Abstract
Two distinct R mutants of pneumococcus type VIIIS have been described in which the mutations leading to loss of type VIII polysaccharide production are non-allelic. A DNA extract prepared from either R strain restores the capacity to produce type VIII polysaccharide in the other strain. Autologous extracts are inert in this respect. DNA extracts from pneumococcus type IIS when applied to the two R mutants consistently yielded a high proportion of cells transformed to type VIIIS and relatively small numbers of type IIS cells. When extracts prepared from other encapsulated pneumococci, types IS, VIIS, XIVS, and XVIIIS, were applied to R mutant VIII-R1, a mixture of type VIIIS cells and cells corresponding to the type of the donor appeared, although the proportion of type VIIIS cells was not uniformly in excess. The same extracts applied to the second R mutant, VIII-R13, yielded transformed cells of the type of the donor only, or else transformation did not occur. Transforming extracts of a strain of pneumococcus type IIIS gave rise only to type IIIS pneumococci when applied to either strain. Type VIIIS pneumococci were never recovered from such interactions.
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Selected References
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- Avery O. T., Macleod C. M., McCarty M. STUDIES ON THE CHEMICAL NATURE OF THE SUBSTANCE INDUCING TRANSFORMATION OF PNEUMOCOCCAL TYPES : INDUCTION OF TRANSFORMATION BY A DESOXYRIBONUCLEIC ACID FRACTION ISOLATED FROM PNEUMOCOCCUS TYPE III. J Exp Med. 1944 Feb 1;79(2):137–158. doi: 10.1084/jem.79.2.137. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Macleod C. M., Krauss M. R. STEPWISE INTRATYPE TRANSFORMATION OF PNEUMOCOCCUS FROM R TO S BY WAY OF A VARIANT INTERMEDIATE IN CAPSULAR POLYSACCHARIDE PRODUCTION. J Exp Med. 1947 Nov 30;86(6):439–452. doi: 10.1084/jem.86.6.439. [DOI] [PMC free article] [PubMed] [Google Scholar]
- STOCKER B. A. Transduction of flagellar characters in Salmonella. J Gen Microbiol. 1953 Dec;9(3):410–433. doi: 10.1099/00221287-9-3-410. [DOI] [PubMed] [Google Scholar]