Type

Journal Article

Authors

C Hill
R P Ross
S M Morgan
L O'Sullivan

Subjects

Microbiology

Topics
metabolism lactococcus lactis pharmacology drug effects bacterial proteins bacteriocins food technology enzymology lacticin 481 microbiology cheese biosynthesis dipeptidyl peptidases and tripeptidyl peptidases l lactate dehydrogenase

Elevated enzyme release from lactococcal starter cultures on exposure to the lantibiotic lacticin 481, produced by Lactococcus lactis DPC5552. (2002)

Abstract A Lactococcus lactis subsp. lactis strain (DPC5552), which causes the lysis of other lactococcal cultures, was isolated during a screening of raw milk samples for bacteriocin producers. Purification of the bacteriocin produced revealed that production of the lantibiotic, lacticin 481, was associated with the bacteriolytic capability of the strain. However, unlike bacteriocin-induced lysis observed with bacteriocins such as lacticin 3147 and lactococcins A, B, and M (where the target strain is killed), the DPC5552 supernatant gave rise to a situation whereby the target strain continued to grow (albeit at a lower rate) with simultaneous release of the intracellular enzymes lactate dehydrogenase (LDH) and post-proline dipeptidyl aminopeptidase (Pep X). In parallel experiments, 32 AU/ml of the inhibitory activity from L. lactis DPC5552 resulted in a 10- and 6-fold-higher LDH release after 5 h than that with 32 AU/ml of either lacticin 3147 or lactococcin A, B, and M. Laboratory-scale Cheddar cheese-making trials also demonstrated that lacticin 481-producing cultures induced the release of elevated levels of LDH from the starter L. lactis HP, without severely compromising its acid-producing capabilities. These results indicate that lacticin 481-producing strains may provide improved adjuncts for delivering lactococcal intracellular enzymes into the cheese matrix and, thus, improve cheese quality and flavor.
Collections Ireland -> Teagasc -> PubMed

Full list of authors on original publication

C Hill, R P Ross, S M Morgan, L O'Sullivan

Experts in our system

1
Colin Hill
University College Cork
Total Publications: 351
 
2
R Paul Ross
Teagasc
Total Publications: 441
 
3
Laurie O'Sullivan
Teagasc
Total Publications: 15