Aspartate Decarboxylation Encoded on the Plasmid in the Soy Sauce Lactic Acid Bacterium,Tetragenococcus halophilaD10

ABSTRACT In this study, we report the purification, initial structural characterization, and functional analysis of the molecular chaperone ClpB from the gram-positive, halophilic lactic acid bacterium Tetragenococcus halophilus. A recombinant T. halophilus ClpB (ClpB Tha ) was overexpressed in Escherichia coli and purified by affinity chromatography, hydroxyapatite chromatography, and gel filtration chromatography. As demonstrated by gel filtration chromatography, chemical cross-linking with glutaraldehyde, and electron microscopy, ClpB Tha forms a homohexameric single-ring structure in the presence of ATP under nonstress conditions. However, under stress conditions, such as high-temperature (>45°C) and high-salt concentrations (>1 M KCl), it dissociated into dimers and monomers, regardless of the presence of ATP. The hexameric ClpB Tha reactivated heat-aggregated proteins dependent upon the DnaK system from T. halophilus (KJE Tha ) and ATP. Interestingly, the mixture of dimer and monomer ClpB Tha , which was formed under stress conditions, protected substrate proteins from thermal inactivation and aggregation in a manner similar to those of general molecular chaperones. From these results, we hypothesize that ClpB Tha forms dimers and monomers to function as a holding chaperone under stress conditions, whereas it forms a hexamer ring to function as a disaggregating chaperone in cooperation with KJE Tha and ATP under poststress conditions.

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High efficacy bioconversion of starch to lactic acid using an amylolytic lactic acid bacterium isolated from Thai indigenous fermented rice noodles

Food Science and Biotechnology ◽

10.1007/s10068-014-0210-5 ◽

2014 ◽

Vol 23 (5) ◽

pp. 1541-1550 ◽

Cited By ~ 11

Author(s):

Apinun Kanpiengjai ◽

Wannisa Rieantrakoonchai ◽

Ronachai Pratanaphon ◽

Wasu Pathom-aree ◽

Saisamorn Lumyong ◽

...

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacterium ◽

High Efficacy

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Draft Genome Sequence of Enterococcus faecalis DD14, a Bacteriocinogenic Lactic Acid Bacterium with Anti-Clostridium Activity

Genome Announcements ◽

10.1128/genomea.00695-17 ◽

2017 ◽

Vol 5 (30) ◽

Cited By ~ 2

Author(s):

Yanath Belguesmia ◽

Valérie Leclère ◽

Matthieu Duban ◽

Eric Auclair ◽

Djamel Drider

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacterium ◽

Enterococcus Faecalis ◽

Genome Sequence ◽

Draft Genome ◽

Draft Genome Sequence ◽

Coding Sequences ◽

Content Type ◽

Gram Positive Bacteria ◽

Healthy Newborn

ABSTRACT We report the draft genome sequence of Enterococcus faecalis DD14, a strain isolated from meconium of a healthy newborn at Roubaix Hospital (France). The strain displayed antagonism against a set of Gram-positive bacteria through concomitant production of lactic acid and bacteriocin. The genome has a size of 2,893,365 bp and a 37.3% G+C ratio and is predicted to contain at least 2,755 coding sequences and 62 RNAs.

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