The invention relates to a process for the production of L-amino acids, in particular L-threonine, in which the following steps are carried out: a) fermentation of the microorganisms of the family Enterobacteriaceae producing the desired L-amino acid, in which the aceA gene or nucleotide sequences coding therefor are attenuated, in particular are switched off; b) enrichment of the L-amino acid in the medium or in the cells of the bacteria; and c) isolation of the L-amino acid.

,Using the SHIME (an in vitro simulator of the human gut microbiome) we studied changes in the gut metabolome that occurred in response to the administration of the Laticaseibacillus rhamnosus strain GG (LGG). Using fecal inoculum from three healthy human donors, reactors were established representing three colonic regions and both the luminal and mucosal microbiome in those regions. Samples were collected before, during, and after inoculation of the reactors with LGG.,This dataset includes untargeted metabolomics data. Shallow shotgun metagenomic sequencing data can be found in the NCBI Sequence Read Archive associated with BioProject PRJNA893635 : https://www.ncbi.nlm.nih.gov/bioproject/PRJNA893635.,Resources in this dataset:,

The invention relates to a process for the fermentative preparation of L-amino acids, in particular L-threonine, in which the following steps are carried out: a) fermentation of the microorganisms of the Enterobacteriaceae family which produce the desired L-amino acid and in which the rseB gene or nucleotide sequences which code for it are enhanced, in particular over-expressed, b) concentration of the desired L-amino acid in the medium or in the cells of the bacteria, and c) isolation of the desired L-amino acid

Background The metallo-β-lactamases are Zn(II)-containing enzymes that hydrolyze the β-lactam bond in penicillins, cephalosporins, and carbapenems and are involved in bacterial antibiotic resistance. There are at least 20 distinct organisms that produce a metallo-β-lactamase, and these enzymes have been extensively studied using X-ray crystallographic, computational, kinetic, and inhibition studies; however, much is still unknown about how substrates bind and the catalytic mechanism. In an effort to probe substrate binding to metallo-β-lactamase L1 from Stenotrophomonas maltophilia, nine site-directed mutants of L1 were prepared and characterized using metal analyses, CD spectroscopy, and pre-steady state and steady state kinetics. Results Site-directed mutations were generated of amino acids previously predicted to be important in substrate binding. Steady-state kinetic studies using the mutant enzymes and 9 different substrates demonstrated varying Km and kcat values for the different enzymes and substrates and that no direct correlation between Km and the effect of the mutation on substrate binding could be drawn. Stopped-flow fluorescence studies using nitrocefin as the substrate showed that only the S224D and Y228A mutants exhibited weaker nitrocefin binding. Conclusions The data presented herein indicate that Ser224, Ile164, Phe158, Tyr228, and Asn233 are not essential for tight binding of substrate to metallo-β-lactamase L1. The results in this work also show that Km values are not reliable for showing substrate binding, and there is no correlation between substrate binding and the amount of reaction intermediate formed during the reaction. This work represents the first experimental testing of one of the computational models of the metallo-β-lactamases.

Acid-tolerant homolactic bacteria isolated from corn steep water capable of generating a solution including at least 50 g/L lactate at a final incubation pH of 4.3 or lower, wherein the lactate has an optical purity of at least 50%.

Background Seeds of the legume plant Lathyrus sativus, which is grown in arid and semi arid tropical regions, contain Diamino Propionic acid (DAP). DAP is a neurotoxin, which, when consumed, causes a disease called Lathyrism. Lathryrism may manifest as Neurolathyrism or Osteolathyrism, in which the nervous system, and bone formation respectively, are affected. DAP ammonia lyase is produced by a few microorganisms such as Salmonella typhi, Salmonella typhimurium and Pseudomonas, and is capable of detoxifying DAP. Results S. typhimurium PU011, a non-virulent bacterial strain isolated in our lab, was found to produce DAP ammonia lyase enzyme when grown in minimal medium containing DAP. There was a direct correlation between biomass yield and enzyme activity, until 16 h post inoculation in minimal medium containing DAP. Following ammonium sulphate precipitation and passing through Sephadex G100, CM-Sephadex and DEAE-Sephacel for crude enzyme extract preparation, about 68-fold enzyme purity was obtained. The purified enzyme gave maximum activity at pH 8.0 and was stable up to 45 degrees C. The Km value for the substrate was found to be 0.685mM, calculated from a Line Weaver Burk plot. Conclusion A new bacterial strain, S.typhimurium PU 011, which is capable of producing DAP ammonia lyase, was isolated.

The invention relates to a process for the preparation of L-amino acids, especially L-threonine, in which the following steps are carried out: a) fermentation of microorganisms of the family Enterobacteriaceae which produce the desired L-amino acid and in which the mglB gene, or nucleotide sequences coding therefor, is (are) enhanced and, in particular, overexpressed, b) enrichment of the desired L-amino acid in the medium or in the cells of the bacteria, and c) isolation of the desired L-amino acid.

,A potential biological control agent, Lygomusotima stria was collected in Thailand and Singapore and examined to determine if it was safe for release for Lygodium microphyllum. Old World climbing fern is one of the worst weeds of southern and central Florida. Old World climbing fern invades much of the southern peninsula of Florida where cost-effective, sustainable control methods are needed. Biological controls will assist land managers, reducing cost of control, and human exposure to pesticides. This agent has been recommended for field release by USDA APHIS.,Data in csv format included here is from a series of no-choice tests on neonate and third instars, oviposition, multigeneration, lower lethal temperature studies. Also included are native range collection information of L. stria and distribution data for the native Lygodium palmatum. A guide to the data files is included as 'Data files submitted to Ag Data Commons'.,

,Using the SHIME (an in vitro simulator of the human gut microbiome) we tracked the fate of the probiotic Lacticaseibacillus rhamnosus GG (LGG) over time and across colonic regions. Using fecal inoculum from three healthy human donors, reactors were established representing three colonic regions and both the luminal and mucosal microbiome in those regions. Community composition before, during, and after inoculation of the reactors with LGG as well as short chain fatty acid concentrations representing microbiome metabolic outputs. This dataset includes short-chain fatty acid concentrations and qPCR-based cell concentrations. Raw 16S rRNA amplicon sequencing of the V1-V2 regions can be found in the NCBI Sequence Read Archive associated with BioProject PRJNA893635: https://www.ncbi.nlm.nih.gov/bioproject/PRJNA893635.,Resources in this dataset:,

,This is an excel spreadsheet and equivalent comma delimited file containing absorbance data of Lactiplantibacillus pentosus, Lactococcus lactis, Enterobacteriaceae, and Leuconostocaceae growth in cucumber juice medium prepared from size 3A cucumbers. Such data was collected from continues measurements of absorbance from 96-well plates filled with cucumber juice medium expressed from size 3A cucumbers that was inoculated with the bacteria identified above. Absorbance was measured at 630 nm using a BioTek ELx808 Microstation or plate reader. The Excel spreadsheet with raw absorbance data was used for calculating growth rate in Table 3 of the associated publication.,