Chapter 35 : Respiration and Small-Colony Variants of Staphylococcus aureus

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respiration and carbohydrate metabolism follow patterns very similar to those in , with glycolysis in staphylococci following the nearly universal patterns found in all biological systems. Reactions that are favored in respiratory-deficient small-colony variants (SCVs) are shown in a table, and it is apparent that these variants are optimizing reactions that produce ATP and oxidize NADH by non-oxygen-dependent mechanisms. Although mutations in any essential gene can cause slow growth and small colonies, this chapter considers a subset of these mutants that was first observed in patients who had unusually persistent infections and were later found to have defects in oxidative metabolism and electron transport. This chapter focuses on multiple phenotypic changes associated with interrupted electron transport. It was also found that bacterial electron transport inhibitors Z69 and Z90 are able to reproduce the SCV phenotype. JB-1 is a menadione auxotrophic SCV that was selected with gentamicin from its parent, 6850. Some hemin auxotrophs selected by resistance to gentamicin have also been characterized in detail. Although many different mutations might produce slow growth, menadione and hemin auxotrophs predominate among clinical SCV isolates. Finally, the chapter talks about instability of the SCV phenotype, SCVs and antibiotic resistance, and electron transport, respiration, and toxin production in .

Citation: Proctor R. 2006. Respiration and Small-Colony Variants of Staphylococcus aureus, p 434-442. In Fischetti V, Novick R, Ferretti J, Portnoy D, Rood J (ed), Gram-Positive Pathogens, Second Edition. ASM Press, Washington, DC. doi: 10.1128/9781555816513.ch35

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Electron Transport System
Cell Wall Biosynthesis
Aortic Valve Endocarditis
Fatty Acid Biosynthesis
Toxic Shock Syndrome
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Relationship between electron transport and the small-colony variant phenotype in .

Citation: Proctor R. 2006. Respiration and Small-Colony Variants of Staphylococcus aureus, p 434-442. In Fischetti V, Novick R, Ferretti J, Portnoy D, Rood J (ed), Gram-Positive Pathogens, Second Edition. ASM Press, Washington, DC. doi: 10.1128/9781555816513.ch35
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Generic image for table

Redox and ATP-producing reactions in SCVs

Abbreviations: ADH, alcohol dehydrogenase; ArcA = arginine deiminase; ArcB = ornithine transcarbamolyase; ArcC = carbamoylate kinase; CitB = aconitase; FadB = 3-hydroxyacyl-CoA dehydrogenase: HMP, hydroxymonocarboxylic acid phosphatase (flavohemoprotein or pyruvate/nitrite reductase); LDH =lactate dehydrogenase; MltD = mannitol-1-phosphate 5-dehydrogenase; Mqo2 - malate:quinone oxidoreductase; PycA = pyruvate carboxylase; PdhB = pyruvate dehydrogenase El component beta subunit; PflB = pyruvate formate lyase.

SA0182 and SA0224 refer to gene numbers in the N315 genome.

Citation: Proctor R. 2006. Respiration and Small-Colony Variants of Staphylococcus aureus, p 434-442. In Fischetti V, Novick R, Ferretti J, Portnoy D, Rood J (ed), Gram-Positive Pathogens, Second Edition. ASM Press, Washington, DC. doi: 10.1128/9781555816513.ch35

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