What bacteria can produce indole?

many pathogenic bacteria such as Bacillus alvei, pathogenic E. coli, several Shigella strains, Enterococcus faecalis, and V. cholerae, can produce indole.

What is the enzyme that is present in a positive indole test?

Indole test is a biochemical test conducted on bacterial species to detect their ability to produce indole from tryptophan in the presence of a group of enzymes called ‘tryptophanase’. It is a qualitative test that tests the conversion of tryptophan into indole.

What is the principle of indole production test?

Principle of Indole Test Indole is generated by reductive deamination from tryptophan via the intermediate molecule indolepyruvic acid. Tryptophanase catalyzes the deamination reaction, during which the amine (-NH2) group of the tryptophan molecule is removed.

What is the treatment for Gram negative rods?

Vancomycin can be used for gram-positive cocci, ceftriaxone for gram-negative cocci, and ceftazidime for gram-negative rods. If the Gram stain is negative, but there is strong clinical suspicion for bacterial arthritis, treatment with vancomycin plus ceftazidime or an aminoglycoside is appropriate.

What are antibiotics used for Gram negative rods?

Several classes of antibiotics have been designed to target gram-negative bacteria, including aminopenicillins, ureidopenicillins, cephalosporins, beta-lactam-betalactamase combinations (e.g. pipercillin-tazobactam), Folate antagonists, quinolones, and carbapenems.

What does Gram negative rods mean?

Gram negative rods is just one way of describing bacteria that meet certain classifications. Gram stains can be either negative or positive, and rods are long skinny bacteria like two lower case “Ls” put together – like this ll instead of round like cocci, two of which look like this – οο.

What is Gram positive antibiotic?

Penicillin, erythromycins and the cephalosporins are medium spectrum antibiotics and are very effective against the Gram positive bacteria. Polymyxins are considered to be narrow spectrum antibiotics because these can be effective against few species of bacteria. It belongs to the bacteria of genus Streptomyces.