ABSTRACT
In Drosophila the UV sensitivity at the zygote stage and PR ability of damage induced by UV irradiation at 290-380 nm are heritable characters. The heritability of those characters is matroclinal. Resistance to UV irradiation dominates over sensitivity, and high PR ability is dominant over low. These characters are not associated with the pleiotropic action of any of the genes in question.
Subject(s)
Drosophila/radiation effects , Genes , Animals , Dose-Response Relationship, Radiation , Drosophila/genetics , Embryo, Nonmammalian/radiation effects , Female , Light , Ultraviolet Rays , Zygote/radiation effectsABSTRACT
In a population of the productive Bacillus subtilis strain the production of alpha-amylase differentiates at the cell level. Individual cells in the population were analyzed and the production of isolates was tested. The mean specific activity of alpha-amylase in the productive group after the isolation was 5.0 U/mg dry substance and in the nonproductive group 1.5 U/mg dry substance. This ratio remained unchanged during long-term observations and after repeated transfers. In selected strains of both groups the specific growth rate was determined in a synthetic medium containing various amounts of casein hydrolyzate. The detected differences in the growth rate between the productive and the nonproductive clones are determined by amino acid concentration.
Subject(s)
Amylases/biosynthesis , Bacillus subtilis/enzymology , alpha-Amylases/biosynthesis , Bacillus subtilis/growth & development , Clone Cells , Time FactorsABSTRACT
Thermus flavus and T. ruber grew optimally at 75 and 60 degrees C, respectively, but transport of monosaccharides (D-quinovose) and amino acids (2-aminoisobutyric acid) had optima about 20 degree C lower. Both transports were active, inhibited by 2,4-dinitrophenol but hardly at all by uranyl(2+) ions. Several transport systems are apparently involved with each class of compounds. Preincubation with glucose curtailed subsequent transport severely. Practical cessation of transport below 35 degrees C may be associated with the rather uniform composition of membrane lipids where iso- and anteiso-C15 and C17 acids are practically the only components.