microbiology 1-15

acetamide utilization

To differentiate microorganisms based on their ability to use acetamide as the sole source of carbon.

acylamidase

in acetamide utilization, the bacteria here can produce an enzyme called?

which deaminates acetamide to release ammonia.

ammonia

The production of _____ in acetamide utilization results in an alkaline pH, causing the medium to change color from green to royal blue

blue color
pseudomonas aeruginosa

what is the expected positive result in acetamide utilization?

deamination of acetamide resulting in what positive result?
and what organism is seen

bromothymol blue

pH indicator; green changes to blue when the medium becomes alkaline. can be seen in acetamide utilization

green
Escherichia Coli

what is the expected result if negative in acetamide utilization?

and what org is seen

10g
6.8

in acetamide utilization, how many grams of acetamide is used and what is its pH level

acetate utilization

Differentiate organisms based on ability to use acetate as the sole source of carbon. Generally used to differentiate Shigella spp. from Escherichia coli

sodium acetate

in acetate utilization
Organisms capable of using _______ grow on the medium, resulting in an alkaline pH, turning the indicator from green to blue

blue

ESCHIRICHIA coli

what is the expected positive result in acetate utilization
the positive result is seen when the ph turns alkalinized indicating growth of?

what organism:
what color:

green (non changes)
shigella sonnei

what is the expected negative result in acetate utilization?
what presence of organism is seen?

color:
organism:

L-alanine-7-amido-4-methylcourmarin

This test is used in conjunction with the Gram stain to distinguish aerobic gram-positive rods or coccobacilli that may appear gram-negative or gram-variable.

aminopeptidase

this is enzyme produced by gram negative bacteria during L-alanine-7-amido-4-methylcourmarin

this has the ability oh hydrolyzing the reagent in the disk producing blue fluorescent compound that is visible under long-wave UV light

aerobic gram negative - blue fluorescent
escherichia coli

what is the expected result in L-alanine-7-amido-4-methylcourmarin test when its positive

what type of gram: negative or positve?
what color or outcome:
what specie is seen:

aerobic gram-negative - no fluorescent
staphyloccocus aureus

what is the expected result in L-alanine-7-amido-4-methylcourmarin test when its negative

what type of gram? negative or positive

Bacitracin susceptibility test

This test is used for presumptive identification and differentiation of beta-hemolytic group A streptococci (Streptococcus pyogenes–susceptible) from other beta-hemolytic streptococci. It is also used to distinguish staphylococci species (resistant) from micrococci (susceptible).

staphylococci

in bacitracin susceptibility test, the organism known to be resistant are what specie

micrococci

in bacitracin susceptibility test, the organism known to be susceptible are what specie

streptococcus pyogenes

Differentiate beta-hemolytic Group A Streptococcus from other beta-hemolytic streptococci.

the group a hemolytic patter is what? in bacitracin susceptibility test

bacterial cell wall

Bacitracin is an antibiotic that interferes with what part of bacteria?

streptococcus pyogenes
micrococcus luteus
susceptible

in bacitracin susceptibility test, what is the expected positive result?
susceptible or resistant:
what specie

streptococcus agalactiae
staphylococcus aureus
resistant

in bacitracin susceptibility test, what is the expected negative result?
susceptible or resistant:
what specie

bile esculin test

This test is used for the presumptive identification of enterococci and organisms in the Streptococcus bovis group. The test differentiates enterococci and group D streptococci from non–group D viridans streptococci.

enterococci
streptococcus bovis group
viridans streptococci

This test is used for the presumptive identification of ________and ________ . this also differentiate from non group D which is

in bile esculin test

enterococci
streptococci
gram positive

are inhibited by the bile salts in this medium.
in bile esculin test:

_______ other than some ______ or _____ are inhibited by the bile salts in this medium.

enterococcus faecalis

Organisms capable of growth in the presence of 4% bile and able to hydrolyze esculin to esculetin will demonstrate growth.

Fe13 / ferric ammonium citrate

Reacts with esculetin to produce blackening.

blackening
enterococcus faecalis

what is the expected positive result in bile esculin test
what reaction:
what organism:

no reaction
streptococcus pyogenes
escherichia coli

what is the expected negative result in bile esculin test
what reaction:
what organism:

bile solubility test

This test differentiates Streptococcus pneumoniae (positive; soluble) from alpha-hemolytic streptococci (negative; insoluble).

amidase

in bile solubility test, Lysis depends on the presence of an intracellular autolytic enzyme? WHAT ENZYME

bile salt

_____ lower the surface tension between the bacterial cell membrane and the medium, thus accelerating the organism’s natural autolytic process.

in bile solubility test

streptococcus pneumoniae (bile soluble)
lysed colony

what is the expected positive result in bile solubility test

what happened to the colony:
soluble or insoluble
what org is present:

enterococcus faecalis (bile insoluble)
intact colony

what is the expected negative result in bile solubility test

what happened to the colony:
soluble or insoluble
what org is present:

