Regulation of nisin biosynthesis and immunity in Lactococcus lactis 6F3

Abstract

The biosynthetic genes of the nisin-producing strain Lactococcus lactis 6F3 are organized in an operon-like structure starting with the structural gene nisA followed by the genes nisB, nisT, and nisC, which are probably involved in chemical modification and secretion of the prepeptide (G. Engelke, Z. Gutowski-Eckel, M. Hammelmann, and K.-D. Entian, Appi. Environ. Microbiol. 58:3730-3743, 1992). Subcloning of an adjacent 5-kb downstream region revealed additional genes involved in nisin biosynthesis. The gene nisI, which encodes a lipoprotein, causes increased immunity after its transformation into nisin-sensitive L. lactis MG1614. It is followed by the gene nisP, coding for a subtilisin-like serine protease possibly involved in processing of the secreted leader peptide. Adjacent to the 3' end of nisP the genes nisR and nisK were identified, coding for a regulatory protein and a histidine kinase, showing marked similarities to members of the OmpRIEnvZ-like subgroup of two-component regulatory systems. The deduced amino acid sequences of nisR and nisK exhibit marked similarities to SpaR and SpaK, which were recently identified as the response regulator and the corresponding histidine kinase of subtilin biosynthesis. By using antibodies directed against the nisin prepeptide and the NisB protein, respectively, we could show that nisin biosynthesis is regulated by the expression of its structural and biosynthetic genes. Prenisin expression starts in the exponential growth phase and precedes that of the NisB protein by approximately 30 min. Both proteins are expressed to a maximum in the stationary growth phase.

Lantibiotics: structure, biosynthesis and mode of action

“…An essential role has been proposed for NisB in nisin maturation, as it has been reported that mature nisin is not secreted before NisB can be detected. The synthesis of SpaB is also strictly regulated, but conversely, occurs only when mature subtilin is detected outside the cell [110]. It has been proposed that the dehydration of serine and threonine is catalysed by the LanB enzymes, although experimental evidence is lacking.…”

“…The phosphoryl group is then transferred to a conserved Asp of the corresponding intracellular RR which is generally a transcriptional activator. Genes encoding both HPKs (LanK) and RRs (LanR) have been identi¢ed in the gene clusters of nisin [110], subtilin [139], SA-FF22 [79] and mersacidin [121]. In the case of nisin and subtilin, inactivation studies con¢rmed that these genes were essential for production.…”

Lipid-free NisI: interaction with nisin and contribution to nisin immunity via secretion

“…The membrane of L. lactis is sensitive to nisin. For membrane protection, nisin producers synthesize a com-plex immunity system consisting of four polypeptides: the membrane-bound lipoprotein NisI, and an ABC translocator including two integral membrane proteins, NisE and NisG, and cytoplasmic NisF [8][9][10][11][12][13]. Both NisI and NisF/E/G play important roles in nisin immunity.…”

Nisin Z, Mutant Nisin Z and Lacticin 481 Interactions with Anionic Lipids Correlate with Antimicrobial Activity

“…Five of these dehydrated residues subse-qLtently link their C/' atom to the sulfur atom of five cysteine residucs in a specific way, resulting in the characteristic (/I-meth-y1)lanthionine rings. These modification reactions are probably enzymc-catalyzed and likely candidates for these enzymatic reactions have been proposed (Engelke et al, 1992(Engelke et al, , 1994Kuipers el al., 1993a;Van der Meer et al, 1993).…”

“…The organization of the nisin gene cluster nisAHTCIPRK- FEG (Buchman et al 1988; Kaletta and Entian, 1989;Engellte et al, 1992Engellte et al, , 1994; Van der Meer et al, 1993;Kuipcrs et al, 1993 a ;Sicgers and Entian, 1995), the function of thc encoded proteins in biosynthesis (Engelke et al 1992(Engelke et al , 1994Van der Meer et al, 1993;Kuipers et al, 1993b), nisin precursor secretion (Van der Meer et al, 1993) and immunity (Kuipers et al, 1993a,b;Engelkc et al, 1994;Siegers and Entian, 1995), and the way by which the expression of the nisin genes is regulated (Kuipers et al, unpublished results), have been studied in detail. In addition, protein engineering studies of nisin have been performed to gain insight into the requirements for the complicated biosynthesis of nisin and as attempts to improve relevant properties of nisin (Kuipers et al, 1992; Van der Meer et al, 1994;Rollema et al, 1995).…”