Blog
About

  • Record: found
  • Abstract: found
  • Article: found
Is Open Access

Human Sperm Interaction with Staphylococcus aureus: A Molecular Approach

, *

Journal of Pathogens

Hindawi Publishing Corporation

Read this article at

Bookmark
      There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

      Abstract

      Sperm immobilization factor (SIF) causing 100% immobilization of spermatozoa isolated from Staphylococcus aureus when characterized using LC-MS (Liquid chromatography-mass spectrometry) showed that this 20 kDa protein had peptide sequence similarity with hsp-70 protein. It was found to completely (100%) inhibit Mg ++ ATPase activity of spermatozoa at concentration of 100  μ g mL −1. Sperm samples treated with SIF also showed reduction in calcium ionophore-induced acrosome reaction as compared to control samples (treated with calcium ionophore alone). Binding studies of FITC labelled SIF with spermatozoa using fluorescent microscopy showed binding of SIF to the surface of spermatozoa indicating the presence of SIF binding receptor. The receptor was extracted by 3M NaCl and purified by gel permeation chromatography. Characterization of the receptor by MALDI-TOF (Matrix-assisted laser desorption ionization-time of flight) indicated that the receptor shared sequence similarity with MHC class II antigen. A calorimetric study showed that the receptor moiety on spermatozoa was specific for the purified ligand as binding of the receptor to ligand was enthalpically (−11.9 kJ mole −1) as well as entropically (21.53 J mole −1 K −1) favored resulting in the Gibb's free energy of −18.57 kJ mole −1.

      Related collections

      Most cited references 45

      • Record: found
      • Abstract: not found
      • Article: not found

      WHO Laboratory Manual for the Examination and Processing of Human Semen

        Bookmark
        • Record: found
        • Abstract: found
        • Article: not found

        Improved pregnancy rate in human in vitro fertilization with the use of a medium based on the composition of human tubal fluid.

        Significantly more mouse zygotes developed to blastocysts in culture in a medium formulated on the composition of human tubal fluid (HTF) than in modified Tyrode's medium (T6). In a randomized 2 X 2 factorial trial of human in vitro fertilization that compared the two media and culture under oil versus culture in loosely capped tubes, significantly more clinical pregnancies (30% of 60 transfers) were obtained with HTF medium than with T6 medium (11% of 53 transfers). Decreasing the K+ content of HTF medium to that present in T6 medium significantly decreased the number of mouse zygotes that developed in culture. Modifying Ca++ levels had no effect. It is therefore likely that the higher K+ content in HTF medium is primarily responsible for the superiority of HTF medium over T6 medium, but other differences in the composition of the two media could contribute to the results observed.
          Bookmark
          • Record: found
          • Abstract: found
          • Article: not found

          FLAGELLAR MOVEMENT AND ADENOSINE TRIPHOSPHATASE ACTIVITY IN SEA URCHIN SPERM EXTRACTED WITH TRITON X-100

          Extraction with 0 04% (w/v) Triton X-100 removes the flagellar membrane from sea urchin sperm while leaving the motile apparatus apparently intact When reactivated in a suitable medium containing exogenous adenosine triphosphate (ATP), nearly 100% of the sperm are motile and they swim in a manner resembling that of live sperm. Under standard conditions, with 1 mM ATP at 25°C, the reactivated sperm had an average frequency of 32 beats/sec and progressed forward a distance of 2.4 µm/beat; comparable figures for live sperm in seawater were 46 beats/sec and 3 9 µm/beat. The adenosine triphosphatase (ATPase) activity of the reactivated sperm was measured with a pH-stat in the presence of oligomycin to inhibit residual mitochondrial ATPase. The motile sperm had an ATPase activity of 0.16 µmole Pi/(min x mg protein), while sperm that had been rendered non-motile by homogenizing had an activity of 0 045 µmole Pi/(min x mg protein). The difference between the ATPase activities of the motile and nonmotile sperm was tentatively interpreted as the amount of activity coupled to movement, and under optimal conditions it amounted to about 72% of the total ATPase activity Under some conditions the movement-coupled ATPase activity was proportional to the beat frequency, but it was possibly also affected by other wave parameters. The coupled ATPase activity decreased to almost zero when movement was prevented by raising the viscosity, or by changing the pH or salt concentration. The motility of reactivated sperm was wholly dependent on the presence of ATP; other nucleotides gave very low phosphatase activity and no movement. The requirement for a divalent cation was best satisfied with Mg++, although some motility was also obtained with Mn++ and Ca++. The coupled ATPase activity had a Michaelis constant (Km ) of 0.15 mM. The beat frequency of the reactivated sperm varied with the ATP concentration, with an effective "Km " of 0.2 mM.
            Bookmark

            Author and article information

            Affiliations
            Department of Microbiology, Panjab University, Chandigarh 160014, India
            Author notes

            Academic Editor: Hin-Chung Wong

            Journal
            J Pathog
            J Pathog
            JPATH
            Journal of Pathogens
            Hindawi Publishing Corporation
            2090-3057
            2090-3065
            2012
            15 October 2012
            : 2012
            23119166
            3478719
            10.1155/2012/816536
            Copyright © 2012 S. Gupta and V. Prabha.

            This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

            Categories
            Research Article

            Infectious disease & Microbiology

            Comments

            Comment on this article