Direct Selection for P1-Sensitive Mutants of Enteric Bacteria

Temperature-sensitive mutants of bioluminescent bacteria.

Mutants of a marine luminous bacterium, in which the ability to emit light is conditional upon temperature, have been isolated. The mutants obtained fall into three classes, which are readily distinguishable by both in vivo and in vitro criteria. In one class an altered, more temperature-sensitive luciferase is produced; in a second, the luciferase is actually not produced at the higher tempera...

Expansion of the host range of coliphage P1 and gene transfer from enteric bacteria to other gram-negative bacteria.

The bacterial host range of coliphage P1 was extented by using the heat-inducible phage P1clr100KM. A gene for kanamycin resistance was transferred from Escherichia coli to members of the family Enterobacteriaceae and some other genera of gram-negative bacteria. P1 phage was produced by thermal induction from the lysogens of all these kanamycin-resistant bacteria except some strains.

Enteric Bacteria

Biochemical confirmation of salmonellae by conventional tube methods usually requires 2 to 3 days of incubation time preceded by preparation of tubed media and transfer of cultures. The principles of heavy inocula and increased substrate concentrations have been used by Sanders et al. (1) to speed up reaction times and thus reduce the time necessary in the laboratory for analysis. To characteri...

Glycogen of enteric bacteria.

In the course of an investigation of the use of infrared spectrophotometry for bacterial identification (Stevenson and Bolduan, 1952; Levine et al., 1953b), it has been found that a characteristic set of absorption bands appears in the spectra of Enterobacteriaceae and other bacteria under certain cultural conditions. Since this set of bands is common to many organisms, it is important in ident...

Isolation of Pre-Adaptive Mutants in Bacteria by Sib Selection.