microbeMASST: A Taxonomically-informed Mass Spectrometry Search Tool for Microbial Metabolomics Data

microbeMASST, a taxonomically informed mass spectrometry (MS) search tool, tackles limited microbial metabolite annotation in untargeted metabolomics experiments. Leveraging a curated database of >60,000 microbial monocultures, users can search known and unknown MS/MS spectra and link them to their respective microbial producers via MS/MS fragmentation patterns. Identification of microbe-derived metabolites and relative producers without a priori knowledge will vastly enhance the understanding of microorganisms’ role in ecology and human health

Influence of Fenofibrate treatment on triacylglycerides diacylglycerides and fatty acids in fructose fed rats

Fenofibrate (FF) lowers plasma triglycerides via PPARα activation. Here, we analyzed lipidomic changes upon FF treatment of fructose fed rats. Three groups with 6 animals each were defined as control, fructose-fed and fructose-fed/FF treated. Male Wistar Unilever Rats were subjected to 10% fructose-feeding for 20 days. On day 14, fenofibrate treatment (100 mg/kg p.o.) was initiated and maintained for 7 days. Lipid species in serum were analyzed using mass spectrometry (ESI-MS/MS; LC-FT-MS, GC-MS) on days 0, 14 and 20 in all three groups. In addition, lipid levels in liver and intestine were determined. Short-chain TAGs increased in serum and liver upon fructose-feeding, while almost all TAG-species decreased under FF treatment. Long-chain unsaturated DAG-levels (36:1, 36:2, 36:4, 38:3, 38:4, 38:5) increased upon FF treatment in rat liver and decreased in rat serum. FAs, especially short-chain FAs (12:0, 14:0, 16:0) increased during fructose-challenge. VLDL secretion increased upon fructose-feeding and together with FA-levels decreased to control levels during FF treatment. Fructose challenge of de novo fatty acid synthesis through fatty acid synthase (FAS) may enhance the release of FAs ≤16:0 chain length, a process reversed by FF-mediated PPARα-activation

Transcriptional and Proteomic Profiles of Group B Streptococcus Type V Reveal Potential Adherence Proteins Associated with High-Level Invasion

Group B Streptococcus (GBS) is an opportunistic organism that can harmlessly colonize the human gut, vagina, and rectum but can also cause pneumonia, sepsis, and meningitis in neonates born to colonized mothers. We have shown previously that growth rate and oxygen level regulate the ability of GBS to invade eukaryotic cells in vitro. Herein we extend and expand on these observations to show that GBS type V, an emergent serotype, grown in a chemostat at a cell mass-doubling time (t(d)) of 1.8 h with oxygen invaded human ME-180 cervical epithelial cells in large numbers compared with those grown at the same t(d) without oxygen or at a slower t(d) of 11.0 h. The fact that several GBS type V cell wall-associated and membrane proteins were expressed exclusively under the invasive growth condition prompted an investigation, using genomics and proteomics, of all upregulated genes and proteins. Several proteins with potential roles in adherence were identified, including an undefined surface antigen (SAG1350), a lipoprotein (SAG0971), penicillin-binding protein 2b (SAG0765), glyceraldehyde-3-phosphate dehydrogenase (SAG0823), and an iron-binding protein (SAG1007). Mouse antisera to these five proteins inhibited binding of GBS type V to ME-180 cells by ≥85%. Recombinant undefined surface antigen (SAG1350), lipoprotein (SAG0971), and penicillin-binding protein 2b (SAG0765) each bound to ME-180 cells in a dose-dependent fashion, confirming their ability to act as ligands. Collectively, these data increase the number of potential GBS adherence factors and also suggest a role for these surface-associated proteins in initial pathogenic events

NEFA-species in rat liver and rat serum.

<p><b>A</b> NEFA-species in rat liver homocysteine in rat serum; <b>B</b> NEFA-species in rat serum. The control group is shown as black bar, the fructose-fed group is shown as red bar and the FF treated group is shown as a blue bar; values given are means±s.d.; significant changes are indicated using *: P<0.05; **: P<0.01; ***: P<0,001.</p

Alternate display format of TAG/DAG-species and FA-species.

<p><b>A</b> fructose-feeding vs control in rat liver; <b>B</b> FF treatment vs Fructose-feeding in rat liver; <b>C</b> fructose-feeding vs control in rat serum; <b>D</b> FF treatment vs Fructose-feeding in rat serum; An algorithm was developed to generate the alternate display form of DAG/TAG-species. In the diagrams the species shown in red have increased levels between the two respective groups, while a blue color indicates a decreased level of the respective species between the two groups. A black coloring indicates no change of the species between the two groups. All species have been colored if the difference of levels between the two groups were >5% of the total amount of the higher level, regardless of the significance of the change. For clarity, only the sections of the diagram containing the combinations of DAG C36 With FA C18 to yield TAG C54 are shown. If there is a fatty acid-DAG combination present with the same direction of change as the corresponding TAG-species, then this combination seems at least to contribute to the composition of the TAG-species. Significant changes are indicated using *: P<0.05; **: P<0.01; ***: P<0,001.</p

DAG-species in rat liver and serum.

<p>DAG-species in <b>A</b> rat liver and <b>B</b> rat serum. Values given are means±s.d. of the sums of the different chain lengths (C32 – C38) on the left and degree of desaturation (sat – hexa) on the right. Serum data is shown for day 14 and day 20; the control group is shown as black bar, the fructose-fed group is shown as red bar and the FF treated group is shown as a blue bar; significant changes are indicated using *: P<0.05; **: P<0.01; ***: P<0,001.</p

TAG-species in rat liver.

<p>Values given are means±s.d. of the sums of the different chain lengths (C46–C60) on the left and degree of desaturation (sat – deca) on the right. Serum data is shown for day 14 and day 20; the control group is shown as black bar, the fructose-fed group is shown as red bar and the FF treated group is shown as a blue bar; significant changes are indicated using *: P<0.05; **: P<0.01; ***: P<0,001.</p

VLDL-secretion after FF treatment.

<p>The control group is shown in black, the fructose-fed group is shown in red and the FF treated group is shown in blue; values given are means±s.d.; significant changes are indicated using *: P<0.05; **: P<0.01; ***: P<0,001.</p

Clinical chemistry data, organ weight, food and water consumption.

<p>Values determined in study 1. Values given are mean values of the 6 animals/group with standard deviation included. Significant changes are indicated using *: P<0.05; **: P<0.01; ***: P<0,001. ASAT: aspartate aminotransferase, ALAT: alanine aminotransferase, AP: alkaline phosphatase (AP).</p><p>Clinical chemistry data, organ weight, food and water consumption.</p