Development of Competence of Haemophilus influenzae

Publisher Website
Google Scholar
Abstract
Spencer, Hugh T. (The Johns Hopkins University School of Hygiene and Public Health, Baltimore, Md.), and Roger M. Herriott . Development of competence of Haemophilus influenzae . J. Bacteriol. 90: 911–920. 1965.—A chemically defined nongrowth medium was developed for the induction of competence of Haemophilus influenzae by a stepdown procedure. Cells grown logarithmically in Heart Infusion Broth became competent after being transferred to a medium which consisted of amino acids, sodium fumarate, and inorganic salts. Chloramphenicol (2 μg/ml) or l -valine (1 μg/ml) in the nongrowth medium inhibited development of competence. The inhibitory action of l -valine was reversed by comparable concentrations of l -isoleucine. Kinetic studies of the development of competence showed a variable capacity of competent cells to take up deoxyribonucleic acid and reaffirmed earlier findings that competence was not transmissible in H. influenzae . Addition of nicotinamide adenine dinucleotide, thiamine, calcium pantothenate, uracil, and hypoxanthine to the medium for competence resulted in a minimal growth medium in which reduced levels of competence were developed.

This publication has 20 references indexed in Scilit: