PubMed Health⌕ Search

Biomedical subjects

R M COLE

Publications and source records attributed to R M COLE.

At least 19 recordsLinked to original sources
PubMed1964

CELL WALL REPLICATION IN SALMONELLA TYPHOSA.

Changes in the fluorescence of the cell wall of Salmonella typhosa (TY2 W) were studied during growth after direct labeling with fluorescein conjugated homologous or "anti-O" globulins. Fluorescence decreased evenly with culture growth and cell division, but the addition ofchloramphenicol resulted in large, nondividing cells that showed increasing interruption of fluorescence of the wall marker. The process thus differs from the equatorial origin and discrete hemispherical addition of new wall previously described in Streptococcus pyogenes. These findings, in addition to demonstrating the formation of new wall in the presence of chloramphenicol, appear consistent only with the concept that wall replication in the salmonellas occurs by means of diffuse intercalation of new materials among old.

Cell Biology↗
PubMed1963

STREPTOCOCCAL M ANTIGEN LOCATION AND SYNTHESIS, STUDIED BY IMMUNOFLUORESCENCE.

Streptococcal M protein has been studied directly in the intact streptococcal cell by specific immunofluorescence. By this method, it can be seen to be concentrated in or on the cell wall, but cannot be detected in the capsule. The lack of type-specific (but not group-specific) immunofluorescence after trypsinization; and the inhibition of group-specific immunofluorescence by unlabeled type-specific antibody, are observations most compatible with a location of the M antigen determinants on the cell surface superficial to the group antigen. M antigen is not "resynthesized" after trypsinization of living cells, but appears anew only at sites of new cell wall growth. A limited amount of such growth, leading sometimes to detectable amounts of M in the gross, can take place in deficient media without detectable increases in optical density of the cell population.

Animals↗
PubMed1963

Studiey on the mechanism of the long chain phenomenon of group A streptococci.

The formation and destruction of long chains by growth of Group A streptococci in the presence of type-specific antibody have been studied with the fluorescent antibody technique. Long chain formation has been shown to depend on the presence of free antibody during the growth of the bacteria. Destruction of long chains has been shown to depend on the continued growth and division of the bacteria in the absence of free antibody. Univalent antibody fragments formed by proteolytic digestion of antibody globulin have been shown to have the combining properties of untreated antibody but do not result in the production of long chains. A model involving end-to-end agglutination during growth of Group A streptococci has been presented to explain the mechanism of production of long chains by growth of Group A streptococci in the presence of type-specific antibody.

Antibodies↗
PubMed1962

Cell wall replication in Streptococcus pyogenes.

Group A streptococci (Streptococcus pyogenes) of several different serological types were grown in fluorescein-labeled homologous type or group-specific globulins, thereby labeling the antigen-containing cell walls. Specific precipitation or inhibition of the labeled antibody, followed by continued incubation and examination at intervals by ultraviolet, phase, and dark-field microscopy, showed that new cell wall was then nonfluorescent. These nonfluorescent portions were differentiated by a reverse technique of culture in unlabeled globulin, followed by antibody precipitation, further growth, and fluorescent-antibody staining. This technique of differential labeling of cell wall has permitted following, for the first time in a living system, the fate of cell wall formed at different times. The results suggest that cell wall synthesis in actively growing cultures usually occurs simultaneously at at least two sites per coccus, each site representing stages in successive divisions, and that cell wall growth in Streptococcus pyogenes is not by diffuse intercalation with old wall, but is initiated at and extends both peripherally and centripetally from the coccal equator.

Cell Division↗
PubMed1962

Time and concentration relationships in the long-chain reaction of group A streptococci in homologous antiserum and an improved method for evaluation of test results.

Hahn, Jerome J. (National Institutes of Health, Bethesda, Md.) and Roger M. Cole. Time and concentration relationships in the long-chain reaction of group A streptococci in homologous antiserum and an improved method for evaluation of test results. J. Bacteriol. 83:85-96. 1962-We have described a statistically controlled method for evaluating the long chain reaction of group A streptococci grown in homologous antisera. The method is based on the chi-square analysis of the frequency distribution of chain lengths found in test and control sera, and is called the Size-Class Frequency method. Useful tables for rapid application of the method are presented. It is reproducible, and is simpler, more rapid, and more sensitive than the previously described method. Using this method, we have shown that the long-chain reaction reaches a maximum and then declines with time of incubation. The time at which the maximal response and height are attained depends directly on the initial antibody concentration and inversely on the initial antigen concentration. The inter-relationships of time, antibody concentration, total number of cocci, total number of chains, and long-chain frequency (or chain length) are presented in the discussion.In view of the findings reported here, we suggest a re-evaluation of possible methods of "dechaining" or "chaining" among group A streptococci. Present evidence appears inadequate to explain the long-chain reaction on the basis of inhibition of a single enzyme.

Humans↗
PubMed1960

Preparation and antigenicity of M protein released from group A, type 1 streptococcal cell walls by phage-associated lysin.

The lysis of Group A type 1 streptococcal cell walls by phage-associated lysin has been described. In the preparation of lysin, a new semisynthetic non-protein media to support growth of the propagating strain of Group C streptococci was employed. Following lysis of the cell walls, the resulting digest was partially purified by ion-exchange chromatography and ammonium sulfate precipitation. In addition to M protein, the resulting preparation (called lysin M protein) contained the group-specific carbohydrate and the T protein-but did not contain antigens, detectable by precipitin tests, which cross-reacted with absorbed heterologous group or type antisera. Capillary precipitin reactions between the lysin M protein and type-specific antiserum did not occur in the presence of high ionic strength buffers; these buffers did not similarly affect precipitin reactions of acid M protein. Type 1 lysin M protein is shown to be a good antigen. A total of 1.5 mg. injected intradermally in saline produced bactericidal antibody in eight of nine rabbits; when injected in adjuvant in one rabbit, protective serum antibodies developed. Streptococci grown in sera from seven of nine rabbits immunized with lysin M protein demonstrated significantly longer chains than when grown in normal rabbit serum. Antibody as demonstrated by each of these three tests was shown to be type-specific. No local or systemic toxicity was noted following intradermal injection in rabbits of lysin M protein.

Animals↗