9.A.7 The Lactococcin 972 Immunity Protein (LactococcinIP) Family
A single sequenced protein comprises the lactococcin 972 family (1.C.37.1.1). This protein is plasmid-encoded in Lactococcus lactis. The mature protein is 66 aas long, but it is exported as a 91-residue precursor via the Sec (PSII) protein secretory pathway. It is cleaved extracellularly. It is encoded within a 2 cistron operon that also encodes a 563-residue immunity protein with 7 putative TMSs. Two transcripts are made: one encompasses the whole operon and is synthesized during the exponential growth phase; the other includes only the bacteriocin structural gene and is made both during the exponential and stationary growth phases. Distant homologues are found in other firmicutes.
Class IIc bacteriocin, Lactococcin 972 immunity protein
Lactococcin 972 Immunity Protein of Lactococcus lactis
Uncharacterized bacteriocin-associated integral membrane protein of 659 aas and 8 TMSs.
UP of Lactobacillus jensenii
DUF1430 domain protein of 735 aas and 8 TMSs.
DUF1430 protein of Bacillus subtilis
Uncharacterized protein of 567 aas and 7 TMSs in a 4 + 5 TMS arrangement. This protein may be N-terminally truncated.
UP of Corynebacterium oculi
Uncharacterized protein of 719 aas annd 8 TMSs in a 1 + 4 + 3 TMS arrangement.
UP of Mogibacterium diversum
Uncharacterized protein of 732 aas and 8 TMSs in a 1 + 4 + 3 TMS arrangement.
UP of Macrococcus caseolyticus
Uncharacterized protein of 689 aas and 8 TMSs in a 1 + 4 + 3 TMS arrangement.
UP of Nocardiopsis dassonvillei