EXAMINATION OF THE GLYCOCALYX OF 4 SPECIES OF STAPHYLOCOCCUS BY TRANSMISSION ELECTRON-MICROSCOPY AND IMAGE-ANALYSIS

The coagulase-negative staphylococci have become important pathogens i n human infections involving foreign bodies. The bacterial glycocalyx is a major mediator of attachment of these organisms to medical device s, but the glycocalyx is sometimes difficult to demonstrate. A combina tion of the techniques of transmission electron microscopy (TEM) and i mage analysis enabled investigators to reveal the glycocalyx which was previously indiscernible. Eight strains of coagulase-negative staphyl ococci, including Staphylococcus epidermidis, S. hominis, S. lugdunens is, and S. schleiferi subspecies schleiferi, were grown, treated with anti-staphylococcal serum to stabilize the glycocalyx, and examined by TEM. Image analysis of negatives was then used to enhance the visual images which showed far more glycocalyx than previously seen by TEM al one.