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Oxymyoglobin
Gives very bright red color to meat
TERM 2
Metmyoglobin
DEFINITION 2
Metmyoglobin is the oxidised form of the oxygen-carrying
protein myoglobin. Gives brown color to meat
TERM 3
Spoilage occurs when the bacterial population
reaches ______.
DEFINITION 3
10^7 or 10^8/g or cm^
TERM 4
What makes spoiled meat appear
'slimy'?
DEFINITION 4
secretion of extracellular polysaccharides by bacteria
TERM 5
Glycolysis
DEFINITION 5
Glycolysis (from glycose, an older term for glucose + -lysis
degradation) is the metabolic pathway that converts glucose,
C6H12O6, into pyruvate, CH3COCOO + H+.
Glycolysis of muscle occurs until the ph
reaches ____.
5.6 to 5.
TERM 7
Cladosporium
DEFINITION 7
produces "Black spot" in meat
TERM 8
Thamindium elegans
DEFINITION 8
produces a condition called "whiskers" in meat
TERM 9
Putrefaction
DEFINITION 9
anaerobic catabolism of proteins which results in noxious
odors; caused by Clostridium in meat
TERM 10
"Bone Taint"
DEFINITION 10
caused by Clostridium or Streptococci. Results in souring
around bones in meat.
"Soft Rot"
casued by Erwina caratovora (psychotroph) in carrots
TERM 17
Grey mold rot
DEFINITION 17
occurs in strawberries caused by Botrytis
TERM 18
Water rot
DEFINITION 18
common rot in tomatoes caused b Grotrichum
TERM 19
Blue Mold Rot
DEFINITION 19
occurs in fuits caused by Penicillium expansum
TERM 20
Causes unclean flavors in Milk
DEFINITION 20
coliforms (e.coli)
Causes Malty flavor in milk
Lactococcus lactis
TERM 22
Causes Fruity flavor in milk
DEFINITION 22
Pseudomonas fragi
TERM 23
causes rancid flavor in milk
DEFINITION 23
pseudomonas
TERM 24
Causes souring of milk
DEFINITION 24
Thermoduric lactic acid bacteria
TERM 25
Foodborne
infection
DEFINITION 25
caused by ingestion of viable cells of a pathogen examples:
E.coli O157:H7 Salmonella enteritidis
Name 3 groups of antigens in serotyping and
state where they are located.
1. "O" or somatic antigen; polysaccharide outer cell
membrane 2. "H"; flagellum 3. "K"; Capsule
TERM 32
What are three hypothesis of epidemiology of
E.coli O157:H7?
DEFINITION 32
1. random mutation of a gene in normal e.coli 2. Obtained
virulence genes from pathogens through conjunction 3.
Genome exchange from one bacteria to the other.
TERM 33
What is the principal reservoir host of E.coli
O157:H7?
DEFINITION 33
The Recto-anal junction in cattle
TERM 34
Virulence factor
DEFINITION 34
ability of bacteria to produce disease
TERM 35
Infectious dose;
DEFINITION 35
min. dose needed to produce disease
what is the infectious dose of e.coli O157:H7?
10-100 cells
TERM 37
Verotoxins
DEFINITION 37
toxins produced by e.coli O157:H7; cause death of vero-cells
(kidney cells found in African monkey) Two types: VT1 and
VT
TERM 38
Name three virulence factors of E.coli
O157:H
DEFINITION 38
1. low infectious dose 2. acid tolerance (survives in G.I) 3.
Produces verotoxins
TERM 39
Verotoxin subunit A
DEFINITION 39
acts at ribosomal level and inhibits protein synthesis
TERM 40
Verotoxin subunit B
DEFINITION 40
Toxin which binds to Gb3 receptors in the kidney cortex and
endothelial cell so blood vessels
Thrombocytopenia
Thrombocytopenia (or -paenia, or thrombopenia in short ) is
the presence of relatively few platelets in blood; associated
with Thrombotic thromoctopenic purpura
TERM 47
Why is it impossible for cattle to fall sick with
E.coli O157:H7 illnesses?
DEFINITION 47
Do not have the GB3 Receptor
TERM 48
What are two contradictions for the treatment
of E.coli? why?
DEFINITION 48
1. antibiotics; lyse the bacteria and induce the release of
more toxin to bind to the receptor 2. Peptobismal (antacid);
slow peristalsis so it will linger longer in the G.I tract *
dialysis and fluids are the recommended treatment
TERM 49
Pathogenic Vs. Normal E.coli
DEFINITION 49
Normal: 1. Appear pink 2. Flourescent in UV light Pathogenic:
1. colorless because Do not ferment sorbital 2. Do not
flouresce in UV light because do not produce B-glucuronidase
because cannot hydrolyze MUG 3. Do not grow well at 44-45C
TERM 50
MUG
DEFINITION 50
4-methyl umbelliferyl D-glucuronide Chemical substrate
which can be broken to priduce B-glucuronidase
Sorbital Mac-Conkey
Agar
cultural method of detecting E.coli O157:H7 verses Normal
E.coli. Contains MUG
TERM 52
what is the most common antibacterial
treatment to decontaminate carcasses in
slaughter houses against E.coli?
