Microbio Quiz 3

Front 1

Ribosomes

Back 1

complex structures composed of protein and ribonucleic acid. Site of protein syntheses

Front 2

Cytoplasmic ribosomes

Back 2

the cytoplasmic matrix is often packed with ribosomes that synthesize proteins destined to stay in the cell

Front 3

plasma membrane ribosomes

Back 3

plasma membrane ribosomes make proteins for transport outside the cell

Front 4

How is the shape of each protein determined?

Back 4

the shape of each protein is determined by its amino acid sequence.

Front 5

Molecular chaperones

Back 5

aid the polypeptide in folding to its proper shape

Front 6

Svedberg Unit

Back 6

(S) a measure of sedimentation velocity in an ultracentrifuge. The faster a particle travels when centrifuged, the greater its S value or sedimentation coefficient.

Front 7

S value or sedimentation coefficient is a function of a particles...

Back 7

molecular weight, volume, and shape.
*Heavier particles typically have larger S numbers and sediment faster

Front 8

Eukaryotic cells vs Prokaryotic cells

Back 8

Eukaryotic Cells have two or more chromosomes contained within a membrane - delimited organelle called the nucleaus.
Prokaryotic cells lack a membrane-delimited nucleus

Front 9

Nucleiod

Back 9

an irregularly shaped region found in prokaryotic cells that contains the prokaryotic chromosomes.

Front 10

Prokaryotic Chromosomes

Back 10

Usually contain a single circle of double-stranded DNA molecule as their genetic material. However some have a linear DNA chromosome.

Front 11

Prokaryotes with more than one chromosome....

Back 11

Vibrio Cholerae (cholera) and Borrelia burgdorferi (lyme disease)

Front 12

Unlike the eukaryotes and some Archaea.....

Back 12

Bacteria do not use histone proteins to package their DNA

Front 13

Planctomycetes

Back 13

a phylum of bacteria that has a membrane-bound DNA-containing region present

Front 14

Gemata obscuriglobulus

Back 14

has a nuceoid that is found in the nuclear body which is enclosed by a double membrane called the nuclear body envelope

Front 15

Plasmids

Back 15

extrachromosomal DNA molecules found in prokaryotes. double stranded DNA molecules that can exist independently of the chromosome. most plasmids are circular.

Front 16

Borrelia burgdorferi (talkin' bout plasmids)

Back 16

numerous different plasmids have been identified within single species;
this one has 12 linear plasmids and 9 circular plasmids.

Front 17

Linear plasmids

Back 17

have special structures or sequences at their ends that prevent their degredation and permit their replication.

Front 18

Episomes

Back 18

plasmids that have integrated into the chromosome and thus are replicated with the chromosome.

Front 19

Curing

Back 19

The loss of a plasmid due to unequal dividing. Can occur spontaneously or be induced by treatments that inhibit plasmid replication but not host cell production.

Front 20

Curing treatments involve using..

Back 20

Curing treatments involve using acridine mutagens, UV and ionizing radiation, thymine starvation, antibiotics, and growth above optimum temperatures.

Front 21

Types of Plasmids

Back 21

Fertility Factor(F), Resistance Factors (R), Col plasmids, Virulence, Metabolic

Front 22

Fertility Factor (F)

Back 22

is a conjugative plasmid. F-factor plasmid possesses genes that direct the formation of sex pili that attach an F+ cell to F- cell. Also have several segments called insertion sequences that enable the F plasmid to integrate into the host cell chromosome. Thus, the F factor is an episome.

Front 23

F+ Cell

Back 23

contains the F plasmid

Front 24

F- Cell

Back 24

lacks the F plasmid

Front 25

Resistance Factors (R factors, R Plasmids)

Back 25

are able to confer antibiotic resistance on cells that contain them. R Factors typically have genese that code for enzymes capable of destroying or modifying antibiotics.

Front 26

R plasmid R100

Back 26

ound in E. coli, shingella, and salmonella, and Preus, causes resistance to strptomycin, chloramphenicol, tetracycline, and mercury.

