetic Information

Question 43

copying of the DNA molecule by mRNA Synthesis of mRNA, tRNA and rRNA RNA polymerase – enzyme central to the transcription process

Answer 43

Transcription (synthesis of RNA)

Question 44

-mRNA codons are read, amino acids are brought to the mRNA strand and polypeptides (proteins) are produced at the ribosomes -Initiation, elongation and termination -Translation ends with the production of a protein

Answer 44

Translation (synthesis of protein)

Question 45

Genetic change in bacteria is accomplished by 3 basic mechanisms:

Answer 45

1 Mutation 2 Genetic recombination 3 Gene exchange

Question 46

Change in the original nucleotide sequence of a gene/s (genotype) This change may involve a single DNA base w/in a gene, an entire gene, or several genes Usually results in insertion of a different amino acid into a protein resulting to an altered phenotype

Answer 46

Mutation

Question 47

DNA segment/s are physically exchanged/transferred from a donor cell to the recipient cell;

Answer 47

DNA segment/s are physically exchanged/transferred from a donor cell to the recipient cell;

Question 48

``` is a characteristic w/ members of the genera: Haemophilus Streptococcus Neisseria ```

Answer 48

Competence

Question 49

``` Recipient cell directly takes up naked DNA released from the donor cell altering its genotype ```

Answer 49

Transformation

Question 50

DNA of donor cell that contains bacteriophages is transferred to the recipient cell; phage mediated

Answer 50

Transduction

Question 51

when bacterial DNA is randomly incorporated w/ viral DNA; caused by virulent phages; only host DNA is transferred

Answer 51

Generalized transduction

Question 52

``` When bacterial DNA is incorporated along w/ adjacent viral DNA; caused by temperate phages; viral and host genes are transferred ```

Answer 52

Specialized transduction

Question 53

In conjugation, DNA is transferred directly by cell-to-cell contact through the donor’s sex pilus.

Answer 53

Conjugation

Question 54

Plasmids are most frequently transferred by conjugation. This is mediated by a

Answer 54

fertility or F factor/self-transmissibl e plasmid.

Question 55

contain genes conferring drug resistance

Answer 55

R factors

Question 56

fertility and resistance | plasmids

Answer 56

F and R plasmids

Question 57

``` Transposition is the process by which “jumping genes” excise from one genomic location and insert into another. ```

Answer 57

Transposition

Question 58

) can insert themselves into a donor chromosome w/o having DNA homology.

Answer 58

Transposons and insertion | sequences (IS)