A microbial composition for improving the conditions in animal farms comprising: a slow-releasing carrier base having a first predetermined percentage by weight (w/w %); and a mixture of microorganisms identified in a 16S rRNA gene sequence so that the composition is capable of denitrification, feces decomposition, and hydrogen sulfide (H.sub.2S) oxidation.

Compositions and methods are provided comprising acetolactate decarboxylase (ALDC) enzyme variants having higher specific activity. Composition and method are provided where the ALDC variants are used in combination with metal ions to further increase stability and/or activity.

The disclosure discloses recombinant Bacillus subtilis for synthesizing guanosine diphosphate fucose and a construction method and application thereof. The recombinant Bacillus subtilis is obtained by intensively expressing guanylate kinase and nucleotide diphosphokinase genes and expressing exogenous fucokinase and phosphate guanylyltransferase genes in a genome of Bacillus subtilis 168. According to the disclosure, a bacterial strain for synthesizing the guanosine diphosphate fucose is obtained by reconstructing the Bacillus subtilis 168, with a volume of intracellular accumulation up to 196.15 g/L. According to the disclosure, by intensively expressing the guanylate kinase and nucleotide diphosphokinase genes, and enhancing the supply of intracellular GDP-L-fucose composition cofactors, the synthesis of the guanosine diphosphate fucose is promoted. The construction method for the recombinant Bacillus subtilis of the disclosure is simple and convenient to use, thus having good application prospects.

Phenotypically modified bioengineered microbial spores are provided. The microbial spores may be used in various spore-based technologies such as probiotics, biomaterials and vaccines.

The present invention is related to sustainable fermentation processes with increased efficiency and less environmental impact. Particularly, the present invention is related to a process wherein in one fermentation process two or more fermentation products can be produced and isolated, i.e. a “primary” fermentation product and a “secondary” fermentation product, particularly wherein one is a water soluble organic compound and one is a fat-soluble organic compound particularly a fat-soluble vitamin, preferably vitamin K2.

The invention is directed to novel probiotic bacterial strains that colonize animal tissues, and in particular the gastrointestinal (GI) tract of aquatic animals grown in aquaculture environments and may further be engineered to express and deliver interfering RNA molecules configured to downregulate expression of one or more pathogen, or endogenous host genes.

The present invention provides a pyruvate-responsive biosensor and a construction method and use thereof. In the present invention, pyruvate-responsive biosensors with different dynamic ranges are successfully constructed by optimizing the PdhR binding sequence inserted on the P43 promoter and optimizing the insertion site, wherein the minimum increase in dynamic range is by 0.6 time, and the maximum increase is by 30.7 times. The pyruvate-responsive biosensors are useful in the precise control of the expression of each gene in the cell. Since pyruvate is a key metabolite of central carbon in the cells, these biosensors are capable of dynamically regulating the expression level of intracellular genes according to changes in the content of pyruvate in the cells, thereby achieving the dynamic control of intracellular metabolic flux. The pyruvate biosensor obtained in the present invention has a good specificity, and a response range to pyruvate of 10-35 nmol/g DCW.

The disclosure discloses a method for efficient biosynthesis of Reb D by glycosyltransferase, belonging to the field of biocatalytic synthesis. According to the disclosure, a glycosyltransferase having an activity to catalyze synthesis of Reb D from Reb A is obtained, and a mutant YojK-I241T/G327N with high catalytic activity is obtained through directed evolution. The glycosyltransferase mutant YojK-I241T/G327N and a sucrose synthase AtSuSy derived from Arabidopsis thaliana are used for constructing a coupling reaction to realize efficient catalytic synthesis of Reb D with Reb A as a substrate. The reaction is carried out by using 19.32 g/L (20 mmol/L) of Reb A as the substrate for 15 h to efficiently synthesize 20.59 g/L of Reb D, and the yield of Reb D reaches 91.29%, which provides an efficient and green new pathway for production of Reb D.

A biological indicator for determining the efficacy of an oxidative sterilization process, and its methods of use. The biological indicator comprises a set of microbial spores, at least one fluorescent sensor protein, and a culture medium, the fluorescent sensor protein being capable of yielding an optically detectable signal when the fluorescent sensor protein is not in a denatured state due to the oxidative sterilization process, and a different optically detectable signal when the fluorescent sensor protein is in a denatured state after the oxidative sterilization process.

The present disclosure provides a novel serine protease variant.