Bacterial Cell Structure And Antibiotic Targets

Front 1

short, thin, hairlike, proteinaceous appendages; mediate attachment to surfaces

Back 1

fimbria

Front 2

similar to fimbriae except longer, thicker, and less numerous , required for mating

Back 2

sex pilus

Front 3

orderly arrangement of bacteria into groups

Back 3

Classification

Front 4

practical use of classification criteria to distinguish certain bacteria from others

Back 4

identification

Front 5

means by which characteristics of a species are defined and communicated among microbiologists

Back 5

nomenclature (naming)

Front 6

3 major categories of bacteria based on structures from cytoplasmic membrane to cell surface

Back 6

Gram positive, Gram negative, Acid-Fast

Front 7

Which type of bacteria have the thickest cell envelopes?

Back 7

Gram positive

Front 8

H-antigens

Back 8

prokaryotic flagella responsible for bacterial motility

Front 9

Functions of Bacterial Capsules

Back 9

Increases resistance to phagocytosis
Structure for cell attachment-tissue tropism
Potential source of growth substrates

Front 10

LPS is unique to what type of bacteria?

Back 10

Gram negative

Front 11

teichoic acids are unique to what type of bacteria?

Back 11

Gram positive

Front 12

Outer membrane of gram neg bacteria contains

Back 12

LPS, porins, lipoprotein (small molecules can move easily through porins)

Front 13

Inner/Cytoplasmic membrane of gram neg bacteria characteristics

Back 13

Composed of phospholipids, not permeable to ions, contain nutrient transporters, electron transport chain, and biosynthetic enzymes for peptidoglycan and LPS biosynthesis

Front 14

What is the "active" component of LPS?

Back 14

Lipid A

Front 15

Components of LPS?

Back 15

O-antigen (variable), polysachharides, Lipid A(invariable)

Front 16

Structure of peptidoglycans

Back 16

Two alternating sugars for the backbone: N-acetylglucosamine, N-acetylmuramic acid

Front 17

The gram stain procedure: is it useful for acid-fast bacteria?

Back 17

No

Front 18

Stages of peptidoglycan biosynthesis (3)

Back 18

Stage 1: Precursors synthesized in cytoplasm
Stage 2: Precursors transported across the cytoplasmic membrane bound to lipid carrier
Stage 3: Precursors are polymerized and cross-linked to form a macromolecular sheet

Front 19

What antibiotics inhibit stage 1 of peptidoglycan synthesis?

Back 19

Fosfomycin and Cycloserine

Front 20

PEP analog, inhibits UDP-muramic acid biosynthesis

Back 20

Fosfomycin

Front 21

Analog of D-alanine, competiviely inhibits conversion of L Alanine to D Alanine and synthesis of D Alanine D Alanine.

Back 21

Cycloserine

Front 22

During what stage is N-acetylmuramic acid linked to N-acetylglucosamine transported across the cytoplasmic membrane linked to lipid carrier?

Back 22

Stage 2

Front 23

Mech of action of vancomycin and ristocetin

Back 23

Bind to D-Alanine-D-Alanine structure and prevent transfer to acceptor. (Inhibit Stage 2)

Front 24

Mech of action of bacitracin

Back 24

Inhibits dephosphorylation of lipid carrier by binding to pyrophosphate (Inhibit Stage 2)

Front 25

During what stage is cross-linking of parallel polymers of N-acetylmuramic acid and N-acetylglucosamine ?

Back 25

Stage 3

Front 26

What happens to cross link N-acetylmuramic acid and N-acetylglucosamine?

Back 26

Terminal D-alanine is cleaved during transpeptidation which links the third amino acid to the remaining D alanine

Front 27

Mech of action of penicillin and cephalosporin antibiotics

Back 27

Inhibits Step 3 (cross linking)

Front 28

What is the reactive site of penicillin? Significance of this?

Back 28

peptide bond of beta lactam ring. It resembles the conformation of the transition state of alanine linkup in transpeptidation reaction

Front 29

What part of LPS provides protection from host defenses ?

