Glucose feeds the TCA cycle via environmental ethanol in fermenting yeast

Ethanol and lactate are typical waste products of glucose fermentation. In mammals, glucose is catabolized by glycolysis into circulating lactate, which is broadly used throughout the body as a carbohydrate fuel. Individual cells can both uptake and excrete lactate, uncoupling glycolysis from glucose oxidation. Here we show that similar uncoupling occurs in the yeast Saccharomyces cerevisiae. Even in fermenting yeast that are net releasing ethanol, media 13C-ethanol rapid enters and is oxidized to acetaldehyde and acetyl-CoA. This is evident in exogenous ethanol being a major source of both cytosolic and mitochondrial acetyl units. 2H-tracing reveals that ethanol is also a major source of both NADH and NADPH, and this role is augmented under oxidative stress conditions. Thus, uncoupling of glycolysis from the oxidation of glucose-derived carbon via rapid reversible reactions is an ancient and conserved feature of eukaryotic metabolism.

The mitospecific domain of Mrp7 (bL27) supports mitochondrial translation during fermentation and is required for effective adaptation to respiration

We demonstrate here that mitoribosomal protein synthesis, responsible for the synthesis of oxidative phosphorylation (OXPHOS) subunits encoded by mitochondrial genome, occurs at high levels during glycolysis fermentation and in a manner uncoupled from OXPHOS complex assembly regulation. Furthermore, we provide evidence that the mitospecific domain of Mrp7 (bL27), a mitoribosomal component, is required to maintain mitochondrial protein synthesis during fermentation, but is not required under respiration growth conditions. Maintaining mitotranslation under high glucose fermentation conditions also involves Mam33 (p32/gC1qR homolog), a binding partner of Mrp7’s mitospecific domain, and together they confer a competitive advantage for a cell's ability to adapt to respiration-based metabolism when glucose becomes limiting. Furthermore, our findings support that the mitoribosome, and specifically the central protuberance (CP) region, may be differentially regulated and/or assembled, under the different metabolic conditions of fermentation and respiration. Based on our findings, we propose the purpose of mitotranslation is not limited to the assembly of OXPHOS complexes, but also plays a role in mitochondrial signaling critical for switching cellular metabolism from a glycolysis- to a respiratory-based state.

The effect of bioethanol mixture of raw coconut roomie (Cocos nucifera) with Pertamax (RON 92) and Pertalite (RON 90) fuels on the performance of a gasoline motor

Bioethanol is ethanol produced from glucose fermentation followed by the distillation process. The purpose of this study was to examine the performance of gasoline-fueled motors using bioethanol fuel mixed with pertamax (RON 90) and pertalite (RON92) fuels with a mixed percentage of B0%, B5%, B10%, B15%, and B20%. In this research, bioethanol is made from basic ingredients of coconut roomie (Cocos nucifera), which is fermented then continued with the distillation process to obtain bioethanol with a purity level of 80%. Bioetahnol is used as a fuel mixture using a gasoline fuel motor. The results of testing the mixture of bioethanol B20% and pertamax (RON 90) fuel with the highest torque is 11.94 Nm at rotation 2600 rpm. Bioethanol B20% and pertalite (RON 92) fuel with the highest torque is 11.79 Nm at rotation 2600 rpm. Bioethanol B20% and pertamax (RON 90) fuel the highest initial power is 4.58 hp at rotation 2900 rpm. Bioethanol B20% and pertalite (RON 92) fuel’s the highest power is 4.52 hp at rotation 2900 rpm. Bioethanol B20% and Pertamax (RON 90) fuel shows that the lowest specific fuel consumption is 0.28 kg/hp.h. Bioethanol B20% and pertalite (RON 92) fuel the lowest specific fuel consumption pertalite is 0.29 kg/hp.h. The greater the percentage of in pertamax (RON 90) fuel and pertalite (RON 92) fuel, the specific fuel consumption will be more efficient. In the mixture of pertamax (RON 90) fuel and bioethanol B20% is the largest value torque and power, but specific fuel consumption is the lowest.

