Purification and characterization of aminoglycoside-modifying enzymes from Staphylococcus aureus and Staphylococcus epidermidis.

A method was developed to purify diacetyl-reducing enzymes from Staphylococcus aureus. Two enzymes capable of catalysing diacetyl reduction were isolated, neither of which turned out to be a specific diacetyl reductase. One of them is a lactate dehydrogenase similar to the one from Staphylococcus epidermidis, which accepts diacetyl, although poorly. The other one uses as coenzyme beta-NAD and reduces uncharged alpha-dicarbonyls with more than three carbon atoms (especially the alpha-diketones diacetyl and pentane-2,3-dione), producing the L(+) form of the corresponding alpha-hydroxycarbonyls. This enzyme has an Mr of 68,000 and is, most probably, a monomer. Its optimum pH is 6.0. Its shows a high affinity for NADH and a rather low one for diacetyl, which, at least in vitro, does not seem to be as good a substrate as pentane-2,3-dione. We propose for it the systematic name L-alpha-hydroxyketone: NAD+ oxidoreductase and the recommended name of alpha-diketone reductase (NAD). We also suggest that the diacetyl reductase entry in the I.U.B. classification be suppressed.

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Isolation, purification and characterization of glucokinase from Staphylococcus aureus

Journal of Pharmacy Research ◽

10.1016/j.jopr.2012.11.042 ◽

2013 ◽

Vol 6 (1) ◽

pp. 205-209

Author(s):

Rathnakar Reddi KVN ◽

Santhosh Kumar Pasupuleti ◽

Venkateswara Prasad Uppu ◽

Yeswanth Sthanikam ◽

Swarupa Vimjam ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Purification And Characterization

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Detection and partial characterization of extracellular inducers of persistence in Staphylococcus epidermidis and Staphylococcus aureus

Journal of Medical Microbiology ◽

10.1099/jmm.0.001392 ◽

2021 ◽

Vol 70 (6) ◽

Author(s):

Elyse C. Curry ◽

Ryan G. Hart ◽

Danni Y. Habtu ◽

Neal R. Chamberlain

Keyword(s):

Molecular Weight ◽

Staphylococcus Aureus ◽

Staphylococcus Epidermidis ◽

Type Species ◽

Proteinase K ◽

Partial Characterization ◽

Content Type ◽

Link Type ◽

Inducing Factors

Introduction. This study describes the identification and partial characterization of persistence-inducing factors (PIFs) from staphylococci. Hypothesis/Gap Statement. Increases in persisters during mid-log phase growth indicate that quorum-sensing factors might be produced by staphylococci. Aim. To identify and partially characterize PIFs from Staphylococcus epidermidis RP62A and Staphylococcus aureus SH1000. Methodology. Others have demonstrated a significant increase in persister numbers during mid-log phase. Inducers of this mid-log increase have yet to be identified in staphylococci. Optical density at 600 nm (OD600) was used instead of time to determine when persister numbers increased during logarithmic growth. Concentrated culture filtrates (CCFs) from S. epidermidis and S. aureus were obtained at various OD600s and following incubation at 16 h. The CCFs were used to develop a PIF assay. The PIF assay was used to partially characterize PIF from S. epidermidis and S. aureus for sizing of PIF activity, temperature and protease sensitivity and inter-species communications. Results. The optimal OD600s for S. epidermidis and S. aureus PIF assays were 2.0 and 0.5, respectively. The highest PIF activity for both species was from CCF following incubation overnight (16 h). S. epidermidis ’ PIF activity was decreased by storage at 4 oC but not at 20 oC (16 h), 37 oC (1 h) or 100 oC (15 min). S. aureus ’ PIF activity was decreased following storage at 4 oC (2 weeks) and after boiling at 100 oC for 5 min but not after incubation at 37 oC (1 h). PIF activity from both species went through a 3000 molecular weight cutoff ultrafilter. Proteinase K treatment of S. aureus PIF decreased activity but did not decrease the PIF activity of S. epidermidis . PIF from S. epidermidis did not increase persisters when used to treat S. aureus cells and nor did PIF from S. aureus increase persisters when used to treat S. epidermidis cells. Conclusions. Attempts to discover PIFs for staphylococci were unsuccessful due to the time-based means used to identify mid-log. Both staphylococcal species produce extracellular, low-molecular-weight inducers of persistence when assayed using an OD600 -based PIF assay.

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Characterization of Lipases from Staphylococcus aureus and Staphylococcus epidermidis Isolated from Human Facial Sebaceous Skin

Journal of Microbiology and Biotechnology ◽

10.4014/jmb.1107.07060 ◽

2012 ◽

Vol 22 (1) ◽

pp. 84-91 ◽

Cited By ~ 13

Author(s):

Winny Xie

Keyword(s):

Staphylococcus Aureus ◽

Staphylococcus Epidermidis

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Microbiological Characterization of Human Milk1

Journal of Food Protection ◽

10.4315/0362-028x-40.9.614 ◽

1977 ◽

Vol 40 (9) ◽

pp. 614-616 ◽

Cited By ~ 22

Author(s):

A. GAVIN ◽

K. OSTOVAR

Keyword(s):

Staphylococcus Aureus ◽

Breast Feeding ◽

Staphylococcus Epidermidis ◽

Lactobacillus Acidophilus ◽

Bacterial Population ◽

Streptococcus Salivarius ◽

Streptococcus Mitis ◽

Bacterial Populations ◽

Milk Samples

Milk samples of five breast-feeding mothers were studied for bacterial population, flora, and source. In most instances, samples taken at postfeeding contained higher bacterial populations than prefeeding samples. Staphylococcus epidermidis was the predominant organism isolated from 100% of the samples. Increases were noticed in the appearance of Streptococcus mitis, Gaffkya tetragena, Streptococcus salivarius, Staphylococcus aureus, as well as Lactobacillus acidophilus, in the postfeeding samples. Main sources of bacteria were found to be the infant's mouth and maternal skin.

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