Study of membrane proteins from Microccus lysodeikticus using immunochemical methods]

Using immunoelectrophoresis, the antigenicity of various protein fractions of the Micrococcus lysodeikticus membranes was evaluated. It was shown that both the peripheral and integral membrane proteins possess the antigenic determinants. The antiserum exhausted by the M. lysodeikticus mebranes loses its ability to interact with intergral proteins, which are not solubilized by Triton X-100. It was thus assumed that the integral proteins are exposed on the membrane surface constantly or periodically and that there exist no proteins which are completely and permanently incorporated into the lipid bilayer. The respiratory chain of the M. lysodeikticus membrane is inhibited by membrane immunoglobulins by 50%. This is probably due to the presence in the membrane antiserum of antibodies specific to the respiratory chain enzymes. Evidence for this assumption can be derived from the fact that partially purified cytochrome b556 forms a precipitation zone with the membrane antiserum and that the activity of membrane NADH-dehydrogenase is inhibited by a monoserum against NADH-dehydrogenase.     

Staphylococcal DNA as a basis for classification

The genome characterization of the typing strains for all 13 species of the genus Staphylococcus, included into the Approval List of the Names of Bacterial (1980), is presented. The nucleotide composition of DNA (28-33% of GC) did not permit the differentiation between staphylococcal species, but some of the groups of these species could be differentiated by the size of their genome (0.6-1.6 X 10(9) daltons). Differences in the degree of similarity between the nucleotide sequences of the DNA of all species (5-6% of DNA homology) made it possible to suggest raising the genus Staphylococcus to the rank of the family Staphylococcaceae fam. nov. The hypothetical classification scheme of this family is presented for discussion.     

The use of a method for the electrophoretic typing by protein profiles of bacteria in the genus Acinetobacter for epidemiological diagnosis]

On the basis of data obtained by the biological characterization and electrophoretic typing of Acinetobacter sp. cultures by the spectra of membrane proteins epidemiological relationships, routes of transmission and specific features of the circulation of strains causing purulent inflammatory diseases have been determined.     

Analysis of strontium metabolism in humans on the basis of the Techa river data

Age and sex features of strontium metabolism have been analyzed based on studies of the population residing on the banks of the Techa river which was contaminated by fission products during the years 1949–1956. Measurements of ⁹⁰Sr body burden have been performed since 1974 using a whole-body counter, and these have made it possible to estimate age-specific long-term retention and elimination rates for men and women. Regarding the retention that correlated with the respective maturation ages, distinct sex differences have been observed for adolescents, whereas only postmenopausal women showed a sharp increase of their elimination rates. There were no differences concerning the reproductive ages. Our experimental findings have a clear physiological interpretation and can be used to develop metabolic models for bone-seeking radionuclides. Received: 22 September 1995 / Accepted in revised form: 10 October 1996     

Membrane protein spectra of staphylococci from a comparative physiological aspect]

Membrane protein spectra, obtained by electrophoresis in the system polyacrylamide gel--sodium dodecysolfate, were studied in 14 staphylococcal strains with different properties. The proteinograms of membranes were shown to be useful as an additional criterion in the identification of staphylococci. Fractions and their combination characteristic of all the strains and their separate groups were revealed in the protein spectra of staphylococcal membranes.     

Outer membrane proteins in the characterization of salmonellae of various origins

Outer membrane proteins have been studied in 76 Salmonella strains isolated from various sources and differing in their sensitivity to antibiotics, the presence of R-plasmids and a number of enzymatic properties. The outer membranes have been isolated by the modified method of L. W. Coulton and D. T. F. Wan. The study of the isolated proteins has been carried out by means of gel and disc electrophoresis in polyacrylamide gel with sodium dodecyl sulfate according to K. Weber and M. Osborn. The composition of the proteinograms thus obtained has revealed the presence of essential differences between hospital strains and cultures isolated from animals and from the environment in sporadic infections, as well as between strains belonging to different serovars. The possibility of using the characterization of outer membrane proteins of salmonellae in epidemiological investigations is discussed.