Characterization and pathogenicity of symbiotic bacteria associated with entomopathogenic nematode: Steinernema species KALRO

The soil inhibiting entomopathogenic nematodes (EPNs), in the family Steinernematidae and Heterorhabditidae, are useful insect biological control agents. They have been used in the management of economically important crop pests. The EPNs are mutually associated with symbiotic bacteria genus Xenorhabdus and Photoharbdus respectively. The study aimed to isolate, characterize and evaluate the pathogenicity of symbiotic bacteria associated with EPN Steinernema sp. Kalro (Accession MW151701). The EPN Steinernema sp. Karlo was multiplied using the insect baiting technique. Its bacteria symbiont was isolated and characterized based on microscopic, biochemical, and physiological features like Gram staining, urease, motility test, and glucose fermentation test). Molecular identification and phylogenetic analysis were performed on 16S rDNA nucleotide sequence. Pathogenicity of the bacteria isolate was evaluated against Tuta absoluta larvae with mortality data recorded after 24 and 48hours of exposure to the bacterial cell suspension. The bacteria were found to be motile and glucose fermentation positive. Sequence analysis of 16S rDNA region resulted in 1500bp sequence with maximum similarity of between 97 and 98.93%, with Xenorhabdus spp Accessions from Genbank. It closely matched to Xenorhabdus sp. My8NJ with 98.93% similarity (Accession AB507811.1). Mean percent larval mortality of 68±4.9 and 88±8.0 in the lowest cell suspension was observed in 24 and 48h of exposure. It’s concluded that, the symbiotic bacteria associated with Steinernema sp. Kalro is Xenorhabdus sp. strain Kalro Genbank Accession MW245845. The bacteria is a potential biological control agent against Tuta absoluta larvae. Further classification of the bacteria to species level and pathogenicity trials in the screen house and field are recommended.

Blautia intestinalis sp. nov., isolated from human feces

A strictly anaerobic bacterial strain (27-44T) was isolated from a stool specimen from an autistic child collected in PR China. The strain was Gram-stain-positive, non-motile, non-pigmented, non-spore-forming, and cells were oval to rod-shaped. Strain 27-44T grew at 20–40 °C (optimal at 37 °C) and at pH 6.0–10 (optimal at 6.0–8.0). The major polar lipids were one phospholipid, two glycolipids, two aminophospholipids and one unidentified lipid. The major cellular fatty acids of strain 27-44T were C16 : 0 and C17 : 0 2-OH. The end product of glucose fermentation was mainly butyric acid. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain 27-44T was a member of the genus Blautia and phylogenetically closely related to Blautia obeum ATCC 29174T (with 97.8 % seque nce similarity). The genome of strain 27-44T was 3.5 Mbp with a DNA G+C content of 42.36 mol%. A total of 3436 genes were predicted and, of these, 3133 genes were annotated by KEGG. On the basis of phenotypic, chemotaxonomic and phylogenetic comparisons, strain 27-44T represents a novel species within the genus Blautia , for which the name Blautia intestinalis sp. nov. is proposed. The type strain is 27-44T= CGMCC 1.5285T=NBRC 113774T.

PROBIOTIC CANDIDATE PROTEOLYTIC Bacillus sp. COLLECTED FROM MANGROVE OF MARGASARI, LAMPUNG

Intensive shrimp culture has encountered many problems, such as declining water quality through disease caused by pathogenic microbes, which affected mortality. This study aimed to determine any potential probiotic from Bacillus sp. collected from mangrove in East Lampung, which could be used to improve the cultured shrimps' proteolytic and probiotic activity. This is a descriptive research with sampling and data collection of bacteria from many samples of mangrove. Result shows 128 isolates Bacillus from which then it has arrived at five potential probiotic Bacillus sp. The study five Bacillus sp. has been isolated with potential properties for probiotic (KPP212, IP121, UJ131, UJ132, SB141). Each isolate has characteristics with proteolytic property, growth in a wide range of pH 4–10 and osmotic stress (0–6% NaCl), non-pathogenic, ability for glucose fermentation, non-motile, and has negative catalase activity. The five potential Bacillus sp. can be used as probiotics for shrimp farming.

