Project description:Isolation and characterization of two recently isolated Novosphingobium oxfordensis sp. nov. and Novosphingobium mississippiensis sp. nov. strains from soil, with LCMS and genome-based investigation of their glycosphingolipid productions
Project description:Type II toxin-antitoxin (TA) systems are two-gene modules widely distributed among prokaryotes. GNAT toxins associated with the DUF1778 antitoxins represent a large family of type II TAs. GNAT toxins inhibit cell growth by disrupting translation via acetylation of aminoacyl-tRNAs. Using ribosome profiling, we investigated the in vivo substrate specificity of three GNAT toxins: AtaT2, TacT3, and ItaT.
Project description:Strain SM1988T is a Gram-negative, aerobic, oxidase- and catalase-positive, unipolar flagellated, and rod-shaped bacterium capable of hydrolyzing casein, gelatin and collagens. Phylogenetic analysis revealed that strain SM1988T formed a distinct phylogenetic lineage along with known genera within the family Pseudoalteromonadaceae, with 16S rRNA gene sequence similarity being less than 93.3% to all known species in the family. Based on the phylogenetic, genomic, chemotaxonomic and phenotypic data, strain SM1988T was considered to represent a novel species in a novel genus in the family Pseudoalteromonadaceae, for which the name Flocculibacter collagenilyticus gen. nov., sp. nov. is proposed, with the type strain being SM1988T (= MCCC 1K04279T = KCTC 72761T). Strain SM1988T showed a high production (236 U/mL) of extracellular collagenases, which had high activity against both bovine collagen and codfish collagen. Biochemical tests combined with genomic and secretomic analyses indicated that the collagenases secreted by strain SM1988T are serine proteases from the S8 family. These data suggest that strain SM1988T acts as an important player in marine collagen degradation and recycling and may have a promising potential in collagen resource utilization.
Project description:The Clostridioides difficile toxins TcdA and TcdB are responsible for diarrhea and colitis. The aim of this project was to explore the effects of the toxins on epithelial barrier function and the molecular mechanisms for diarrhea and inflammation. RNA-seq of toxin-treated intestinal cell monolayers was performed to describe the C. difficile-mediated effects. mRNA profiles from intestinale epithelial cells were generated by deep sequencing using Illumina NovaSeq 6000. This data provide the basis for subsequent upstream regulator analysis.
Project description:In humans there are two surfactant protein A (SP-A) functional genes SFTPA1 and SFTPA2 encoding innate immune molecules, SP-A1 and SP-A2, respectively, with numerous genetic variants each. SP-A interacts and regulates many of the functions of alveolar macrophages (AM). It is shown that SP-A variants differ in their ability to regulate the AM miRNome in response to oxidative stress (OxS). Because humans have both SP-A gene products, we were interested to determine the combined effect of co-expressed SP-A1/SP-A2 (co-ex) in response to ozone (O3) induced OxS on AM miRNome. Human transgenic (hTG) mice, carrying both SP-A1/SP-A2 (6A2/1A0, co-ex) and SP-A- KO were utilized. The hTG and KO mice were exposed to filtered air (FA) or O3 and miRNA levels were measured after AM isolation with or without normalization to KO. We found: (i) The AM miRNome of co-ex males and females in response to OxS to be largely downregulated after normalization to KO, but after Bonferroni multiple comparison analysis only in females the AM miRNome remained significantly different compared to control (FA); (ii) The targets of the significantly changed miRNAs were downregulated in females and upregulated in males; (iii) Several of the validated mRNA targets were involved in pro-inflammatory response, anti-apoptosis, cell cycle, cellular growth and proliferation; (iv) The AM of SP-A2 male, shown, previously to have major effect on the male AM miRNome in response to OxS, shared similarities with the co-ex, namely in pathways involved in the pro-inflammatory response and anti-apoptosis but also exhibited differences with the cell-cycle, growth, and proliferation pathway being involved in co-ex and ROS homeostasis in SP-A2 male. We speculate that the presence of both gene products versus single gene products differentially impact the AM responses in males and females in response to OxS.