Provided is a galactose mutarotase gene promoter derived from Lactobacillus casei and the use thereof, and more particularly, to a Lactobacillus casei-derived galactose mutarotase gene promoter having the nucleotide sequence of SEQ ID NO: 1, an expression vector containing the promoter, and a microorganism transformed with the expression vector. A microorganism transformed with an expression vector containing the promoter may effectively express a target protein on the cell surface, and thus is useful as a vaccine vehicle or the like. Moreover, provided is a surface expression vector having pgsA, which is a gene encoding poly-gamma-glutamate synthetase, and a method of expressing a target protein on the microbial surface using the vector. The vector containing foreign genes inserted therein is transformed into a microorganism and allows a foreign protein is to be stably expressed on the surface of the microorganism.

Provided is a vector capable of co-expressing two different target proteins on the microbial surface using two promoters derived from Lactobacillus, and a method of expressing target proteins on the microbial surface using the vector. The vector containing foreign genes inserted therein is transformed into a microorganism, and allows different foreign proteins to be stably expressed on the surface of the microorganism. Furthermore, provided is a surface expression vector containing the gene pgsA encoding a poly-gamma-glutamate synthetase complex, and a method of expressing a target protein on the microbial surface using the vector. The vector containing foreign genes inserted therein is transformed into a microorganism, and allows the foreign proteins to be stably expressed on the surface of the microorganism.

The present disclosure is based upon the identification of a number of Streptococcus agalactiae genes which are required for virulence in fish species. Specifically, the disclosure relates to genomic content present in fish-associated S. agalactiae strains that is absent from strains which are non-virulent to fish. Further disclosed is the use of a number of S. agalactiae proteins and antigens in methods, immunogenic compositions and vaccines for raising immune responses and treating or preventing diseases, conditions and/or infections with a Streptococcal aetiology.

The invention relates to a method for obtaining a mutant Yarrowia yeast strain capable of growing on D-galactose as sole carbon source, comprising over expressing in said strain a galactokinase, a galactose-1-phosphate uridyl transferase, an UDP-glucose-4 epimerase and a galactose mutarotase. The invention also relates to a mutant Yarrowia strain obtained by said method.

Provided is a galactose mutarotase gene promoter derived from Lactobacillus casei and the use thereof, and more particularly, to a Lactobacillus casei-derived galactose mutarotase gene promoter having the nucleotide sequence of SEQ ID NO: 1, an expression vector containing the promoter, and a microorganism transformed with the expression vector. A microorganism transformed with an expression vector containing the promoter may effectively express a target protein on the cell surface, and thus is useful as a vaccine vehicle or the like. Moreover, provided is a surface expression vector having pgsA, which is a gene encoding poly-gamma-glutamate synthetase, and a method of expressing a target protein on the microbial surface using the vector. The vector containing foreign genes inserted therein is transformed into a microorganism and allows a foreign protein is to be stably expressed on the surface of the microorganism.