Abstract: The invention relates to a DNA fragment of SEQ ID NO: 1 herein and encoding the SEQ ID NO: 2 peptide sequence herein. This DNA sequence carries the gene encoding the enzyme for fragmenting N-acetylheparosan and the adjacent sequences permitting its expression. The invention also relates to an enzyme intended for fragmenting N-acetylheparosan derived from this gene and the processes for fragmenting high molecular mass N-acetylheparosan using this enzyme.

Abstract: The subject of the invention is new high molecular mass N,O-sulphated heparosans consisting of chains or of a mixture of chains having a molecular mass of between 1.5.times.10.sup.4 and 4.0.times.10.sup.6 D, characterized by a repeating disaccharide structure of formula I: ##STR1## in which E represents, in 0 to 80% of the disaccharide units of the said N,O-sulphated heparosan, an acetyl group and, in the remaining disaccharide units, a sulphate group and optionally a hydrogen atom, G represents a hydrogen atom and a sulphate group, and the pharmaceutically acceptable salts of the said N,O-sulphated heparosans.

Abstract: The subject of the invention is new high molecular mass N,O-sulphated heparosans consisting of chains or of a mixture of chains having a molecular mass of between 1.5.times.10.sup.4 and 4.0.times.10.sup.6 D, characterised by a repeating disaccharide structure of formula I: ##STR1## in which E represents, in 0 to 80% of the disaccharide units of the said N,O-sulphated heparosan, an acetyl group and, in the remaining disaccharide units, a sulphate group and optionally a hydrogen atom, G represents a hydrogen atom and a sulphate group, and the pharmaceutically acceptable salts of the said N,O-sulphated heparosans.