摘要:
The tetrapeptide Phe-Asn-Pro-Arg (SEQ ID NO: 3) is a structurally-optimized sequence for binding to the active site of thrombin. By conjugating this tetrapeptide or variants thereof to a C-terminal fragment of hirudin, we were able to generate a series of new multivalent inhibitors of thrombin containing only genetically encodable natural amino acids. We found that synergistic binding to both the active site and an exosite of thrombin can be enhanced through substitutions of amino acid residues at the P4, P3 and P3′ sites of the active-site directed sequence, Xaa (P4)-Yaa (P3)-Pro (P2)-Arg (P1)-Pro(P1′)-Gln(P2′)-Zaa(P3′). Complementary to rational design, a phage library was constructed to explore further the residue requirements at the P4, P3 and P3′ sites for multivalent and optimized bridge-binding. Panning of the phage library has led to thrombin-inhibitory peptides possessing strong anti-cloning activities in the low nanomolar range and yet interfering only partially with the catalytic active site of thrombin. In all, the availability of potent and genetically-encodable polypepticle inhibitors of thrombin opens the door for much wider applications of this clinically-successful class of anticoagulants, e.g. through more cost-effective recombinant peptide production, in areas such as gene therapy as well as to improve clinical efficacy/safety through the incorporation of homing peptides for targeted delivery.
摘要:
The tetrapeptide Phe-Asn-Pro-Arg is a structurally-optimized sequence for binding to the active site of thrombin. By conjugating this tetrapeptide or variants thereof to a C-terminal fragment of hirudin, we were able to generate a series of new multivalent inhibitors of thrombin containing only genetically encodable natural amino acids. We found that synergistic binding to both the active site and an exosite of thrombin can be enhanced through substitutions of amino acid residues at the P4, P3 and P3′ sites of the active-site directed sequence, Xaa(P4)-Yaa(P3)-Pro(P2)-Arg(P1)-Pro(P1′)-Gln(P2′)-Zaa(P3′). Complementary to rational design, a phage library was constructed to explore further the residue requirements at the P4, P3 and P3′ sites for multivalent and optimized bridge-binding. Panning of the phage library has led to thrombin-inhibitory peptides possessing strong anti-clotting activities in the low nanomolar range and yet interfering only partially with the catalytic active site of thrombin. In all, the availability of potent and genetically-encodable polypeptide inhibitors of thrombin opens the door for much wider applications of this clinically-successful class of anticoagulants, e.g. through more cost-effective recombinant peptide production, in areas such as gene therapy as well as to improve clinical efficacy/safety through the incorporation of homing peptides for targeted delivery.
摘要:
The tetrapeptide Phe-Asn-Pro-Arg (SEQ ID NO: 3) is a structurally-optimized sequence for binding to the active site of thrombin. By conjugating this tetrapeptide or variants thereof to a C-terminal fragment of hirudin, we were able to generate a series of new multivalent inhibitors of thrombin containing only genetically encodable natural amino acids. We found that synergistic binding to both the active site and an exosite of thrombin can be enhanced through substitutions of amino acid residues at the P4, P3 and P3′ sites of the active-site directed sequence, Xaa (P4)-Yaa (P3)-Pro (P2)-Arg (P1)-Pro(P1′)-Gln(P2′)-Zaa(P3′). Complementary to rational design, a phage library was constructed to explore further the residue requirements at the P4, P3 and P3′ sites for multivalent and optimized bridge-binding. Panning of the phage library has led to thrombin-inhibitory peptides possessing strong anti-clotting activities in the low nanomolar range and yet interfering only partially with the catalytic active site of thrombin. In all, the availability of potent and genetically-encodable polypeptide inhibitors of thrombin opens the door for much wider applications of this clinically-successful class of anticoagulants, e.g. through more cost-effective recombinant peptide production, in areas such as gene therapy as well as to improve clinical efficacy/safety through the incorporation of homing peptides for targeted delivery.
摘要翻译:四肽Phe-Asn-Pro-Arg(SEQ ID NO:3)是结合到凝血酶活性位点的结构优化的序列。 通过将这种四肽或其变体与水蛭素的C末端片段缀合,我们能够产生一系列含有仅基因可编码天然氨基酸的凝血酶的新型多价抑制剂。 我们发现通过在活性位点定向序列Xaa(P4)-Yaa(P3)的P4,P3和P3'位点处的氨基酸残基的取代可以增强与凝血酶的活性位点和外部位点的协同结合, -Pro(P2)-Arg(P1)-Pro(P1')-G1n(P2')-Zaa(P3')。 与理性设计相辅相成,构建了噬菌体文库,进一步探索P4,P3和P3位点的残留要求,进行多价和优化的桥接。 噬菌体文库的淘选导致凝血酶抑制肽在低纳摩尔范围内具有强烈的抗凝血活性,但仅部分地与凝血酶的催化活性位点相互干扰。 总之,有效的和可遗传编码的凝血酶多肽抑制剂的可用性为这种临床上成功的一类抗凝剂的应用开辟了广泛的应用。 通过在基因治疗等领域通过更具成本效益的重组肽生产,以及通过并入用于靶向递送的归巢肽来提高临床疗效/安全性。
摘要:
There is provided a method of quantitatively ranking transient ligand binding to target biomolecules by means of NMR relaxation dispersion profiles. The present invention also relates to a method to identify ligand site obeying two-state and more complex binding behavior in a transient complex of a ligand with a target molecule, still with the use of NMR. There is also provided an efficient method to quantitate fast dissociation rates of ligands containing at least one magnetic nuclei by performing NMR relaxation dispersion experiments at different protein concentrations, enabling the evaluation of populations and exchange rates, and extending the practical applicability of the NMR relaxation dispersion experiments.
