Biochemical Test of Brucella melitensis

Biochemical Test of Brucella melitensis

Brucella melitensis

Biochemical Test of Brucella melitensis

Within the genus Brucella, there exists a species of Gram-negative bacteria called Brucella melitensis. The virus in question is facultative intracellular and is responsible for brucellosis, a zoonotic infectious disease that predominantly affects animals but can potentially infect people and cause a crippling fever.

Goats and sheep are the main animals that are infected by Brucella melitensis, but it can also infect cattle, pigs, dogs, and other domestic and wild animals. Usually, humans contract the virus by eating unpasteurized dairy products contaminated with Brucella germs or by coming into close contact with affected animals.

Biochemical Test

Several biochemical assays can be used to identify the Gram-negative bacterium Brucella melitensis, which causes brucellosis in both people and animals. The following are a few of the often employed biochemical assays to identify Brucella melitensis:

Catalase Test

Testing for the presence of the enzyme catalase, which catalyzes the conversion of hydrogen peroxide into water and oxygen, indicates that Brucella melitensis is catalase-positive.

Oxidase test

It usually shows a positive result for oxidase, suggesting the presence of the enzyme cytochrome c oxidase.

Urease Test

It generates the enzyme urease, which hydrolyzes urea into ammonia and carbon dioxide. This means that the bacteria is urease-positive.

Nitrate Reduction

Biochemical Test of Brucella melitensis

It usually exhibits negative nitrate reduction, which means that it does not convert nitrate into nitrite or nitrogen gas.

Use of Carbon Sources

Being a finicky organism, Brucella melitensis needs enriched conditions to flourish. Carbs are neither fermented by it nor used as fuel.

Production of H2S

In most cases, Brucella melitensis produces no hydrogen sulphide (H2S).

Growth Features

It is a slow-growing plant that needs certain growing environments, such elevated CO2 and enriched media.

Hydrolysis of Gelatin

The ability of bacteria to create gelatinase, which breaks down gelatin into simpler forms, is determined by the gelatin hydrolysis test. Usually, gelatin is not hydrolyzed by Brucella melitensis.

Production of Indoles

Using Kovac’s reagent, this test establishes if bacteria can synthesize indole from the amino acid tryptophan. Usually, It is indole-negative.

Fermentation of Sugar

Glucose, lactose, and sucrose are among the sugars that Brucella melitensis can ferment. Different sugar fermentation test medium, including Hugh-Leifson agar or Triple Sugar Iron (TSI) agar, can be used to investigate patterns of fermentation.

API 20E Test

Enterobacteriaceae and other non-fastidious gram-negative rods can be identified using the commercial kit API 20E system. It comprises of a number of biochemical tests, such as those for the creation of particular enzymes, the fermentation of different sugars, and the use of diverse substrates.

MALDI-TOF MS

Bacterial identification can be done quickly and accurately by Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry, or MALDI-TOF MS. It uses the distinct mass spectra of proteins or peptides produced from bacterial samples to accurately identify different species of Brucella.

Serological Tests

Biochemical Test of Brucella melitensis

It infections can also be diagnosed and serotyped using serological tests such complement fixation and agglutination assays (such as the Rose Bengal test and slide agglutination test).

These assays aid in the precise identification and characterization of Brucella melitensis, supporting the diagnosis and treatment of brucellosis, in conjunction with clinical and epidemiological data.

Frequently Asked Questions(FAQ)

What is Brucella melitensis?

It is a facultative intracellular Gram-negative species that causes brucellosis, commonly referred to as Malta fever or Mediterranean fever. Although humans are not typically afflicted, it can infect goats, sheep, and other ruminants. The condition is febrile and manifests as fever, sweating, weakness, malaise, and joint pain.

What do you mean by Serological Tests?

It infections can also be diagnosed and serotyped using serological tests such complement fixation and agglutination assays (such as the Rose Bengal test and slide agglutination test).

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