LESSON 5.2 [A] Flashcards
is a class of several medically, ecologically and scientifically important groups of bacteria such as Enterobacteriacease, Vibrionaceae, and Pseuomonadaceae
Gammaproteobacteria
Largest and most diverse class of proteobacteria; more than 1500 charaterized species among its 15 orders; include many well known human pathogens, developed quickly in laboratory media and found various habitats
Gammaproteobacteria
homogenous phylogenetic group within gamma proteobacteria; facultative aerobic, gram negative, non sporulating rods
Enterobacterales (Enteric bacteria)
found in the intsestinal tract of humans and warm-blooded animals; plays a potential nutrional role by synthesizing vitamins, particularly vitamin K
E.coli
wild type strains exhibit minimal growth-factor requirements; can grow on a wide variety of carbon and energy sources
E. coli
major cause of urinary tract infections in women; can cause severe foodborne diseases; infection occurs via consumption of contaminated foods or water
Pathogenecity of E.coli
what is the relationship between salmonella and escherichia ?
closely related; salmonella are predominantly pathogenic, whereas Escherichia species have diverse roles.
Key genera in enterobacteriales
Enterobacter, Escherichia, Klebsiella, Proteus, Salmonella, Serratia, Shigella
species that are typically pathogenic to humans and warm blooded animals; eg. raw egg; became famous in peanut butter skippy; common diseasess are thypoid fever and gastroenteritis in humans
Salmonella
Shigella is genetically closely related to Escherichia, _______ in similarity; show _______ between the two genes
80%, Horizontal gene transfer
species that are typically pathogenic to humans causing severe gastroenteritis known as bacillary dysentery
SHigella
one species of shigella that are transmitted through cpntaminated food and water, produces endotoxin, and neurotoxin leading to acute gastrointestinal dstress; majority are acquired from uncooked food
Shigella dysenteriae
difference bteween E. coli and Salmonella in colony morphology
- E.coli has red pigmentation; lactose negative like colonies with gas formation from glucose
- Salmonella is lactose negative without gas formation
Highly motile cells that produce urease enzyme, meaning urease positive; distant relationship to e.coli
Proteus
colony morphology of proteus
edge cells are more rapidly motile than central ccells, its shape is like scales of fish because they are motile
The genera under Enterobacteriales undergo __________
butaneidol fermentation
Butanediol fermenters are more ______ than to mixed-acid fermenters
closely related to each other
a butanediol fermenter that is commonly found in watr, sewage, and the intestinal tract of warmblooded animals; occasionally causes urinary tract infections
enterobacter aerogenes
it commonly found in soild and water; occasionally causes pneumonia in humans; nosocomial and opportunistic causing harm to humans
Klebsiella
it produces pigment called red pyrrole or also known as prooigiosins;commonly found in watr, soil, gut of insects and vertebrates and occasionally in human intestines
Serratia
is a pathogenic bacteria that causes infections in various body sites and contaminates inravenous fluid
Serratia macescens
exclusively chemoorganotrophic with respiratory metabolisms; most are aerobic, oxidase, and catalase positive, with some capable of anaerobic respiration using nitrate; utlize a wide rnge of organic compounds as carbon and energy sources; ubiquiotius in soil and aquatic systems
Pseudomonadales
they are gram-negative, polarly flagellated aerobic rods, capable of using diverse carbon sources; considered within the order Pseudomonadales
Pseudomonads
colny morphology of P. aeruginosa in routine blood agar
gray-white with a yellowish tint through green to red or brown
the pigment production of P. aeurginosa is better visible and more profound on _________
Mueller-Hinton agar
Encapsulated starins of P. aeruginosa usually isolated from patients with pneumonia produce ________
large mucoid colonies.
Pathogenic species of Pseudomonads
P. aeruginosa and P. syringae
opportunistic pathogen associated with urinary and respiratory tract infections in humans; resiatnt to many antibiotics due to R-plamsid; can cause systemic infections particulalry in individuals with extensive skin damage or cystic fibrosis
P. aeruginosa
well known plant-pathogens causing various disease synptoms in host plants; isolted leaves from showing chlorotic lesiosn; In humans P. aeruginosa causes diseases whereas in plants, it is_______
Pseudomonas syringae
what is the genera of pseudomonadales
pseudomonads
genera if vibrionales
aliiivibrio and Vibrio
facultative aerobic rods and curved rods; employ fermentative metabolism; oxidase positive
vibrionales
vibrio species are oxidase______ whereas enteric bacteria are oxidase _______
positive, negative
several species of vibrionales exhibit ______
bioluminescence
Pathogenicity of Vibrionales
- Vibrio cholerae
- Vibrio parahaemolyticus
causes cholera in humans, primarily trasmitted via water; common in developing countries
Vibrio cholerae
major causes off gastroentritis, especially in japan because they frequently eat seafood such as raw fishes; associated with consumption of fish
vibrio parahaemolyticus
when using Thiosulfate citrate bile salts sucrose agar, vibrio cholerae has _______ or margin while vibrio parahemolyticus _________formation
yellow, do not have this
enterobacterales are oxidase-_____ and catalase-_____
oxidase-negative, catalase positive
Metabolic characteristic of Enterobacteriales
- Produce acid from glucose
- Reduce nitrate to nitrite
- Ferment sugars to various end products.
fermentation patterns in enteric bacteria
- mixed acid fermentation
- 2,3 butaneidol fermentation
three significant acids in mixed acid fermentation
- acetic
- lactic
- succinic
products of mixed acid fermentation
ethanol, co2, and h2
main products of 2,3-butanediol fementation
butaneidol, etahnol, co2, and H2
CO2 and H2 Production of mixed acid fermentation
equal amounts of co2 and h2
CO2 and H2 Production of butanediol fermentation
more co2 than h2
genera in butanediol fermentation
Enterobacter, Klebsiella, Erwinia, and Serratia
Genera in Mixed acid fermentation
Escherchia,, Salmonella, Shigella, Citrobacter, Proteus, and Yersinia
