Module 2

Question 1

LAB Classification

Answer 1

Firmicutes –> Bacilli –> Lactobacillales

Question 2

General LAB Description

Answer 2

Acid tolerant, non-spore formers, Non-respiring, Cocci or rods

Question 3

LAB Growth is

Answer 3

Fastidious

Question 4

Metabolism of LAB

Answer 4

Strict fermentation with lactic acid as the major end product

Question 5

Phenotypic classification

Answer 5

Type of fermentation; does not match rRNA phylogeny

Question 6

LAB Strains

Answer 6

Enterococcous, Lactococcus, Lactobacacillus, Streptococcus, Vagococcus

Question 7

Group D

Answer 7

Enterococci

Question 8

Group N

Answer 8

Lactococcus and Vagococcus

Question 9

Streptococcus Groups

Answer 9

Oral and Pyogenic

Question 10

Most widely used in cheese fermentation

Answer 10

Lactococcus lactis

Question 11

Probiotics and silage starter

Answer 11

E. faecium and faecalis

Question 12

Wide span of mol G+C

Answer 12

Lactobacillus (32-53%)

Question 13

Group 1 obligatory homofermentative

Answer 13

Only produce lactic acid (no CO2)

Question 14

Group II facultatively Heterofermentative

Answer 14

Only lactic acid under certain conditions but can ferment pentose

Question 15

Present in Homo

Answer 15

FDP Aldolase

Question 16

Present in FH

Answer 16

Pentose fermentation, CO2 from gluconate, FDP aldolase, PK

Question 17

Present in OH

Answer 17

Pentose ferm, CO2 from glucose and gluconase, PK

Question 18

Absent from OH

Answer 18

FDP aldolase

Question 19

FDP Aldolase conversion

Answer 19

Fructose 1,6, P –> Dihydroxyacetone-p + G3P

Question 20

Lactate Dehydrogenase (LDH)

Answer 20

G3P –> Pyruvate then –> Lactate

Question 21

Homofermentation enzymes

Answer 21

FDP aldolase +LDH

Question 22

Products of Homofermentation

Answer 22

2 ATP + 2 Lactate

Question 23

Mixed acid fermentation

Answer 23

Alternative pyruvate end products

Question 24

Mixed acid fermentation invovles

Answer 24

FDP aldolase + LDH or PFL

Question 25

Pyruvate formate lyase (PFL)

Answer 25

Pyruvate --> acetyl CoA

Question 26

Acetyl CoA becomes

Answer 26

Acetyl-P and Acetylaldehyde

Question 27

Acetyl-P and Acetyl-aldehyde become

Answer 27

Acetate and Ethanol

Question 28

Products of mixed acid fermentation

Answer 28

3 ATP + 2 Formate + 1 Ethanol + 1 Acetate

Question 29

Key enzymes of FH

Answer 29

FDP Aldolase + PFL

Question 30

All enzymes FH

Answer 30

FDP aldolase + PFL + LDH

Question 31

CO2 Step

Answer 31

Glucose --> Ribulose 5 P

Question 32

Phosphoketolase

Answer 32

Xylulose-5-P --> G3P + Acetyl-P

Question 33

Acetyl-P in PPP

Answer 33

Acetate and Acetylaldehyde

Question 34

PPP Acetylaldehyde

Answer 34

Ethonol

Question 35

Heterolactic Fermetnation of glucose is

Answer 35

Pentose Phosphate Pathway

Question 36

End Products of PPP

Answer 36

2 ATP + 2 CO2 + 1 Lactate + 1 Acetate

Question 37

Key enzymes of PPP

Answer 37

PK + LDH + (NADH Oxidase)

Question 38

LAB Proteolytic System

Answer 38

Cell wall/membrane Proteinase (at least) + aa, di, tri-peptide, oligopeptide transport system with peptidases

Question 39

Proteinase

Answer 39

Breaks down proteins in CW so smaller fragements can go through the membrane

Question 40

Peptidases

Answer 40

Oligopeptides to Di, tri, aa