Strain-specific interaction of Fructilactobacillus sanfranciscensis with yeasts in the sourdough fermentation

Fructilactobacillus (F.) sanfranciscensis is a key bacterium in traditional (type 1) sourdough fermentations. It typically occurs in combination with the sourdough yeast Kazachstania (K.) humilis or the generalist Saccharomyces (S.) cerevisiae. Previous studies revealed intra-species diversity in competitiveness or dominance in sourdoughs of F. sanfranciscensis, as well as preferences for a life with or without a specific yeast. In this study representative, differently behaving strains were studied in media with different sugars and electron acceptors, and in rye sourdough fermentations in the presence and absence of K. humilis or S. cerevisiae. Strain-specific differences were observed in sugar and organic acids spectra in media, and in sourdoughs with F. sanfranciscensis strains in combination with K. humilis or S. cerevisiae. F. sanfranciscensis TMW 1.1150 proved dominant in the presence and absence of any yeast because it most effectively used maltose. Its maltose fermentation was unaffected by electron acceptors. F. sanfranciscensis TMW 1.2138 was the weakest maltose fermenter and incapable of glucose fermentation, and evidently not competitive against the other strains. F. sanfranciscensis TMW 1.392 was the most versatile strain regarding the utilization of different carbohydrates and its ability to exploit electron acceptors like fructose and oxygen. In sourdoughs without yeasts, it outcompeted other strains. The metabolism of F. sanfranciscensis TMW 1.907 was stimulated in combination with S. cerevisiae. In competitive trials, it was assertive only with S. cerevisiae. The intra-species differences in carbohydrate metabolism can widely explain the differences in their behavior in sourdough fermentation. Interaction between F. sanfranciscensis and the yeasts was strain specific and supposedly commensal with K. humilis and rather competitive with S. cerevisiae.

Comparative Proteomics Reveals the Anaerobic Lifestyle of Meat-Spoiling Pseudomonas Species

The ability of certain Pseudomonas (P.) species to grow or persist in anoxic habitats by either denitrification, acetate fermentation, or arginine fermentation has been described in several studies as a special property. Previously, we had isolated strains belonging to the species P. lundensis, P. weihenstephanensis, and P. fragi from anoxic modified atmosphere packaged (MAP) minced beef and further proved their anaerobic growth in vitro on agar plates. This follow-up study investigated the anaerobic growth of two strains per respective species in situ on inoculated chicken breast filet under 100% N2 modified atmosphere. We were able to prove anaerobic growth of all six strains on chicken breast filet with cell division rates of 0.2–0.8/day. Furthermore, we characterized the anaerobic metabolic lifestyle of these Pseudomonas strains by comparative proteomics, upon their cultivation in meat simulation media, which were constantly gassed with either air or 100% N2 atmospheres. From these proteomic predictions, and respective complementation by physiological experiments, we conclude that the Pseudomonas strains P. fragi, P. weihenstephanensis, P. lundensis exhibit a similar anaerobic lifestyle and employ arginine fermentation via the arginine deiminase (ADI) pathway to grow anaerobically also on MAP meats. Furthermore, glucose fermentation to ethanol via the ED-pathway is predicted to enable long term survival but no true growth, while respiratory growth with nitrate as alternative electron acceptor or glucose fermentation to acetate could be excluded due to absence of essential genes. The citric acid cycle is partially bypassed by the glyoxylate shunt, functioning as the gluconeogenetic route without production of NADH2 under carbon limiting conditions as e.g., in packaged meats. Triggered by an altered redox balance, we also detected upregulation of enzymes involved in protein folding as well as disulfide bonds isomerization under anoxic conditions as a counteracting mechanism to reduce protein misfolding. Hence, this study reveals the mechanisms enabling anaerobic grow and persistence of common meat-spoiling Pseudomonas species, and further complements the hitherto limited knowledge of the anaerobic lifestyle of Pseudomonas species in general.