Hemolysins in S. aureus

Pink to red

Enriched medium

Staphylococci

<p>High salt concentration (7.5% NaCl)</p> Signup and view all the answers

<p>Yellow</p> Signup and view all the answers

<p>Halotolerant staphylococci</p> Signup and view all the answers

<p>Medium to large (1-2 mm in diameter), off-white or gray</p> Signup and view all the answers

<p>They produce golden yellow pigments 'lipochrome'</p> Signup and view all the answers

<p>It means 'golden'</p> Signup and view all the answers

<p>Small to medium, opaque, gray-white</p> Signup and view all the answers

<p>They are large, very glossy, smooth, opaque, butyrous, convex</p> Signup and view all the answers

<p>Yellow colonies with yellow discoloration of the medium</p> Signup and view all the answers

<p>To render the medium selective for G+ bacteria by inhibiting G- bacteria.</p> Signup and view all the answers

<p>Atypical reactions may be observed.</p> Signup and view all the answers

<p>Through potassium tellurite, lithium chloride, and glycine which inhibit nonstaphylococcal organisms, both G+ and G- bacteria.</p> Signup and view all the answers

<p>Phenol red</p> Signup and view all the answers

<p>By reducing tellurite to metallic tellurium, resulting in black or gray-black colonies.</p> Signup and view all the answers

<p>Because the document is the property of SLU and is for their exclusive use.</p> Signup and view all the answers

<p>Acts primarily as a surfactant or a detergent-like molecule that interacts with cell membranes and forms channels resulting in slow leakage of cellular contents.</p> Signup and view all the answers

<p>Composed of two proteins designated S and F. It lyses white blood cells by causing pore formation in the cellular membranes, increasing cation permeability, leading to degranulation, cell swelling, and lysis.</p> Signup and view all the answers

<p>PVL is produced by lysogenized strains of S.aureus and is active against neutrophils, causing tissue necrosis. It consists of two components, S and F, that act synergistically on the white blood cell membrane.</p> Signup and view all the answers

<p>TSST-1 is a superantigen that promotes the manifestations of toxic shock syndrome. It stimulates T cells non-specifically, resulting in polyclonal T-cell activation.</p> Signup and view all the answers

<p>Superantigens stimulate T cells non-specifically by directly cross-linking T-cell receptor (TCR) to MHC class II molecules on APCs outside of the antigen-binding site.</p> Signup and view all the answers

<p>Affected cells undergo degranulation of the cytoplasm, cell swelling, and lysis.</p> Signup and view all the answers

<p>To determine whether bacteria can utilize glucose in the presence or absence of oxygen.</p> Signup and view all the answers

<p>Two tubes are inoculated by stabbing; one tube is overlaid with sterile mineral oil (closed tube) and the other tube is exposed to oxygen (open tube).</p> Signup and view all the answers

<p>Because Micrococci are oxidative, producing acids from glucose only in the presence of oxygen.</p> Signup and view all the answers

<p>Staphylococci are fermentative, utilizing glucose and producing acids in both presence and absence of oxygen.</p> Signup and view all the answers

<p>Staphylococci can be differentiated by the yellow color change of the medium in both open and closed tubes due to bound coagulase production.</p> Signup and view all the answers

<p>Bromthymol blue is used as a pH indicator in the O-F test.</p> Signup and view all the answers