Cloning in Streptococcus pneumoniae of the gene for DpnII DNA methylase

Journal Article · Thu Mar 01 00:00:00 EST 1984 · J. Bacteriol.; (United States)

OSTI ID:5932638

Lacks, S A; Springhorn, S S

The gene coding for the pneumococcal DNA adenine methylase that recognizes the sequence 5'-GATC-3' was cloned in a strain of Streptococcus pneumoniae that lacked both restriction endonucleases DpnI and DpnII. The gene was cloned as a 3.7-kilobase fragment of chromosomal DNA from a DpnII-containing strain inserted in both possible orientations in the multicopy plasmid vector pMP5 to give recombinant plasmids pMP8 and pMP10. Recombinant plasmids were selected by their resistance to DpnII cleavage. Cells carrying the recombinant plasmids modified phage in vivo so that it was restricted by DpnI- but not DpnII-containing hosts. They also showed levels of DNA methylase activity five times higher than that in cells of the original DpnII strain. No DpnII activity was observed in the clones; therefore, it was concluded that the insert did not contain an intact DpnII endonuclease gene and that methylation of host DNA did not turn on a latent form of the gene. 16 references, 1 figure, 2 tables.

• Research Organization: Brookhaven National Lab., Upton, NY
• OSTI ID: 5932638
• Journal Information: J. Bacteriol.; (United States), Vol. 157:3
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
ENDONUCLEASES
ENZYME ACTIVITY
GENES
CLONING
CLEAVAGE
DNA
DNA SEQUENCING
EXPERIMENTAL DATA
PLASMIDS
STREPTOCOCCUS
BACTERIA
CELL CONSTITUENTS
CRYSTAL STRUCTURE
DATA
DNA-ASE
ENZYMES
ESTERASES
HYDROLASES
INFORMATION
MICROORGANISMS
MICROSTRUCTURE
NUCLEIC ACIDS
NUMERICAL DATA
ORGANIC COMPOUNDS
PHOSPHODIESTERASES
STRUCTURAL CHEMICAL ANALYSIS
550400* - Genetics