A plasmid in Streptococcus pneumoniae

Plasmid deoxyribonucleic acid has been detected in three related laboratory strains of Streptococcus pneumoniae. Strains D39S, R36, and R36NC each contain a minimum of two copies per cell of a 2.0-megadalton plasmid (pDP1). A plasmid twice as large as this smaller one is also present in much lower quantity in these strains, but neither plasmid is present in four strains related to these or in a drug-resistant clinical isolate from Paris. The plasmid yield was not amplified in the presence of chloramphenicol. No phenotype has been correlated with the presence of pDP1, which has existed in strains carried for many years in laboratory collections.

[1]  A. Kleinschmidt.  [125] Monolayer techniques in electron microscopy of nucleic acid molecules , 1968 .

[2]  A. Ravin.  RECIPROCAL CAPSULAR TRANSFORMATIONS OF PNEUMOCOCCI , 1959, Journal of bacteriology.

[3]  W. V. Shaw,et al.  Chloramphenicol Resistance in Streptococcus pneumoniae: Enzymatic Acetylation and Possible Plasmid Linkage , 1978, Antimicrobial Agents and Chemotherapy.

[4]  R. Radloff,et al.  A dye-buoyant-density method for the detection and isolation of closed circular duplex DNA: the closed circular DNA in HeLa cells. , 1967, Proceedings of the National Academy of Sciences of the United States of America.

[5]  D. Helinski,et al.  Circular DNA forms of colicinogenic factors E1, E2 and E3 from Escherichia coli. , 1968, Journal of molecular biology.

[6]  M. Neuberger,et al.  Membrane location of a deoxyribonuclease implicated in the genetic transformation of Diplococcus pneumoniae , 1975, Journal of bacteriology.

[7]  D. J. Leblanc,et al.  Transformation of Streptococcus sanguis Challis by plasmid deoxyribonucleic acid from Streptococcus faecalis , 1976, Journal of bacteriology.

[8]  L. Mindich.  Bacteriocins of Diplococcus pneumoniae I. Antagonistic Relationships and Genetic Transformations , 1966, Journal of bacteriology.

[9]  R. Porter,et al.  Characterization of some pneumococcal bacteriophages , 1976, Journal of virology.

[10]  H. Koornhof,et al.  Emergence of multiply resistant pneumococci. , 1978, The New England journal of medicine.

[11]  C. Macleod,et al.  STEPWISE INTRATYPE TRANSFORMATION OF PNEUMOCOCCUS FROM R TO S BY WAY OF A VARIANT INTERMEDIATE IN CAPSULAR POLYSACCHARIDE PRODUCTION , 1947, The Journal of experimental medicine.

[12]  F. Studier,et al.  Analysis of restriction fragments of T7 DNA and determination of molecular weights by electrophoresis in neutral and alkaline gels. , 1977, Journal of molecular biology.

[13]  S. Lacks,et al.  Complementary specificity of restriction endonucleases of Diplococcus pneumoniae with respect to DNA methylation. , 1977, Journal of molecular biology.

[14]  R. Espejo,et al.  Properties of bacteriophage PM2: a lipid-containing bacterial virus. , 1968, Virology.

[15]  K. Timmis,et al.  Replication Region Fragments Cloned from Flac+ Are Identical to EcoRI Fragment f5 of F , 1976, Journal of bacteriology.

[16]  R. W. Davis,et al.  Studies on the cleavage of bacteriophage lambda DNA with EcoRI Restriction endonuclease. , 1975, Journal of molecular biology.