Summary: Fifteen bacterial isolates (12 streptococcal and 3 staphylococcal strains) from patients with bacterial endocarditis were screened for a variety of surface receptors, in an attempt to identify a common feature that might contribute to their ability to attach to and colonize damaged heart tissue. The bacterial receptors screened for, using a dot-blot autoradiographic procedure, included those for the Fc region of human IgG, fibrinogen, fibronectin and human Clq. Bacteria with receptors for each of the probes used could be identified, but no common receptor was present on all endocarditis-causing strains.
Summary: Saccharomyces cerevisiae, when growing exponentially in batch culture, passed through a phase in which, on average, one cell in 104survived plating onto a low water activity (a w) agar medium. Stationary phase cultures were resistant as were all other species tested, with the exception of Candida krusei. In continuous culture, S. cerevisiae was more resistant at low than at high dilution rates. Plating at low a w was lethal to those cells that were not protected by an adequate content of compatible solute. In naturally resistant yeasts and in S. cerevisiae that had been exposed to an adaptation process, the compatible solute was one or more types of polyhydric alcohol. Resistance in stationary phase was attributable to a different cause.
Summary: Oxygen and substrate gradients were simulated with a finite-volume method for a variety of bacterial colony sizes and substrate concentrations. A spherical segment geometry and a Monod relationship for simultaneous substrate and O2 consumption were assumed. The results agreed well with previous theoretical and experimental estimates for gradients in microbial colonies.