摘要:
A locally-activatable bivalent thrombin binding agent is provided having two thrombin binding moieties for non-overlapping sites on a surface of thrombin linked together by a linker. The linker is a polypeptide having 5 to 30 amino acid residues existing in a folded state under an environmental condition where the binding agent is inactive. The linker changes conformation from the folded state to an unfolded state in response to a change in bulk temperature and/or to the presence of hyper-mobile water thereby activating the binding agent. Such locally-activatable thrombin binding agents can be administered systemically while only targeting specific sites of coagulation or inflammation since the thrombin binding agent will only activate at the site where the existence of atherosclerotic plaques has changed the local bulk temperature and/or created hyper-mobile water sufficiently to unfold the linker and activate the binding agent. Such binding agents are useful as site-specific anti-coagulant, anti-thrombotic and/or antiinflammatory agents.
摘要:
A locally-activatable bivalent thrombin binding agent is provided having two thrombin binding moieties for non-overlapping sites on a surface of thrombin linked together by a linker. The linker is a polypeptide having 5 to 30 amino acid residues existing in a folded state under an environmental condition where the binding agent is inactive. The linker changes conformation from the folded state to an unfolded state in response to a change in bulk temperature and/or to the presence of hyper-mobile water thereby activating the binding agent. Such locally-activatable thrombin binding agents can be administered systemically while only targeting specific sites of coagulation or inflammation since the thrombin binding agent will only activate at the site where the existence of atherosclerotic plaques has changed the local bulk temperature and/or created hyper-mobile water sufficiently to unfold the linker and activate the binding agent. Such binding agents are useful as site-specific anti-coagulant, anti-thrombotic and/or antiinflammatory agents.
摘要:
There is provided herein a multivalent binding molecule and uses thereof. The molecule is useful in binding a target under certain conditions and releasing it under other conditions. The molecule has the general formula (1) of BM1-L-(BM2)n (1) wherein, BM1 is a binding moiety 1 having an affinity for site 1 on the target, BM2 is a binding moiety 2 having an affinity for a site other than site 1 on the target, n is 1 or greater, and L is a linker joining BM1 and BM2, said linker being adapted to respond to a change in its environment with a change in conformation and/or flexibility, wherein BM1 and BM2 may be the same or different and are selected such that in use each of the BM1 and BM2 existing separately has a lower binding affinity then the complex of BM1 and BM2 does when they are linked to form the molecule. BM2 may have a single binding region or multiple binding regions with affinity for the target. The binding affinity of BM1 or BM2 to the target alone is no more than ½ the binding affinity of the molecule of formula (1). The molecule of formula (1) can be constructed using an oligomeric or polymeric linker, such as a polypeptide sequence. Such molecules can be useful in the delayed release of drugs, in screening assays, for stabilizing enzymes such as proteases, and for controlling reactions such as blood clotting.
摘要:
There is provided herein a multivalent binding molecule and uses thereof. The molecule is useful in binding a target under certain conditions and releasing it under other conditions. The molecule has the general formula (1) of BM1-L-(BM2)n (1) wherein, BM1 is a binding moiety 1 having an affinity for site 1 on the target, BM2 is a binding moiety 2 having an affinity for a site other than site 1 on the target, n is 1 or greater, and L is a linker joining BM1 and BM2, said linker being adapted to respond to a change in its environment with a change in conformation and/or flexibility, wherein BM1 and BM2 may be the same or different and are selected such that in use each of the BM1 and BM2 existing separately has a lower binding affinity then the complex of BM1 and BM2 does when they are linked to form the molecule. BM2 may have a single binding region or multiple binding regions with affinity for the target. The binding affinity of BM1 or BM2 to the target alone is no more than ½ the binding affinity of the molecule of formula (1). The molecule of formula (1) can be constructed using an oligomeric or polymeric linker, such as a polypeptide sequence. Such molecules can be useful in the delayed release of drugs, in screening assays, for stabilizing enzymes such as proteases, and for controlling reactions such as blood clotting.