Back 29

O antigen

Front 30

What part of LPS contributes to negative charge on cell surface?

Back 30

core polysaccharide

Front 31

What part of LPS helps stabilize outer membrane structure?

Back 31

lipid A

Front 32

What part of LPS can act as an endotoxin?

Back 32

lipid A

Front 33

In the gram reaction, what kind of bacteria retains crystal violet dye and stains dark purple?

Back 33

Gram-positive

Front 34

In the gram reaction, what kind of bacteria can be decolorized to accept counterstain/safranin and stain red?

Back 34

Gram-neg

Front 35

Peptidoglycan layer thickest in _____

Back 35

gram-pos

Front 36

highly toxic part of acid-fast bacteria cell envelope

Back 36

mycolic acid

Front 37

Class of antibiotics that inhibits bacterial DNA gyrase

Back 37

Quinolones

Front 38

Antibiotic that inhibits transcription by binding to beta subunit of bacterial RNA polymerase

Back 38

rifampin

Front 39

Class of antibiotics that inhibit protein synthesis at the 30s ribosomal subunit

Back 39

Tetracyclines and aminoglycosides

Front 40

Antibiotics that inhibit the transpeptidase reaction by binding to 50S ribosomal subunit.

Back 40

Chloramphenical, erythromycin, and clindamycin

Front 41

Inhibits bacterial dihydrofolate reductase

Back 41

Trimethoprin

Front 42

What part of the bacterial cell envelope prevents removal of red dye/fuscin with acid?

Back 42

Cell wall bound mycolic acid/lipid

Front 43

T/F Bacteria synthesis tetrahydrofolate (THF) from scratch while humans must intake dihydrofolic acid

Back 43

t

Front 44

T/F Sulfa and trimethoprin have synergistic effects in that they inhibit the THF pathway in two places

Back 44

T

Front 45

what drugs inhibit folic acid biosynthesis by acting as competitive inhibitors of P-aminobenzoic acid?

Back 45

Sulfa

Front 46

What drugs inhibit bacterial (but not mammalian) dihydrofolate reductase?

Back 46

Trimethoprin

Front 47

Binds D-ala-D-ala and inhibits transfer of growing cell wall polymer

Back 47

Vancomycin

Front 48

Quinolones and Nalidixic acid inhibit ____________

Back 48

DNA replication (DNA gyrase)

Front 49

Rifampin inhibits __________

Back 49

DNA-dept RNA polymerase

Front 50

Erythromycin, Chloramphenicol, and Clindamycin inhibit ______________

Back 50

Protein synthesis through the 50S subunit

Front 51

Tetracycline, -mycins, and Amikacin inhibit ___________

Back 51

Protein synthesis through the 30S subunit

Front 52

Polymixins disrupt __________

Back 52

the structure of the bacterial cell membrane by interacting with its phospholipids.

Front 53

Trimethoprim and Sulfonamids inhibit ___________

Back 53

folic acid metabolism

Front 54

Cycloserine, vancomycin, bacitracin, fosfomycin, penicillin, cephalosporins, monobactams, carbapenems inhibit __________

Back 54

cell wall synthesis

Front 55

LPS is also know as _____

Back 55

endotoxin

Front 56

physical property of some bacteria referring to their resistance to decolorization by acids during staining procedures.

Back 56

acid fast

Front 57

Mycolic acids found in genera __________________

Back 57

Mycobacteria and Nocardia

Front 58

What is "cord factor?"

Back 58

Toxic, ether-extractable glycolipid in mycobacterium tuberculosis' cell envelopes. Composed of disaccharide threhalose in ester linkage to mycolic acids. Acid fast bacteria also contain cell wall bound mycolic acids

Front 59

Two genera of bacteria that sporulate

Back 59

Bacillus and Clostridium

Front 60

Characteristics of bacterial spores

Back 60

Highly resistant to heat, chemicals, UV light, and dessication

Front 61

What compound imparts the indestructibility of bacterial spores?

Back 61

calcium dipicolinic acid