Influence of sugars and pH on the citrate metabolism of different lactic acid bacteria strains in a synthetic wine matrix

2019 ◽  
Vol 127 (5) ◽  
pp. 1490-1500 ◽  
Author(s):  
N. Pretorius ◽  
L. Engelbrecht ◽  
M. Du Toit
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Citrate Metabolism ◽  
Wine Matrix

scholarly journals CitI, a Transcription Factor Involved in Regulation of Citrate Metabolism in Lactic Acid Bacteria

2005 ◽  
Vol 187 (15) ◽  
pp. 5146-5155 ◽  
Author(s):  
Mauricio G. Martin ◽  
Christian Magni ◽  
Diego de Mendoza ◽  
Paloma López
Keyword(s):  
Transcription Factor ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Rna Polymerase ◽  
Metabolic Pathways ◽  
Signal Propagation ◽  
Metabolic Energy ◽  
Citrate Metabolism ◽  
Divergent Gene ◽  
Dna Binding Affinity

ABSTRACT A large variety of lactic acid bacteria (LAB) can utilize citrate under fermentative conditions. Although much information concerning the metabolic pathways leading to citrate utilization by LAB has been gathered, the mechanisms regulating these pathways are obscure. In Weissella paramesenteroides (formerly called Leuconostoc paramesenteroides), transcription of the citMDEFCGRP citrate operon and the upstream divergent gene citI is induced by the presence of citrate in the medium. Although genetic experiments have suggested that CitI is a transcriptional activator whose activity can be modulated in response to citrate availability, specific details of the interaction between CitI and DNA remained unknown. In this study, we show that CitI recognizes two A+T-rich operator sites located between citI and citM and that the DNA-binding affinity of CitI is increased by citrate. Subsequently, this citrate signal propagation leads to the activation of the cit operon through an enhanced recruitment of RNA polymerase to its promoters. Our results indicate that the control of CitI by the cellular pools of citrate provides a mechanism for sensing the availability of citrate and adjusting the expression of the cit operon accordingly. In addition, this is the first reported example of a transcription factor directly functioning as a citrate-activated switch allowing the cell to optimize the generation of metabolic energy.

scholarly journals Selection of Lactic Acid Bacteria Isolated from Fresh Fruits and Vegetables Based on Their Antimicrobial and Enzymatic Activities

Foods ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 1399
Author(s):  
José Rafael Linares-Morales ◽  
Guillermo Eduardo Cuellar-Nevárez ◽  
Blanca Estela Rivera-Chavira ◽  
Néstor Gutiérrez-Méndez ◽  
Samuel Bernardo Pérez-Vega ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Fruits And Vegetables ◽  
Enzymatic Activities ◽  
Bioactive Metabolites ◽  
Gram Positive ◽  
Citrate Metabolism ◽  
Mold And Yeast ◽  
De Man

Lactic acid bacteria (LAB) are an important source of bioactive metabolites and enzymes. LAB isolates from fresh vegetable sources were evaluated to determine their antimicrobial, enzymatic, and adhesion activities. A saline solution from the rinse of each sample was inoculated in De Man, Rogosa and Sharpe Agar (MRS Agar) for isolates recovery. Antimicrobial activity of cell-free supernatants from presumptive LAB isolates was evaluated by microtitration against Gram-positive, Gram-negative, LAB, mold, and yeast strains. Protease, lipase, amylase, citrate metabolism and adhesion activities were also evaluated. Data were grouped using cluster analysis, with 85% of similarity. A total of 76 LAB isolates were recovered, and 13 clusters were formed based on growth inhibition of the tested microorganisms. One cluster had antimicrobial activity against Gram-positive bacteria, molds and yeasts. Several LAB strains, PIM4, ELO8, PIM5 and CAL14 strongly inhibited the growth of L. monocytogenes and JAV15 and TOV9 strongly inhibited the growth of F. oxysporum. Based on enzymatic activities, 5 clusters were formed. Seven isolates hydrolyzed starch, 46 proteins, 14 lipids, and 36 metabolized citrate. LAB isolates with the best activities were molecularly identified as Leuconostoc mesenteroides, Enterococcus mundtii and Enterococcus faecium. Overall, LAB isolated from vegetables showed potential technological applications and should be further evaluated.

Induction of some enzymes of citrate metabolism inLeuconostoc lactisand other heterofermentative lactic acid bacteria

1981 ◽  
Vol 48 (3) ◽  
pp. 497-502 ◽  
Author(s):  
Dervla Mellerick ◽  
Timothy M. Cogan
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Acetolactate Synthase ◽  
Citrate Metabolism ◽  
Citrate Lyase ◽  
Leuconostoc Lactis

SummaryCitrate stimulated growth, totally induced citrate lyase, partly induced acetolactate synthase activity and partly repressed both diacetyl and acetoin reductases inLeuconostoc lactisNCW1. Similar results were obtained with 2 other leuconostocs and a heterofermentative lactobacillus. In 2 of the 3 leuconostocs tested, diacetyl reductase and acetoin reductase were NADPH specific, while in the 2 heterofermentative lactobacilli, they were NADH specific.

Lactic acid bacteria and yeasts in kefir grains and kefir made from them

2002 ◽  
Vol 28 (1) ◽  
pp. 1-6 ◽  
Author(s):  
E Simova ◽  
D Beshkova ◽  
A Angelov ◽  
Ts Hristozova ◽  
G Frengova ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Kefir Grains

Development of biotechnology for gluten-free sourdough bakery products with a new microbial composition

2020 ◽  
Vol 29 (12) ◽  
pp. 59-63
Author(s):  
O.I. Parakhina ◽  
◽  
M.N. Lokachuk ◽  
L.I. Kuznetsova ◽  
E.N. Pavlovskaya ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Starter Culture ◽  
Comparative Assessment ◽  
Starter Cultures ◽  
Bakery Products ◽  
Gluten Free ◽  
Microbial Composition ◽  
Fermentative Activity ◽  
Theoretical Foundations

The research was carried out within the framework of the theme of state assignment № 0593–2019–0008 «To develop theoretical foundations for creating composite mixtures for bakery products using physical methods of exposure that ensure homogeneity, stability of mixtures and bioavailability of nutrients, to optimize diets population of Russia». The data on the species belonging of new strains of lactic acid bacteria and yeast isolated from samples of good quality gluten-free starter cultures are presented. A comparative assessment of the antagonistic and acid-forming activity of strains of lactic acid bacteria and the fermentative activity of yeast was carried out. The composition of microbial compositions from selected strains of LAB and yeast was developed. The influence of the starter culture on the new microbial composition on the physicochemical, organoleptic indicators of the bread quality and resistance to mold and ropy-disease was investigated.

Cryopreservation to be a progressive method for keeping up valuable strains of lactic acid bacteria and yeasts

2014 ◽  
pp. 112-119 ◽  
Author(s):  
O.A. Savkina ◽  
◽  
G.V. Ternovskoi ◽  
M.N. Lokachuk ◽  
E.N. Pavlovskaya ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Progressive Method

In vitro adhesion of lactic acid bacteria and bifidobacteria to Caco-2P and IEC-18 cells

2005 ◽  
Vol 34 (1) ◽  
pp. 91-99 ◽  
Author(s):  
K. Szekér ◽  
J. Beczner ◽  
A. Halász ◽  
Á. Mayer ◽  
J.M. Rezessy-Szabó ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
In Vitro Adhesion
Sign in / Sign up

Export Citation Format

Share Document