The present disclosure is directed to the properties of certain glycosyltransferase variants having N-terminal truncation deletions or internal deletions. Any of the mutants disclosed in here exhibit α-2,6-sialyltransferase enzymatic activity in the presence of CMP-activated sialic acid as co-substrate, and in the presence of a suitable acceptor site. A fundamental finding documented in the present disclosure is that such enzyme are not only capable of catalyzing transfer of a sialidyl moiety but they are also capable of catalyzing hydrolytic cleavage of terminally bound sialic acid from a glycan.

The properties of certain glycosyltransferase variants having N-terminal truncation deletions or internal deletions are disclosed. Particularly, mutants that exhibit α-2,6-sialyltransferase enzymatic activity in the presence of CMP-activated sialic acid as co-substrate, and in the presence of a suitable acceptor site, are disclosed. A fundamental finding documented in the present disclosure is that enzymes are not only capable of catalyzing transfer of a sialidyl moiety but they are also capable of catalyzing hydrolytic cleavage of terminally bound sialic acid from a glycan.

The properties of certain glycosyltransferase variants having N-terminal truncation deletions or internal deletions are disclosed. Particularly, mutants that exhibit α-2,6-sialyltransferase enzymatic activity in the presence of CMP-activated sialic acid as co-substrate, and in the presence of a suitable acceptor site, are disclosed. A fundamental finding documented in the present disclosure is that enzymes are not only capable of catalyzing transfer of a sialidyl moiety but they are also capable of catalyzing hydrolytic cleavage of terminally bound sialic acid from a glycan.

The subject invention provides improved methods for producing mannosylerythritol lipids (MEL) using yeasts not previously known to produce MEL. In particular, Meyerozyma guilliermondii (Pichia guilliermondii) is cultivated in a specially-tailored nutrient medium and under cultivation conditions such that the yeast unnaturally produces MEL and/or MEL-like molecules in greater amounts and at increased rates than when using standard MEL production with, for example, Pseudozyma aphidis. Yeast culture compositions are also provided, comprising yeast cells, growth medium, and high concentrations of MEL.

The subject invention provides improved methods for producing mannosylerythritol lipids (MEL) using yeasts not previously known to produce MEL. In particular, Meyerozyma guilliermondii (Pichia guilliermondii) is cultivated in a specially-tailored nutrient medium and under cultivation conditions such that the yeast unnaturally produces MEL and/or MEL-like molecules in greater amounts and at increased rates than when using standard MEL production with, for example, Pseudozyma aphidis. Yeast culture compositions are also provided, comprising yeast cells, growth medium, and high concentrations of MEL.

The present invention provides N-acetyl derivatives of sialic acids, including N-acetyl derivatives of Neu5Ac and Neu5Gc. Methods for preparing related precursors and a variety of sialosides are also disclosed.

The present invention provides N-acetyl derivatives of sialic acids, including N-acetyl derivatives of Neu5Ac and Neu5Gc. Methods for preparing related precursors and a variety of sialosides are also disclosed.

The present invention relates to a biotechnological method for producing a C-glycoside of interest. The invention further relates to the use of a sialylated C-glycoside as a donor in an enzymatic glycosylation reaction. The present invention further relates to the following C- glycosides.

The present invention relates to a process for preparing an alkyl polyglucoside by enzymatic catalysis, using sucrose or an analogue thereof as substrate and making it possible to obtain a large diversity of alkyl polyglucosides in terms of size and structure of the glucoside part thereof, making possible the obtaining of an alkyl polyglucoside with a number of glucosyl units that can be adjusted from 2 to 200 glucosyl units. The process also makes it possible to adjust the linear or branched structure of the carbohydrate part of the alkyl polyglucoside obtained, and also the nature of the glycosidic bonds linking the glucose residues within the carbohydrate part.

The present invention relates to a process for preparing an alkyl polyglucoside by enzymatic catalysis, using sucrose or an analogue thereof as substrate and making it possible to obtain a large diversity of alkyl polyglucosides in terms of size and structure of the glucoside part thereof, making possible the obtaining of an alkyl polyglucoside with a number of glucosyl units that can be adjusted from 2 to 200 glucosyl units. The process also makes it possible to adjust the linear or branched structure of the carbohydrate part of the alkyl polyglucoside obtained, and also the nature of the glycosidic bonds linking the glucose residues within the carbohydrate part.