The present disclosure relates to the field of genetic engineering, especially relates to a xylose-induced genetically engineered bacteria used for producing ectoine as well as a construction method and use thereof The genetically engineered bacteria is constructed by heterologously expressing the ectABC gene cluster from Halomonas elongata on the E. coli chromosome, using the promoter of xylose transporter coding gene xylF to control the RNA polymerase from T7 bacteriophage, reconstructing a synthesis pathway of ectoine and constructing a plasmid-free system, and enhancing the expression of target genes by a strong promoter T7; the yiled of ectoine reached 12-16 g/L after 20-28 h fermentation in shake flask, and reached 35-50 g/L after 24-40 h fermentation in a 5 L fermentor.

The present invention relates to the field of bio-production of ectoine. There is a need in the art for ectoine production methods allowing its highly efficient synthesis and secretion. The solution proposed in the present invention is the use of a genetically modified yeast comprising many modifications as described in the present text.

The present invention relates to a microorganism genetically modified for production of ectoine, wherein said microorganism comprises the following modifications: expression of a heterologous gene ectA encoding a diaminobutyric acid acetyltransferase having at least 90% similarity with SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, SEQ ID NO: 4 or SEQ ID NO: 5, a heterologous gene ectB encoding a diaminobutyric acid aminotransferase having at least 90% similarity with SEQ ID NO: 6, SEQ ID NO: 7, SEQ ID NO: 8, SEQ ID NO: 9 or SEQ ID NO: 10, a heterologous gene ectC encoding an ectoine synthase having at least 90% similarity with SEQ ID NO: 11, SEQ ID NO: 12, SEQ ID NO: 13, SEQ ID NO: 14 or SEQ ID NO: 15 and deletion of pykA and pykF genes. The present invention also relates to a method for the production of ectoine using said microorganism.

The present disclosure relates to the field of genetic engineering, especially relates to a xylose-induced genetically engineered bacteria used for producing ectoine as well as a construction method and use thereof. The genetically engineered bacteria is constructed by heterologously expressing the ectABC gene cluster from Halomonas elongata on the E. coli chromosome, using the promoter of xylose transporter coding gene xylF to control the RNA polymerase from T7 bacteriophage, reconstructing a synthesis pathway of ectoine and constructing a plasmid-free system, and enhancing the expression of target genes by a strong promoter T7; the yield of ectoine reached 12-16 g/L after 20-28 h fermentation in shake flask, and reached 35-50 g/L after 24-40 h fermentation in a 5 L fermentor.

The present invention relates to the field of bio-production of ectoine. There is a need in the art for ectoine production methods allowing its highly efficient synthesis and secretion. The solution proposed in the present invention is the use of a genetically modified yeast comprising many modifications as described in the present text.