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.


TC#NameOrganismal TypeExample

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


TC#NameOrganismal TypeExample

TC#NameOrganismal TypeExample