Provided herein are methods for integrating a gene of interest into a chromosome of a host cell. In some embodiments, the methods include introducing into a host cell a first plasmid comprising a transposase coding sequence and a donor sequence, which includes a selectable marker coding sequence flanked by a first and a second lox site and is itself flanked by inverted repeats recognized by the transposase. Following transposase-mediated chromosomal integration of the donor sequence into the host cell, a second plasmid is introduced, which comprises the gene of interest and a second selectable marker coding sequence, both flanked by a first and a second lox site. The gene of interest is chromosomally integrated into the host cell by recombinase-mediated cassette exchange (RMCE) between the donor sequence and the second plasmid via Cre-/cuc recombination. Further provided herein are host cells, vectors, and methods of producing a product related thereto.

The present invention belongs to microbial technology field and relates to a strain producing toluene o-xylene monooxygenase (Arthrobacter woluwensis) HW-1 and its application in preparation of 5-methylpyrazine-2-carboxylic acid by microbial fermentation. The present invention providing a new strain HW-1 which could produce toluene o-xylene monooxygenase, and the strain is identified as Arthrobacter woluwensis. The strain is firstly found to convert 2, 5-dimethylpyrazine by bio-fermentation to obtain the medicine intermediate 5-methylpyrazine-2-carboxylic acid. The concentration of accumulated product could reach 34.19 g/L and the yield rate is 81.4% by shake flask fermentation. Compared with 20.41 g/L reported in the literature, this method has a greater advantage and could be industrialized. The conditions to prepare 5-methylpyrazine-2-carboxylic acid provided in the present invention is mild, the reaction process is controllable and has good performance in environmental protection and energy saving. So this invention has great value in industry.

The present invention belongs to microbial technology field and relates to a strain producing toluene o-xylene monooxygenase (Arthrobacter woluwensis) HW-1 and its application in preparation of 5-methylpyrazine-2-carboxylic acid by microbial fermentation. The present invention providing a new strain HW-1 which could produce toluene o-xylene monooxygenase, and the strain is identified as Arthrobacter woluwensis. The strain is firstly found to convert 2, 5-dimethylpyrazine by bio-fermentation to obtain the medicine intermediate 5-methylpyrazine-2-carboxylic acid. The concentration of accumulated product could reach 34.19 g/L and the yield rate is 81.4% by shake flask fermentation. Compared with 20.41 g/L reported in the literature, this method has a greater advantage and could be industrialized. The conditions to prepare 5-methylpyrazine-2-carboxylic acid provided in the present invention is mild, the reaction process is controllable and has good performance in environmental protection and energy saving. So this invention has great value in industry.

The present invention relates to a bio-assisted method for treatment of spent caustic by treating with haloalkaliphilic consortium of bacteria capable of reducing or transforming sulphides, thiols, mercaptants and other sulphur containing compounds, phenols, hydrocarbons, naphthenic acids and their derivatives in spent caustic.

An -salidroside, a method for preparing same, and application thereof. A novel type of salidroside, namely, -salidroside, which when compared with the known -salidroside, -salidroside exhibits superior activity in scavenging DPPH radicals and hydroxyl radicals and can be added as a new functional ingredient to cosmetics or anti-fatigue health supplements. The method for preparing -salidroside involves using inexpensive starch, etc., as a glycosyl donor and tyrosol as a substrate, synthesizing -salidroside under the action of glycosyltransferase. The glycosyltransferase has strict specificity and chiral catalytic ability, enabling the specific generation of -salidroside.

An Arthrobacter gandavensis strain having an activity against Clostridium perfringens selected from the strains AP1 filed with DSMZ on Feb. 19, 2014 under the number DSM 28444, AP2 filed with DSMZ on Feb. 19, 2014 under the number DSM 28445, AP3 filed with DSMZ on Feb. 19, 2014 under the number DSM 28446 or AP4 filed with DSMZ on Feb. 19, 2014 under the number DSM 28447.

The present invention has objects to provide a glucan useful as water-soluble dietary fiber, its preparation and uses. The present invention solves the above objects by providing a branched -glucan, which is constructed by glucose molecules and characterized by methylation analysis as follows: (1) Ratio of 2,3,6-trimethyl-1,4,5-triacetyl-glucitol to 2,3,4-trimethyl-1,5,6-triacetyl-glucitol is in the range of 1:0.6 to 1:4; (2) Total content of 2,3,6-trimethyl-1,4,5-triacetyl-glucitol and 2,3,4-trimethyl-1,5,6-triacetyl-glucitol is 60% or higher in the partially methylated glucitol acetates; (3) Content of 2,4,6-trimethyl-1,3,5-triacetyl-glucitol is 0.5% or higher but less than 10% in the partially methylated glucitol acetates; and (4) Content of 2,4-dimethyl-1,3,5,6-tetraacetyl-glucitol is 0.5% or higher in the partially methylated glucitol acetates; a novel -glucosyltransferase which forms the branched -glucan, processes for producing them, and their uses.