4 results about "Phosphomannose Isomerase" patented technology

The invention belongs to the technical field of gene engineering, and particularly relates to a method for preparing low-O-glycosylation recombinant XVII type triple helix collagen. The method comprises the following steps: obtaining recombinant plasmids for expressing recombinant XVII type humanized collagen, obtaining a strain for overexpressing phosphomannose isomerase (PMI), then carrying out linear treatment on the recombinant plasmids, transferring the recombinant plasmids into the strain, carrying out fermentation culture, and precipitating the recombinant XVII type humanized collagen after fermentation is finished, so as to obtain the recombinant XVII type humanized collagen. The recombinant protein is the low O-glycosylation recombinant X VII type humanized collagen. According to the method, in the preparation process, the metabolic rate of 6-phosphomannose in cells is increased, accumulation of a large amount of 6-phosphomannose in the cells is restrained, so that O-glycosylation modification of the X VII type humanized collagen is reduced, the influence of unnecessary glycosylation modification on a protein space structure and biological functions is avoided, and by means of the method, the yield of the X VII type humanized collagen is increased. The expression level of the recombinant XVII type humanized collagen can be obviously improved, and the protein yield is improved.

The invention belongs to the technical field of gene engineering, and particularly relates to a preparation method of low-O-glycosylation recombinant III-type humanized collagen. The method comprises the following steps: obtaining recombinant plasmids for expressing recombinant III-type humanized collagen, obtaining a strain for overexpressing phosphomannose isomerase (PMI), then carrying out linear treatment on the recombinant plasmids, transferring the recombinant plasmids into the strain, carrying out fermentation culture, and precipitating the recombinant III-type humanized collagen after the fermentation is ended, so as to obtain the recombinant III-type humanized collagen. The recombinant III type humanized collagen with low O-glycosylation is obtained. According to the method, in the preparation process, the metabolic rate of 6-phosphomannose in cells is increased, accumulation of a large amount of 6-phosphomannose in the cells is restrained, O-glycosylation modification of III-type humanized collagen is reduced, the influence of unnecessary glycosylation modification on the protein space structure and biological functions is avoided, and through the method, the yield of the collagen is increased. The expression level of the recombinant III-type humanized collagen can be obviously improved, and the protein yield is improved.

The invention discloses a platycodon grandiflorum phosphomannose isomerase gene PgPMI as well as an encoded product and application thereof, and belongs to the technical field of platycodon grandiflorum genes. According to the invention, the platycodon grandiflorum phosphomannose isomerase gene PgPMI is cloned from platycodon grandiflorum, and the nucleotide sequence of the platycodon grandiflorum phosphomannose isomerase gene PgPMI is shown as SEQ ID NO. 1. According to the invention, the expression of the PgPMI gene in escherichia coli is successfully realized, and an enzymatic experiment verifies that the PgPMI has catalytic activity, so that mannose-6-phosphoric acid and fructose-6-phosphoric acid can be mutually converted, and a foundation is laid for revealing biosynthesis of platycodon grandiflorum polysaccharide. In addition, the platycodon grandiflorum phosphomannose isomerase can also be applied to biosynthesis pathways of plant ascorbic acid, cell walls, glycosylated proteins, lipoproteins, glycosyl phosphate inositol ankyrin and the like.

The invention provides an application of a phosphomannose isomerase (MPI) inhibitor in tumor treatment. In particular, the present invention provides uses of MPI inhibitors, such as ebbeselenium, in the treatment or prevention of tumors. The MPI inhibitor, such as ebbeselenium, can combine and inhibit the enzyme activity of phosphomannose isomerase, block protein N-glycosylation and further inhibit the proliferation of tumor cells such as envelop hepatocellular carcinoma.