Project description:L. plantarum is known to possess an L-lactate inducible lactate racemase activity (Goffin et al. 2005. J. Bacteriol. 187:6750). In the present study, microarrays were used in order to identify all genes that are up-regulated by L-lactate, but not by a racemic mixture of D- and L-lactate. A mutant of L. plantarum NCIMB8826 deficient for NAD-dependent L-lactate activity (TF101; Ferain et al. 1994. 176:596), and thus producing no L-lactate, was grown in MRS medium at 28°C until mid-exponential phase (OD600nm 0.75). The culture was then divided into 3 sub-cultures. Optically pure sodium L-lactate (200 mM) was added to the first sub-culture (TF101 + L-lac 200 mM). An equimolar mixture of sodium D- and L-lactate (100 mM each) was added to the second sub-culture (TF101 + L/D-lac 200 mM). The third sub-culture was not treated (TF101; reference sample). The three sub-cultures were further incubated at 28°C for 1h30 (a time known to be sufficient for induction of lactate racemase activity by L-lactate). Cells were harvested by centrifugation. Microarray data were used ot identify genes that are specifically induced by L-lactate (comparison of TF101 with TF101 + L-lac 200 mM), but not by DL-lactate (comparison of TF101 with T101 + L/D-lac 200 mM). There are no biological replicates.
Project description:Eubacterium limosum ATCC 8486 makes acetate and butyrate from various substrates and is found in the human intestine. The proteome of lactate-grown Eubacterium limosum was obtained in order to identify enzymes required for growth on this substrate, in particular to identify components that are unique to growth on lactate in comparison to other substrates for acetogenesis.
Project description:This study aimed to characterise the transcriptomic response of the lactate-utilizing bacteria, Coprococcus catus and Anaerobutyricum soehngenii, grown on varying carbon sources. This work has allowed for identification of divergent gene clusters in each species contributing to the lactate utilisation pathway.
Project description:Wound healing is associated with high rates of cell replication and lactate accumulation even under normoxic and hyperoxic conditions. Lactate accounts for various effects in tissue regeneration, such as collagen synthesis, angiogenesis, modulation of cytokine patterns and as recently shown for stem cell homing. Its influence on genes involved in cell replication has not been shown yet. Therefore, the effect of lactate considering genes involved in different cellular processes was investigated. Human umbilical vein endothelial cells (HUVEC) were cultured and incubated with lactate for different periods of time. Gene expression analysis was performed using custom-designed oligonucleotide microarrays. Keywords: Human gene expression study Reference design with Cy3 labeled uniRNA and Cy5 labeled sample RNA.
Project description:A metabolomics and whole cell lysate shotgun proteomics study was performed to investigate the glycolytic modes in Ca. Accumulibacter phosphatis.
Project description:Cultures were grown untill an optical density of 1.0. Cells were subsequently stressed with 2000 mM Na-lactate and samples were taken in time (15, 30, and 60 minutes). Samples were hybridized against a reference sample taken at t=0, just before addition of lactate. Biological duplicate was performed.
Project description:Experiment Description RNA sequencing was performed on Candida albicans wild type cells (SC5314) grown to exponential phase on YNB Lactate, YNB Glucose, or YNB Glucose plus Lactate, and compared to exponential Candida albicans crz1 cells grown on YNB Glucose or YNB Glucose plus Lactate. Three independent experiments were performed.
Project description:L. plantarum is known to possess an L-lactate inducible lactate racemase activity (Goffin et al. 2005. J. Bacteriol. 187:6750). In the present study, microarrays were used in order to identify all genes that are up-regulated by L-lactate, but not by a racemic mixture of D- and L-lactate.
Project description:Growth to mid exponential phase in M9 minimal media supplemented with 0.5% lactate versus growth in rich LB media Set of arrays organized by shared biological context, such as organism, tumors types, processes, etc. Media: M9 minimal media with 0.5% lactate Computed
Project description:The organic acids lactate and diacetate are commonly used in combination in ready-to-eat foods because they show synergistic, i.e. greater than additive, ability to inhibit the growth of Listeria monocytogenes. Full genome microarrays were used to investigate the synergistic transcriptomic response of two L. monocytogenes strains, h7858 (serotype 4b) and f6854 (serotype 1/2a), to organic acid, under conditions controlling for osmotic and cold stress. Strains were exposed to BHI broth at 7°C with 4.65% water phase (w.p.) NaCl at pH 6.1 treated with 2% w.p. potassium lactate, 0.14% w.p. sodium diacetate, the combination of both at the same levels, or no inhibitors as control. RNA was extracted 8h after exposure, during lag phase, to capture gene expression changes during adaptation to the organic acid stress. Treatment with organic acids induced massive global transcriptional changes, with 1041 and 640 genes differentially expressed in h7858 and f6854. Major effects of treatment with lactate and diacetate are (i) a total of 474 and 209 genes, for h7858 and f6854, that showed synergistic expression differences, (ii) differential expression of membrane ion transport genes including those encoding ABC transporters of metals and decreased multi-drug transporter expression many ABC, PTS, and drug transporter systems, including increased PTS sugar transport and decreased multi-drug transporter expression, and (iii) altered metabolism including induction of a nutrient limiting stress response, reduction of menaquinone biosynthesis, and a shift from fermentative production of lactate and acetate and lactate to energetically less favorable, neutral acetoin. These data suggest that additional synergies in L. monocytogenes growth inhibition could be achieved by treatments that interfere with cellular energy generation processes. The dye-swapped, single loop design hybridizes a single biological replicate of both 2% water phase lactate (PL) and 0.14% water phase acetate (SDA) treatments to both the control (CTRL) and combination (PLSDA) treatments (4 hybridizations), using opposite dye labels for each sample, and a second biological replicate is hybridized with dye assignments swapped (4 more hybridizations) to balance labeling effects. The design was repeated twice comprising 16 hybridizations over 4 biological replicates for each strain, and 32 total hybridizations over both h7858 and f6854.