What tests are used to identify Staphylococcus aureus?

Coagulase testing is the single most reliable method for identifying Staphylococcus aureus [9]. Coagulase production can be detected using either the slide coagulase test (SCT) or the tube coagulase test (TCT).

What are the biochemical characters of Staphylococcus aureus?

The species is identified on the basis of a variety of conventional physiological or biochemical characters. The key characters for Staphylococcus aureus are colony pigment, free coagulase, clumping factor, protein A, heat-stable nuclease, lipase, and acid production from mannitol [1].

What is a rapid biochemical test for the identification of Staphylococcus aureus?

Biochemical tests used to confirm S. aureus were coagulase test, catalase test, indole production, methyl red test, Voges-proskauer reaction, urease production, citrate utilization and sugar fermentation [12].

What are the biochemical test for Staphylococcus epidermidis?

VetBact

Species/Subspecies: Staphylococcus epidermidis
Metabolism: Facultatively anaerobic
Catalase/Oxidase: +/-
Other Enzymes: Coagulase-, esculinase -, ornithine decarboxylase -, tryptophanase -, urease +.
Biochemical Tests: Citrate -, hydrogen sulfide (H2S) +, methyl red -, Voges-Proskauer +.

What is biochemical test microbiology?

Biochemical tests are the tests used for the identification of bacteria species based on the differences in the biochemical activities of different bacteria. Bacterial physiology differs from one type of organism to another.

What is the novobiocin test what is it used for?

Remel Novobiocin Disk is a reagent-impregnated disk recommended for use in qualitative procedures to differentiate Staphylococcus saprophyticus from other coagulase-negative staphylococci.

What is the DNase test?

Principle. The deoxyribonuclease (DNase) test detects the degradation of DNA by bacterial species that produce DNase. The DNase test may be performed on plate media and is available in some commercial tests, e.g., QuadFERM+.

What are biochemical characters?

The physiological and biochemical traits include data on growth at different temperatures, pH values, salt concentrations, atmospheric conditions (aerobic/anaerobic), growth in the presence of various substances such as antimicrobial agents, and data on the presence or activity of various enzymes, metabolization of …

Is S epidermidis urease positive?

It is positive for urease production, is oxidase negative, and can use glucose, sucrose, and lactose to form acid products. In the presence of lactose, it will also produce gas.

Is s Saprophyticus DNAse positive?

In the present study, two (2.3%) of the 84 CoNS strains were DNAse positive, a finding confirming the production of this enzyme by CoNS. The DNAse test showed good correlation with the coagulase test and with the detection of the coa gene for S.

What are the different types of biochemical test?

Summary of Biochemical Tests

What is the positive result for indole test?

A positive result is shown by the presence of a red or red-violet color in the surface alcohol layer of the broth. A negative result appears yellow. A variable result can also occur, showing an orange color as a result.

What biochemical test can we use to differentiate S aureus from S epidermidis?

multiplex PCR aureus and Staph. epidermidis. Accordingly, a multiplex PCR was developed and we found that a single gene encoding the adhesin fibrinogen binding protein could be used to identify and differentiate the two species.

What is catalase test?

This test is used to identify organisms that produce the enzyme, catalase. This enzyme detoxifies hydrogen peroxide by breaking it down into water and oxygen gas. The bubbles resulting from production of oxygen gas clearly indicate a catalase positive result.

Is Gram staining a biochemical test?

Biochemical tests are applied to the appropriate specimen and include gram staining followed by culturing the bacterial isolate in mannitol salt agar.

What is a biochemistry test for?

The biochemical profile is a series of blood tests used to evaluate the functional capacity of several critical organs and systems, such as the liver and kidneys. These tests can be done on an empty stomach or not, and are usually accompanied by a complete blood count (CBC).

What is the significance of biochemical test?

Biochemical tests are the tests used for the identification of bacteria species based on the differences in the biochemical activities of different bacteria.

What are the biochemical test for bacteria identification?

Each species of bacteria has specific metabolic needs and relies on different enzymes to fuel those unique needs. The presence of catalase, gelatinase, oxidase, urease, for example, can be used to identify the species of bacteria. Biochemical reactions used in biochemical tests depend on the presence of such bacteria.

What is D test in microbiology?

D test is a simple disc diffusion test giving high throughput results. It is used to study the macrolide lincosamide streptogramin resistance (MLSB), both constitutive and inducible as well as macrolide streptogramin resistance (MSB) in Staphylococcus aureus.

What is modified oxidase test?

The oxidase method was originally described by Kovacs in 1956 as a method of differentiating gram-negative bacilli. However, in 1981, Faller and Schleifer modified Kovacs’ oxidase reagent by utilizing a tetramethyl-pphenylenediamine (TMPD) in dimethyl sulfoxide (DMSO). This is referred to as the modified oxidase test.

What is sensitive to novobiocin?

Novobiocin susceptibility test results are 100% sensitive and 96% specific. S. saprophyticus is innately resistant to the antibiotic novobiocin. Therefore, screening coagulase-negative staphylococci from urine cultures for novobiocin resistance is reliable presumptive identification of S.

Is S aureus DNase positive?

After application and penetration of hydrochloric acid into the medium, DNase positive organisms such as Staphylococcus aureus or Serratia marcescens will be surrounded by clear zones of depolymerized DNA while the medium farer away from the inoculation band will be opaque and whitish due to polymerized DNA.

Is MacConkey agar selective or differential?

MacConkey agar is an example of a medium that is both differential and selective. The presence of bile salts, as well as crystal violet, within the media prevent gram-positive organisms from growing.

What is the gelatin hydrolysis test?

Gelatin hydrolysis test is used to detect the ability of an organism to produce gelatinases that liquefy gelatin. This process takes place in two sequential reactions. In the first reaction, gelatinases degrade gelatin to polypeptides. Then, the polypeptides are further converted into amino acids.

How is biochemistry used in microbiology?

Although biochemistry is not limited to microorganisms, it’s related to microbiology in that it allows microbiologists and biochemists to understand the biological processes associated with these organisms as well as the production and functions of various biomolecules.

What are the biochemical characteristics of bacteria?

A Few Biochemical/Physiological Properties Used for identification of bacteria include: nutrient utilization (carbohydrate utilization, amino acid degradation, lipid degradation), resistance to inhibitory substances (high salt, antibiotics, etc.), enzyme production (catalase, coagulase, hemolysins, etc.) and motility.

What is a biochemical characterization?

Biochemical characterization involves a determination of the biochemical properties of the bacteria or sample.

Why is E coli methyl red positive?

When the VP reagents are added to MR-VP broth that has been inoculated with Escherichia coli , the media turns a copper color. This is a negative result for the VP test. When the VP reagents are added to MR-VP broth that has been inoculated with Enterobacter cloacae , the media turns red. This is a positive VP result.

Is Staphylococcus Saprophyticus citrate positive or negative?

Staphylococcus saprophyticus is a coagulase-negative species of Staphylococcus. Like other Staphylococci, it is Gram-positive, is globular shaped, and is a facultative anaerobe.

Is Staphylococcus Saprophyticus catalase positive?

Staph saprophyticus is catalase positive, so it makes an enzyme called catalase. We can use this to differentiate Staph saprophyticus from other gram positive cocci, like streptococci and enterococci, which are catalase negative.