The present invention is directed to isolated microorganisms as well as strains and mutants thereof, biomasses, microbial oils, compositions, and cultures; methods of producing the microbial oils, biomasses, and mutants; and methods of using the isolated microorganisms, biomasses, and microbial oils.

An object of the present invention is to provide a microorganism that efficiently produces EPA and a method for producing EPA using the microorganism. The present invention relates to a microorganism having an ability to produce docosahexaenoic acid (DHA), wherein the microorganism contains a protein composed of an amino acid sequence in which at least one of the amino acid residues at positions 6, 65, 230, 231, and 275 in the amino acid sequence represented by SEQ ID NO: 2 has been substituted with another amino acid residue (mutated OrfB), and is capable of producing eicosapentaenoic acid (EPA), and the like.

The invention provides a recombinant Thraustochytriaceae cell for the production of a glycomolecule. The cell comprises a nucleic acid encoding a heterologous glycomolecule, and a sequence encoding a heterologous oligosaccharyltransferase. The cell produces the heterologous glycomolecule having a higher glycan occupancy compared to the same heterologous glycomolecule produced by a corresponding cell not comprising the heterologous oligosaccharyltransferase. The glycan occupancy can be more than 25%. The cells advantageously produce and, optionally secrete, the heterologous glycomolecule. Thus, the invention provides recombinant organisms that provide glycomolecules having a glycosylation profile that is more similar to the glycosylation profile produced in a manunalian cell.

The present invention describes methods of identifying high-risk populations or individuals who have positive serology for T. gondii. These methods include obtaining a biological sample from a subject; determining the level of T. gondii cyst antigen antibody in the biological sample; and characterizing the biological sample in at least one of three categories.

A strain of ciliated protozoan is provided, which has an obvious promoting effect on germination and growth of plant seeds. The ciliated protozoan is Colpoda sp. JH2-5-4, with preservation number of CCTCC NO.C202229. After collecting over 2,000 Colpoda strains from soils across China, the present invention has screened and selected a highly efficient and active strain suitable for use as a microbial fertilizer in plant cultivation. The selected ciliated protozoan can significantly shorten the germination time of plant seeds and improve seedling survival rate.

Improved labyrinthulomycetes strains that produce microbial oils having increased docosahexaenoic acid (DHA) content are disclosed. The strains have increased productivity with respect to a wild type strain. Also provided are microbial oil compositions having increased DHA content. Methods of improving strains for the production of lipid, such as DHA, are also included.

The present invention relates to recombinant cells and microorganisms of the phylum Labyrinthulomycota and their use in heterologous protein production. Novel promoter, terminator, and signal sequences for efficient production and, optionally, secretion of polypeptides from recombinant host cells and microorganisms are also encompassed by the present invention.

The present invention is directed to isolated microorganisms as well as strains and mutants thereof, biomasses, microbial oils, compositions, and cultures; methods of producing the microbial oils, biomasses, and mutants; and methods of using the isolated microorganisms, biomasses, and microbial oils.

Described herein are compositions and methods of producing glycosylated proteins in vitro and in vivo. The methods include using host cells to produce glycosylated proteins. Also described herein are glycosylated proteins produced using such methods and uses thereof.

The present invention relates to an oil of microorganisms rich in docosahexaenoic acid (DHA, C22:6n3), comprising more than 60% of DHA relative to the total mass of fat and to the use thereof for human or animal feed, in particular for feeding infants, children, or pregnant or lactating women.