Compositions and methods for the delivery of oxygen

摘要

H-NOX proteins are mutated to exhibit improved or optimal kinetic and thermodynamic properties for blood gas O2 delivery. The engineered H-NOX proteins comprise mutations that impart altered O2 or NO ligand-binding relative to the corresponding wild-type H-NOX domain, and are operative as physiologically compatible mammalian blood O2 gas carriers. The invention also provides pharmaceutical compositions, kits, and methods that use wild-type or mutant H-NOX proteins for the treatment of any condition for which delivery of O2 is beneficial.

主权项

1. An isolated H-NOX protein comprising at least one distal pocket mutation that alters the O2 dissociation constant or NO reactivity compared to that of a corresponding wild-type H-NOX protein, wherein the O2 dissociation constant of the mutant H-NOX protein is within 2 orders of magnitude of that of hemoglobin, wherein the NO reactivity of the mutant H-NOX protein is at least 10-fold lower than that of hemoglobin, wherein the H-NOX protein does not comprise a guanylyl cyclase catalytic domain, wherein the distal pocket mutation comprises a substitution at a residue that corresponds to at least one of Thr4, Ile5, Thr8, Trp9, Trp67, Asn74, Ile75, Phe78, Phe82, Tyr140, and Leu144 of a T. tengcongensis H-NOX of SEQ ID NO: 54, and wherein the mutant H-NOX protein is not T. tengcongensis H-NOX Y140L, T. tengcongensis H-NOX F78Y/Y140L, T. tengcongensis H-NOX W9F, T. tengcongensis H-NOX W9F/Y140L, H. sapiens β1 H-NOX (1-385) I145Y, or L. pneumophilia 2 H-NOX F142Y.