enteric bacteria
Download
Skip this Video
Download Presentation
Enteric Bacteria

Loading in 2 Seconds...

play fullscreen
1 / 21

Enteric Bacteria - PowerPoint PPT Presentation


  • 484 Views
  • Uploaded on

Enterobacteriaceae Gram negative bacilli ferment glucose oxidase (-). Enteric Bacteria. Escherichia Enterobacter Klebsiella Serratia Citrobacter. Proteus (usually nonpathogenic) Shigella Salmonella. Normal Flora vs. Pathogens. COLIFORMS. NON-COLIFORMS. Lactose Fermentation?. yes.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Enteric Bacteria' - livia


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
normal flora vs pathogens
Escherichia

Enterobacter

Klebsiella

Serratia

Citrobacter

Proteus (usually nonpathogenic)

Shigella

Salmonella

Normal Flora vs. Pathogens

COLIFORMS

NON-COLIFORMS

obligate enteric pathogens

Shigella dysenteriae

Salmonella typhimurium

http://www.mpg.de/news02/news0209.htm

http://www.co.boulder.co.us/health/hpe/FactSheets/salmonella.htm

Obligate Enteric Pathogens
escherichia coli o157 h7

http://www.quarks.de/milch/06.htm

Escherichia coli O157:H7

http://www.jfha.or.jp/saikin/shashin/o157.html

eosin methylene blue emb agar
Eosin Methylene Blue (EMB) Agar

E. coli

http://www.cat.cc.md.us/courses/bio141/labmanua/lab3/embeacolony.html

E. aerogenes

S. Typhimurium

P. aeruginosa

slide7

Electrons from carbos(or other food source)

Electron carriers

NO3-, SO42-,CO2

O2(Aerobic respiration)

Pyruvic acid

(Anaerobic respiration)

(Fermentation)

Black, J.G (2002) Microbiology: Principles and Explorations 5th Ed. Fig. 5.21

fermentation pathways
Fermentation Pathways

Glucose(or other sugar)

Butyric acid, butanol,isopropyl alcohol,acetone & CO2

Propionic acid,acetic acid,& CO2

Pyruvic acid

Butyric-butylicfermentation

Propionic fermentation

Black, J.G (2002) Microbiology: Principles and Explorations 5th Ed. Fig. 5.11

Butanediol& CO2

Ethyl alcohol& CO2

Acetic aid,succinic acid,ethyl alcohol,

CO2 & H2

Butanediolfermentation

Lactic acid

Alcoholic fermentation

Mixed-acidfermentation

Homolactic acidfermentation

sugar fermentation
Sugar Fermentation
  • Melibiose
  • Amygdalin
  • Arabinose
  • Sorbitol
  • Rhamnose
  • Sucrose
  • Glucose
  • Mannitol
  • Inositol

Must use additional reagents to GLU to see result

catabolic enzymes
Catabolic Enzymes
  • Beta galactosidase
  • Arginine dehydrogenase
  • Lysine decarboxylase
  • Ornithine decarboxylase
citrate utilization
Citrate Utilization

blue indicates citrate utilization and alkaline by-products

sulfur reduction
Sulfur Reduction

CH2

SH

CH3

cysteine desulfurase

H2S

COOH

+

CH

H2N

CH

COOH

H2N

(hydrogen sulfide)

(alanine)

(cysteine + sodium thiosulfate)

Fe++ (in medium)

FeS

(iron sulfide)

(black ppt)

nitrogen fixing

H2N

NH2

urease

2 NH3

+

CO2

C

(ammonia)

O

(urea)

Nitrogen Fixing
tryptophan indole reaction

H2O +

H2N

Tryptophan deaminase

(indole)

COOH

CH2

CH

N

(tryptophan)

N

+

NH3

(ammonia)

+

CH3

C = O

(pyruvic acid)

COOH

Tryptophan - Indole Reaction

Must add Kovac’s reagent to see result

acetoin reaction
Acetoin Reaction

Must add KOH and α-naphthol to see result

gelatinase s
Gelatinase(s)
  • Large group of proteolytic enzymes
  • Degrade collagen
  • Metalloproteases
  • Virulence factors
api test sample prep
API Test : Sample Prep
  • Pick ONE SINGLE colony (no agar)
  • Emulsify colony by pipetting up and down in small amount of liquid
inoculating api test strips
Inoculating API Test Strips

Overlay with mineral oil:

  • ADH, LDC, ODC, H2S, & URE
  • Fill tubules & cupules:
  • CIT, VP & GEL
  • (see pg. 223 in lab manual)
reading api test strips
Reading API Test Strips
  • Use chart on pp. 225-8 in manual to determine results
  • Record + or – results for each test
  • Add + results in oval below tests
  • Record 7-digit code and look up ID
ad