Influence of cell shape and surface charge on attachment of Mycoplasma pneumoniae to glass surfaces.

Attachment of Mycoplasma pneumoniae to glass is reduced in the presence of protein, and fatty acid-free bovine serum albumin is more effective than Cohn fraction V. Cultures in the early log phase (pH 7.45 to 7.25) and cultures in the stationary or decline phase (pH 6.9 to 6.4) were more sensitive to this inhibiting effect of protein-containing buffer. Treatment of the glass surface with bovine serum albumin, concanavalin A, or polylysine reduced attachment of the mycoplasma cells. The inhibiting effects of both proteins in buffer or on the glass surface could be overcome by the addition of glucose. Modification of the mycoplasma surface charge by blocking of carboxyl groups or neutralization of ionic lipids by tetracaine altered the attachment level, whereas fibronectin and its corresponding antiserum were without effect. The results suggest that the mycoplasma interaction with glass is a complex multifactorial process. In protein-free buffer both hydrophobic and electrostatic forces are involved; in protein-containing fluid, other factors seem to be involved. The energy required for this type of attachment could be necessary for maintenance of cell shape or synthesis of polypeptides.