aureus isolates showed positive results in gelatin, urea and galactose hydrolysis test, 50% isolates were positive in starch hydrolysis test, 35% in protein hydrolysis test, 100% isolates in lactose fermenting test, but no isolate was positive in sucrose fermenting test.
Does Staphylococcus aureus test positive for urease?
Over 90% of S. aureus strains are urease-producing [21], which is encoded by the urease gene cluster ureABCEFGD.
What is a positive test for starch hydrolysis?
Positive test: A clear zone around the line of growth after addition of iodine solution indicates that the organism has hydrolyzed starch. Negative test:A blue, purple, or black coloration of the medium (depending on the concentration of iodine).
Is Staph aureus PYR positive or negative?
aureus are catalase and coagulase positive, only SIG species are PYR positive . Both are negative for ornithine decarboxylase. However, an ornithine-positive Staphylococcus species that also gives a positive reaction in latex agglutination and PYR testing is Staphylococcus lugdunensis.
Does Staphylococcus aureus hydrolyze starch?
The enzyme gelatinase was secreted from bacteria, hydrolysis the gelatin into soluble carbohydrates. Thus isolated S. aureus liquefy gelatin and showed positive results [16]. ... It was evident from this study, 50% strains showed a positive result in starch hydrolysis test.
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).
Does Staphylococcus aureus produce amylase?
α-amylase is one of the enzymes secreted by S. aureus which catalyses the breakdown of complex sugars to monosaccharides, which are required for colonization and survival of this pathogen in any anatomical locales.
What is the indicator of starch hydrolysis test?
The test utilizes iodine as an indicator. Starch in the presence of iodine produces a dark blue coloration of the medium as iodine is trapped in the helical structure of starch and a yellow zone or clear zone around a colony in a blue medium indicates amylolytic activity.
What is the enzyme that breaks down starch?
Animals living alongside humans have multiple copies of the gene for alpha-amylase , the enzyme that breaks down starchy foods, and high levels of this protein in their saliva.
What bacteria metabolizes starch?
The zone of clearing surrounding Bacillus megaterium and Bacillus subtilis indicate that both were able to hydrolyze starch.
Does Staphylococcus produce gas?
Staphylococcus aureus may cause subacute necrotizing fasciitis, and infection with this organism should be considered in cases of soft-tissue infection with gas formation in diabetics.
What color will indicate a positive urease test?
Urease production is indicated by a bright pink (fuchsia) color on the slant that may extend into the butt. Note that any degree of pink is considered a positive reaction.
What bacteria are urease positive?
Many bacteria carry the urease enzyme in different human ecosystems, but Helicobacter pylori is the only known bacterium showing urease activity in gastric ecosystems. For this reason, the rapid urease test (RUT) on gastric biopsies and urea breath test (C-UBT) are used to detect H. pylori infection.
Is Staphylococcus aureus motile or nonmotile?
Staphylococcus aureus is historically regarded as a non-motile organism . More recently it has been shown that S. aureus can passively move across agar surfaces in a process called spreading.
Does Staphylococcus aureus reduce nitrate?
Staphylococcus carnosus reduces nitrate to ammonia in two steps. ... Syntheses of both enzymes are inhibited by oxygen and induced to greater or lesser degrees by nitrate or nitrite, respectively. In whole cells, nitrite reduction is inhibited by nitrate and also by high concentrations of nitrite (> or = 10 mM).
What are the biochemical characters of Staphylococcus aureus?
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].
