Protein H encoded by plasmid CloDF13 is involved in excretion of cloacin DF13.
AUTOR(ES)
Oudega, B
RESUMO
Excretion of cloacin DF13 was studied in Escherichia coli cells harboring different CloDF13 insertion and deletion mutant plasmids. Insertions of a transposon at position 9.8 or 11.5% of the CloDF13 plasmid blocked the expression of gene H and strongly reduced the specific excretion of cloacin DF13 into the culture medium, but had no effect on the production of cloacin DF13. Insertions in or deletions of regions of the CloDF13 DNA upstream the cloacin operon did not affect the excretion or production of the bacteriocin. Introduction of a CloDF13 plasmid that encodes for the gene H product in cells harboring a CloDF13 plasmid with an insertion in gene H stimulated the excretion of cloacin DF13 significantly in mitomycin C-induced and in noninduced cultures. Cloacin DF13 in cloacinogenic cells that did not produce the gene H protein was found to be about 90% located in the cytoplasm. In cells that did produce the gene H product, about 30% of the cloacin DF13 molecules were found in the cytoplasm, about 18% were found in the periplasm, about 2% were in the membranes, and about 50% were located in the culture supernatant. Cyclic AMP stimulated the production but not the excretion of cloacin DF13 in cells cultivated in the presence of glucose.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=216331Documentos Relacionados
- Production and excretion of cloacin DF13 by Escherichia coli harboring plasmid CloDF13.
- Transcription of bacteriocinogenic plasmid CloDF13 in vivo and in vitro: structure of the cloacin immunity operon.
- Methylation-dependent transcription controls plasmid replication of the CloDF13 cop-1(Ts) mutant.
- Changes in protein synthesis on mitomycin C induction of wild-type and mutant CloDF13 plasmids.
- Clo DF13 plasmid deoxyribonucleic acid-directed in vitro synthesis of biologically active cloacin DF13 and clo DF13 immunity protein.