ppt Flashcards
these are simple tests that can identify the bacterium up to a generic level
gram reaction
widely used for the routine staining of bacteria in smears
gram stain
useful for demonstrating dermatophilus congolensis, rickettsiae and borrelia species which stain blue
giemsa stain
especially useful for recognizing campylobacter species, brachyspira species and fusobacterium species which stain red
dilute carbol fuchsin
used for the identification of bacillus anthraic in blood smears
polychrome methylene blue
hot concentrated carbol fuchsin which penetrates mycobacterial cell walls is retained after acid alcohol decoloriation
ziehl-neelsen stain
unlike ziehl neelsen stain, this metjod employs dilute carbol fuchsin with decolorization by acetic acid
modified zhiel neelsen
macConkey may differ in the composition of ___
bile salts or presence of crystal violetu
supports the growth of all members of the eneterobacteriaceae but selectively inhibitory to tother gram negative bacteria
macconkey
allows differentiation of lactose fermenters from non-lactose fermenters
macconkey
this test detects enzyme catalase that converts hydrogen peroxide to water and gaseous oxygen
catalase test
the positive reaction of this test is the effervescence of oxygen gas within few seconds
catalase test
Routinely used as an aid in distinguishing between
staphylococcus from streptococcus
catalase test
in catalase test, which is positive. staphy or strepto
staphy
2 methods of catalase test
- Loopful of bacteria on clean
microscope slide + a drop of
3% hydrogen peroxide - A drop of 3% hydrogen peroxide is added to a colony on the plate and another drop on the area of the agar plate without bacterial growth
this test depends on the presence of cytochrome c oxidase in a
bacterial cell
oxidase test
these are oxidase negative
anaerobes
these bacterai can be used as a positive control organism
pseudomonas aurUGINOSA
the majority of bacteria are motile by means of
flagella
Motility can be temperature –dependent and some bacteria tend to be motile at
ambient temp but not at 37 degree celsius
these can be added in the media to aid the detection of motility
tetrazolium salt
a composite medium for the determination of hydrogen sulphide and indole production and motility
SIM medium
medium used mainly for enterobacteriaceae
SIM medium
this test is used to determine the oxidative or fermentative metabolism of a carbohydrate by
the bacterium
oxidation-fermentation test
The medium is semi- solid and
usually contains glucose and bromothyl blue as
pH indicat
o-f test
- Bacteria that requires atmospheric oxygen for
growth and metabolism are
oxidative
Bacteria that can metabolize glucose under
aerobic or anaerobic conditions are
facultative anaerobes
facultative anaerobes in o-f test is
fermentative
o-f test results
if unreactive, both opena nd sealed tube is green (bordetella)
oxidation- open tube is yellow, sealed tube is green (pseudomonas)
in fermentation, open and sealed tube is both yellow(aeromonas)
in lana test, a swab is impregnated with ____
l-alanine-4-nitroanilide
what is the reslt if the swab in lana test turned yellow
the bacterium is gram negative
medium to indicate hemolysis
blood agar
what does it mean if a viscous gel is forming in a KOH test
it is a gram negative bacteria
the majority of a gram positive bacteria is susceptible to
vancomycin. gram negative are resistant
what are the primary biochemical tests for the identification of bacteria
gram staining
growth or absence of growth on MacConkey
presence or absence of hemolysis on blood agar
catalase test
oxidase test
motility test
SIM medium
KOH test
O-F test
LANA test
susceptibiluty to vancomycin
enzymatic attack on sugar with
acid and gas production (Durham tubes
carbohydrate fermentation test
tested for the ability of the microorganism to use citrate as sole carbon source
citrate utilization test
chiefly used in the differentiation
of Gram-positive rod
citrate utilization test
what bacteria can utilize citrate for growth
aerogenes group
lacks transport system that
would permit the citrate to enter the cell to be use
e coli
ability of an organism to liquefy
or hydrolyze gelatin
gelatin liquefaction
what does gelatin liqeufaction indicates
gelatin loses its gelling properties
and remains a liquid even at low
temperature
- a i d s i n t h e i d e n tifi c a ti o n o f
o r g a n i s m s w i t h i n t h e
Enterobacteriaceae
decarboxylase test
The specific decarboxylase enzyme produced by an organism results in the breakdown of the amino acid concerned and the fermentation of the corresponding amino acid
ornithine-putrescine
lysine-cadaverine
arginine-agmatine
glutamic acid-aminobutyric acid
tryptophan split to indole
indole test
together with VP test, this is useful in
differentiating between coli-aerogenes
group of enteric bacter
methyl red test
-it is a confirmatory test for the
butylene glycol type of fermentation of
bacteria
voges-prokauer test
it detects the presence of acetoin or acetylmethylcarbinol, which is an intermediate in the production of butylene glycol
voges-prokauer test
discuss the nitrate reduction test
nitrate-nitrite-nitrogen gas
-test for the production of the
enzyme urease by bacteri
urease test
-used for the identification of
Proteus organism as well as the
differentiation of other
microorganisms
urease test
Urease breakdown urea to form
ammonia nad co2
-fermentation of sugars, hydrogen sulfide production, gas formation (hydrogen and carbon dioxide)
triple sugar iron
-useful for presumptive identification of
Salmonella
tsi
in tsi, utilization of the ferrous substrate is indicated by
production of black color
the black color in tsi is
hydrogen sulfide
in tsi, if the medium becomes yellow, it means
acid production
alkaline color of the medium in tsi is due to
peptone degradation
in tsi, gas formation will show
cracks, bubbles, and indentation of the medium
a basic medium where non fastidious bacteria grows
nutrient agar
it is suitable for demonstrating colonial morphology and pigment production. also used for viable counting methods
nutrient agar
an enriched medium which supports the growth of most pathogenic bacteria and is used for their primary isolation
blood agar
allows the recognition of haemolysin production
blood agar
allows differentiation of lactose fermenters and non lactose fermenters
macconkey agar
selective enrichment media used for the isolation of salmonellae from samples containing other gram negative enteric organism
selenite broth, rappaport-vassiliadis broth
a blood agar based selective medium used for the inocculation and recognition of streptococci
edwards medium
heat treated blood agar which supplies special growth requirements for the isolation of heamophilus species and for the culture of taylorella equigenitalis
chocolate agar
used for the identifiction of enterobacteriadceae
IMViC testh
what is imvic test
indole
methylene red
voges-prokauer
citrate utilization