DEFINITION 52
Hot water spray washing
TERM 53
What temperature is recommended to cook
ground beef to? Why is color a bad indicator?
DEFINITION 53
71.1C or 160F meat can prematurely brown (metmyoglobin)
TERM 54
2 most common foodborne pathogens in the
U.S
DEFINITION 54
1. Salmonella Enteritidis (in chicken and egg) 2. Salmonella
Typhimurium (In beef pork and milk)
TERM 55
Transovarian transmission
DEFINITION 55
migration from intestine of chicken to egg before the egg is
spawned. Means of contaminating intact eggs by S.
Enteritidis
Vibrio Anguillarium
bacterium from which plasmid jumped to infect S.
Typhimurium
TERM 62
Listeria Monocytogenes
DEFINITION 62
psychotropic foodborne pathogen Gram + causes listeriosis
which has a mortality rate of 25%
TERM 63
What is a high risk food for Listeria
Monocytogenes?
DEFINITION 63
Ready to eat pre-cooked foods because it is a bad competitor
TERM 64
Biofilm
DEFINITION 64
A biofilm is an aggregate of microorganisms in which cells
adhere to each other and/or to a surface.
TERM 65
Quorum
sensory
DEFINITION 65
means of bacteria communicating with eachother in a biofilm
Planktonic cells
immature cells during biofilm formation
TERM 67
Hepatocytes
DEFINITION 67
A Hepatocyte is a cell of the main tissue of the liver. Site of
replication of LM
TERM 68
L. Monocytogenes
symptoms
DEFINITION 68
Flu-like symptoms, Meningitis, meningeoencephalitis and
spontaneous abortion in women
TERM 69
Virulence factors of L. Mono.
DEFINITION 69
1. Listeriolsin O; causes b-hemolysis 2. Internalin; helps enter
non-phagocytic cells
TERM 70
Shigella groups
DEFINITION 70
1. S. dysenteriae 2. S. flexneri 3. S. boydii 4. S. Sonnei
Cecum
The cecum or caecum (from the Latin meaning blind) is a
pouch, connecting the ileum with the ascending colon of the
large intestine. C. jejuni colonizes beneath these mucous
layers and uses L. fucose as a source of energy
TERM 77
Guillain-Barre Syndrome
DEFINITION 77
characterized by acute neuromuscular paralysis caused by C.
jejuni
TERM 78
Virulence factors of C. Jejuni
DEFINITION 78
1. adhesins; help attach to host *2. mucus colonization;
provides energy source 3. Heat stable toxin *4. Cytolethal
distending toxin ; screws energy cell shape 5. resistance to
antibiotics
TERM 79
How do you detect C. jejuni?
DEFINITION 79
Selective agar; contains selective antibiotics and sheep blood
(iron) gaseous environment and 42C incubation temp
TERM 80
Staphylococcus aureus
DEFINITION 80
causes foodborne intoxication by producing heat stable
enterotoxins. Very short incubation period 2-6 hours pre-
Cooked high protein foods are major concern
2 psychotropic foodborne pathogens
Listeria monocytogenes Yersinia enterocolitica
TERM 82
Invasin
DEFINITION 82
Virulence factor of Y. enterocolitica which invades intestinal
cells
TERM 83
Yernisina
Enterocolitica
DEFINITION 83
swine is principal resevoir
TERM 84
Ail
DEFINITION 84
protein virulence factor produced by YE which attaches to
intestinal wall to overcome peristalsis motion
TERM 85
Virulence Factors of YE
DEFINITION 85
Invasin Ail Yop heat stable enterotoxin sideospore
Why can't TDH lyse horse
RBC's?
horse blood lacks the ganglioside GT1 and GD1a receptors
TERM 92
What is used to detect V.
parahemolyticus?
DEFINITION 92
Kanagawa reaction in wagatsuma's agar (growth agar w/ 5%
human blood and 3-5% salt) -lysis of RBCs occurs in the agar
TERM 93
Most serious vibrio associated with most
seafood deaths
DEFINITION 93
Vibrio Vulnificus
TERM 94
Symptoms of V.
Vulnificus
DEFINITION 94
GI, hypotension, septicemia, necrotizing lesion on extremities
TERM 95
Why are people with chronic liver of blood
disorders or liver cirrhosis especially
susceptible to V. Vulnificus?
DEFINITION 95
Have increased Iron in the liver and blood
Main symptom of Cholera
Rice water diarrhea
TERM 97
Mucinase
DEFINITION 97
produces mucinase enzyme that breaks down the mucous
layer, causes rice water diarrhea -virulence factor of V.
cholerae
TERM 98
Name three virulence factors of V. cholerae
DEFINITION 98
1. OmpU 2. Mucinase 3. Cholera toxin
TERM 99
name 2 opportunistic pathogens
DEFINITION 99
1. aeromas hydrophilia 2. Plesmiomonas shigelloides
TERM 100
True of false; some strains of A. hydrophilia
are psychrotropic
DEFINITION 100
True!