CAMP TEST

test is used to differentiate group B streptococci (Streptococcus agalactiae–positive) from other streptococcal species. Listeria monocytogenes also produces a POSITIVE REACTION

STREPTOCOCCUS AGALACTIAE
ARROW FORMED (ENHANCED HEMOLYSIS)

IN CAMP TEST, WHAT IS THE EXPECTED POSITIVE RESULT?
WHAT ORGANISM
WHAT DO YOU SEE

no hemolytic enhancementstaphylococcus pyoegenes

in camp test, what is the expected negative result?
what organism is associated?
what appearance will be observed

hemolytic protein

what protein is responsible in camp test that act synegistically with beta lysin of aureus

catalase test

This test differentiates catalase-positive micrococcal and staphylococcal species from catalase-negative streptococcal species.

staphylococcus aureus
copious bubbles

what is the expected positive result in catalase test
what organism
what is observed

staphylococcus pyogenes
no bubbles

in catalase test, what is expected result for negative?

what organism
what apperance is observed

catalase

what enzyme is responsible in catalase test that transform superoxide radicals and hydrogen peroxide into water

cetrimide test

This test is primarily used to isolate and purify Pseudomonas aeruginosa from contaminated specimens.

pseudomonas aeruginosa
yellow-green to blue-green / variation of color in colonies

what is the expected positive result in cetrimide test?

what organism

what is observed

escherichia coli
no color changes

in cetrimide test, what is the expected negative outcome?
what organism
what appearance

cetrimide

toxic substance that inhibits the growth of many bacteria by causing the release of nitrogen and phosphorous, which slows or kills the organism

CITRATE URILIZATION

The purpose of this test is to identify organisms capable of using sodium citrate as the sole carbon source and inorganic ammonium salts as the sole nitrogen source. The test is part of a series referred to as IMViC (indole, methyl red, Voges-Proskauer, and citrate), which is used to differentiate Enterobacterales from other gram-negative rods.

COAGULASE TEST

The test is used to differentiate Staphylococcus aureus (positive) from coagulase-negative staphylococci (negative).

DECARBOXYLASE TEST

This test is used to differentiate decarboxylase-producing Enterobacterales from other gram-negative rods

DEOXYRIBONUCLEIC ACID TEST

This test is used to differentiate organisms based on the production of deoxyribonuclease. It is used to distinguish Serratia spp. (positive) from Enterobacter spp., Staphylococcus aureus (positive) from other species, and Moraxella catarrhalis (positive) from Neisseria spp.

ESCULIN HYDROLYSIS

This test is used for the presumptive identification and differentiation of Enterobacterales.

ENTEROBACTER AEROGENES
BLUE PRECIPITATE / GROWTH

WHATS THE EXPECTED POSITIVE RESULT IN CITRATE UTILIZATION
WHAT ORGANISM
WHAT PRECIPITATE

ESCHERICHIA COLI
NO GROWTH/GREEN

WHATS THE EXPECTED GENATIVE RESULT IN CITRATE UTILIZATION
WHAT ORGANISM
WHAT PRECIPITATE

STAPHYLOCOCCUS EUREUS
COAGULASE LESS THAN 10SEC

WHAT IS THE EXPECTED POSITIVE RESULT IN COAGULASE TEST
ORGANISM
OBSERVED OUTCOME

STAPHYLOCOCCUS EPIDERMIS
NO COAGULASE

WHAT IS THE EXPECTED NEGATIVE RESULT IN COAGULASE
WHAT ORG
WHAT OBSERVED

YELLOW TO PURPLE
KEP

WHAT IS THE EXPECTED POSITIVE RESULT IN DECARBOXYLASE
WHAT ORGANISM
WHAT OBSERVED

KE
YELLOW

WHAT IS THE EXPECTED NEGATIVE RESULT IN DECARBOXYLASE
WHAT ORGANISM
WHAT OBSERVED

STAPHYLOCOCCUS EUREUS
CLEARING SURROUNDINGS

WHAT IS THE EXPECTED POSITIVE OUTSOME IN DEOXYRIBONUCLEIC ACID TEST
WHAT ORGANISM
WHAT OBSERVED

ESCHERICHIA COLI
NO CLEARING

WHAT IS THE EXPECTED NEGATIVE OUTCOME OF DEOXYROBUNUCLEIC ACID
WHAT ORGANISM
WHAT APPEARANCE

BLACKING SHOWED LOSS OF FLUORESCENT
ESTEROCOCCUS FAECALIS

WHAT IS THE EXPECTED POSITIVE RESULT OG BILE ESCULIN
WHAT ORGANISM
WHAT OBSERVED

ESCHERICHIA COLI
NO BLACKING AND NO SHOWED FLUORESCENT

WHAT IS THE EXPECTED NEGATIVE RESULT OF BILE ESCULIN
WHAT ORGANISM
WHAT OBSERVED