Putrescine production via the agmatine deiminase pathway increases the growth of Lactococcus lactis and causes the alkalinization of the culture medium

© 2014, Springer-Verlag Berlin Heidelberg. Lactococcus lactis is the most important starter culture organism used in the dairy industry. Although L. lactis species have been awarded Qualified Presumption of Safety status by the European Food Safety Authority, and Generally Regarded as Safe status by...

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Bibliographic Details
Authors: Río Lagar, Beatriz del, Linares, Daniel M., Ladero Losada, Víctor Manuel, Redruello, Begoña, Fernández García, María, Martín, M. Cruz, Álvarez González, Miguel Ángel
Format: article
Status:Versión aceptada para publicación
Publication Date:2015
Country:España
Institution:Consejo Superior de Investigaciones Científicas (CSIC)
Repository:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:dnet:digitalcsic_::57ad3e959d853af8e26bdb8cb1eeee51
Online Access:http://hdl.handle.net/10261/124805
Access Level:Open access
Keyword:Biogenic amines
Putrescine
Agmatine deiminase
AGDI cluster
Bacterial growth
Lactococcus lactis
Description
Summary:© 2014, Springer-Verlag Berlin Heidelberg. Lactococcus lactis is the most important starter culture organism used in the dairy industry. Although L. lactis species have been awarded Qualified Presumption of Safety status by the European Food Safety Authority, and Generally Regarded as Safe status by the US Food and Drug Administration, some strains can produce the biogenic amine putrescine. One such strain is L. lactis subsp. cremoris CECT 8666 (formerly L. lactis subsp. cremoris GE2-14), which was isolated from Genestoso cheese. This strain catabolizes agmatine to putrescine via the agmatine deiminase (AGDI) pathway, which involves the production of ATP and two ammonium ions. The present work shows that the availability of agmatine and its metabolization to putrescine allows for greater bacterial growth (in a biphasic pattern) and causes the alkalinization of the culture medium in a dose-dependent manner. The construction of a mutant lacking the AGDI cluster (L. lactis CECT 8666 Δagdi) confirmed the latter’s direct role in putrescine production, growth, and medium alkalinization. Alkalinization did not affect the putrescine production pattern and was not essential for increased bacterial growth.