Front 27

Col plasmids

Back 27

possess genes for the synthesis of bacteriocins known as colicins that are directed against E.coli.

Front 28

Bacteriocins

Back 28

bacterial proteins that destroy other bacteria

Front 29

Col plasmid ColE1

Back 29

found in E.coli. Responsible for the production of ColicinE1

Front 30

Cloacins

Back 30

kill Enterobacter species

Front 31

Col plasmid CloDF13

Back 31

found in Enterobacter cloacai is responsible for the production of cloacin DF13, a bacteriocin that kills Enterobacter cloacae

Front 32

Why are bacteriocin-producing strains not sensitive to the actions of their own bacteriocins?

Back 32

The reason for such immunity is that along with bacteriocins, producing strains make proteins that counteract their. Often synthetic and immunity genes are on the same operon, which allows coordinate regulation of their expression.

Losing te immunity genes makes bacteriocin-producing strains sensitve to the actions of their own proteins.

Front 33

Virulence plasmids

Back 33

encode factors that make their hosts more pathogenic

Front 34

enterotoxigenic strands of E.coli

Back 34

cause traveler's diarrha because they contain a plasmid that codes for an enterotoxican

Front 35

Metabolic Plasmids

Back 35

carry genes for the enzyme that degrade substances such as aromatic compounds (toluene), sugar, (lactose), etc

Front 36

The TOL plasmid

Back 36

plasmid of pseudomonas aeruginosa codes for an enzyme that degrades toluene

Front 37

sym plasmid

Back 37

plasmid of Rhizobium carries genes that induce nodule formation in leguemes so that nitrogen fixation can take place.

Front 38

gram positive cell walls

Back 38

walls consists essentially of a peptidoglycan layer. 20-80 nm thick

Front 39

gram negative cell walls

Back 39

consists of an outer membrane and a peptidoglycan layer
2-7 nm thick covered by outer membrane 7- 8 nm thick

Front 40

Thicker peptidoglycan

Back 40

because of the thicker peptidoglycan layer, the walls of gram positive bacteria are more resistant to osmotic pressure than those of gram-negative bacteria

Front 41

Cell envelope

Back 41

everything from the plasma membrane outward. Includes the plasma membrane, cell wall, and other structures like capsules

Front 42

Peptidoglycan (murein)

Back 42

an enormous meshlike polymer composed of many identicle subunits

Front 43

A subunit of the peptidoglycan polymer contains two sugar derivatives,....

Back 43

N-acetylglucosamine (NAG) and N-acetylemuramic acid (NAM) and several different amino acides

Front 44

Three amino acids not found in proteins

Back 44

D- Glutamic acid, D - alanine, and meso-diaminopimelic acid.

Front 45

D - amino acids...

Back 45

protect against degeneration by most peptidases because these peptidases only recognize L-amino acids.

Front 46

The backbone of a peptidoglycan

Back 46

composed of alternating NAG and NAM

Front 47

peptigoglycans....

Back 47

joined by cross-links between peptides of adjacent strands. strand is helical, and peptides extend out from the backbone at right angels to each other

Front 48

A peptide of four alternating D- and L- amino acids is connected to ...

Back 48

the carboxyl group of NAM.

Front 49

In E.coli, one of the amino acids of the tetrapeptide is always a

Back 49

diamino acid

Front 50

meso-diaminopimelic acid (DAP)

Back 50

the diaminio acid found in gram negative bacteria like E-coli

Front 51

L-Lysine

Back 51

the tetrapeptide diamino acid found in gram positive bacteria like Staphyloccus aureus

Front 52

In gram negative bacteria like E.coli, the carboxyl group of the terminal alanin is cross-linked directly to the amino group of DAP

Back 52

In gram-positive bacteria like Staphyloccus aureua, peptide interbridges (5 glycine residues) may be used to crosslink the terminal alanine to lysine

Front 53

sacculus

Back 53

relatively porous, elastic and somewhat stretchable sacs. Example of Bacillus Megaterium.