DETERMINATION AND COMPARATIVE-ANALYSIS OF NUCLEOTIDE-SEQUENCES IN FRAGMENTS OF THE MINIREPLICON OF P1414 CRYPTIC PLASMID FROM THE BACILLUS-SUBTILIS SOIL STRAIN

Nucleotide sequences of two minireplicon fragments of the p1414 crypti c plasmid of Bacillus subtilis were determined. The fragments correspo nded to the region containing ori(+) and the gene coding for Rep prote in. Comparing sequences of the fragments with corresponding sequences of other ss(+) plasmids suggested that ori(+) of p1414 belongs to the family of endogenous cryptic B. subtilis plasmids, which form an indiv idual, closely related subgroup in the group of ori(+) sequences of th e pC194 type. It was found that the amino acid sequence of a conservat ive FLTLTV motif located, together with its flanking sequences, at the N ends of Rep proteins encoded by different ss(+) plasmids, is simila r to those of several transmembrane proteins and signal peptides. Thes e results, together with computer data on predicting the secondary and tertiary structure of the N-terminal domain of the p1414 Rep protein, suggest that the domain can serve as a ''membrane anchor'' during pla smid replication.