Provided herein are host cells capable of producing hybrid oligosaccharides and polysaccharides, wherein said hybrid oligosaccharides and polysaccharides do not comprise a hexose at the reducing end of their first repeat unit. Also provided herein are hybrid oligosaccharides or polysaccharides and bioconjugates which can be produced by the host cells described herein, wherein said bioconjugates comprise a carrier protein linked to a hybrid oligosaccharide or polysaccharide that does not comprise a hexose at the reducing end of its first repeat unit.

The invention provides a method and composition for the treatment, prevention, and diagnosis of cancer containing or derived from cancer stem cells.

Provided herein are host cells capable of producing hybrid oligosaccharides and polysaccharides, wherein said hybrid oligosaccharides and polysaccharides do not comprise a hexose at the reducing end of their first repeat unit. Also provided herein are hybrid oligosaccharides or polysaccharides and bioconjugates which can be produced by the host cells described herein, wherein said bioconjugates comprise a carrier protein linked to a hybrid oligosaccharide or polysaccharide that does not comprise a hexose at the reducing end of its first repeat unit.

The present disclosure relates to compositions and methods useful for the production of recombinant glycoproteins in filamentous fungal cells, such as Trichoderma cells, wherein at least 90% (mol %), preferably at least 95% of the total neutral N-glycans of said produced recombinant glycoprotein are mammalian-like N-glycans. More specifically, the invention provides a filamentous fungal cell comprising i. one or more mutations that reduces or eliminates one or more endogenous protease activity compared to a parental filamentous fungal cell which does not have said mutation(s); ii.a polynucleotide encoding a heterologous catalytic subunit of oligosaccharyl transferase; iii. a recombinant polynucleotide for increasing 1, 2 mannosidase activity;and, iv. a recombinant polynucleotide encoding said heterologous glycoprotein.

Methods of producing bioconjugates of O-antigen polysaccharides covalently linked to a carrier protein using recombinant host cells are provided. The recombinant host cells used in the methods described herein encode a particular oligosaccharyl transferase enzyme depending on the O-antigen polysaccharide bioconjugate to be produced. The oligosaccharyl transferase enzymes can be PglB oligosaccharyl transferase or variants thereof. Also provided are compositions containing the bioconjugates, and methods of using the bioconjugates and compositions described herein to vaccinate a subject against extra-intestinal pathogenic E. coli. (ExPEC).

Ascomycetous filamentous fungi genetically modified to produce proteins having reduced or no N-glycans of mammalian proteins are provided, comprising deletion or disruption of stt3 and/or cwh8 genes.