Cyanovirin variant-polymer conjugates
AssigneesNektar Therapeutics AL, Corporation, National Institute of Heatlh
InventorsM. Elizabeth Snell, Michael J. Roberts, Toshiyuki Mori, Barry R. O'Keefe, Michael R. Boyd
Life of this patent
Estimating the term…
Abstract
The present invention provides variants of cyanovirin-N and water-soluble polymer conjugates thereof, and methods of preparing such conjugates. The cyanovirin-N of the invention are particularly suited for site-selective covalent attachment of one or more water soluble polymers, to provide polymer conjugates of cyanovirin-N variants exhibiting antiviral activity.
Claims10
A method for preparing an antiviral polypeptide-polymer conjugate, comprising:
- (i) providing an antiviral polypeptide having at least 70% sequence identity to native cyanovirin-N (SEQ ID NO. 1), wherein said polypeptide is modified relative to SEQ ID NO:
- 1 to contain 1-4 reactive sites for selective conjugation, each said reactive site being selected from:
- (a) a cysteine substitution or insertion of at least one position selected from the group consisting of 5, 9-21, 25, 29-40, 45-49, 52, 57, 59-72, 79-91, 96-101 of SEQ ID NO:
- 1, the C-terminus, and the N-terminus;
- and
- (b) a single lysine residue remaining after arginine substitution of all but one of the lysine residues in the polypeptide;
- or a fragment thereof, wherein the fragment includes the sequence set forth in residues 40-80 of SEQ ID NO:
- 1, modified to contain at least one said reactive site for selective conjugation;
- and
- (ii) covalently attaching thereto, at at least one said reactive site for selective conjugation, a water-soluble polymer,
- wherein said antiviral polypeptide-polymer conjugate has antiviral activity.
An antiviral polypeptide having at least 70% sequence identity to native cyanovirin-N (SEQ ID NO. 1) and having fewer than ten non-conservative amino acid substitutions relative to native cyanovirin-N (SEQ ID NO. 1), wherein said polypeptide is modified relative to SEQ ID NO:
- 1 to contain 1-4 reactive sites for selective conjugation, each said reactive site being selected from:
- (a) a cysteine substitution or insertion of at least one position selected from the group consisting of 5, 9-21, 25, 29-40, 45-49, 52, 57, 59-72, 79-91, 96-101 of SEQ ID NO:
- 1, the C-terminus, and the N-terminus;
- and
- (b) a single lysine residue remaining after arginine substitution of all but one of the lysine residues in the polypeptide;
- or a fragment thereof, wherein the fragment includes the sequence set forth in residues 40-80 of SEQ ID NO:
- 1, modified to contain at least one said reactive site for selective conjugation.
Dependencies are inferred from the claim text.