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001-es BibID:	BIBFORM038085
Első szerző:	Li, Mi
Cím:	Structural and biochemical characterization of the inhibitor complexes of xenotropic murine leukemia virus-related virus protease / Li Mi, Gustchina Alla, Matúz Krisztina, Tözsér József, Namwong Sirilak, Goldfarb Nathan E., Dunn Ben M., Wlodawer Alexander
Dátum:	2011
ISSN:	1742-464X
Megjegyzések:	Interactions between the protease (PR) encoded by the xenotropic murine leukemia virus-related virus and a number of potential inhibitors have been investigated by biochemical and structural techniques. It was observed that several inhibitors used clinically against HIV PR exhibit nanomolar or even subnanomolar values of K(i) , depending on the exact experimental conditions. Both TL-3, a universal inhibitor of retroviral PRs, and some inhibitors originally shown to inhibit plasmepsins were also quite potent, whereas inhibition by pepstatin A was considerably weaker. Crystal structures of the complexes of xenotropic murine leukemia virus-related virus PR with TL-3, amprenavir and pepstatin A were solved at high resolution and compared with the structures of complexes of these inhibitors with other retropepsins. Whereas TL-3 and amprenavir bound in a predictable manner, spanning the substrate-binding site of the enzyme, two molecules of pepstatin A bound simultaneously in an unprecedented manner, leaving the catalytic water molecule in place.
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban Molekuláris Medicina
Megjelenés:	Febs Journal. - 278 : 22 (2011), p. 4413-4424. -
További szerzők:	Gustchina, Alla Matúz Krisztina (1980-) (vegyész, biokémikus) Tőzsér József (1959-) (molekuláris biológus, biokémikus, vegyész) Namwong, Sirilak Goldfarb, Nathan E. Dunn, Ben M. Wlodawer, Alexander
Pályázati támogatás:	TÁMOP-4.2.1/B-09/1/KONV-2010-0007 TÁMOP Retrovirális biokémia
Internet cím:	DOI Intézményi repozitóriumban (DEA) tárolt változat
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001-es BibID:	BIBFORM040695
Első szerző:	Tőzsér József (molekuláris biológus, biokémikus, vegyész)
Cím:	Studies on the role of the S4 substrate binding site of HIV proteinases / Tözsér József, Gustchina Alla, Weber Irene T., Blaha Ivo, Wondrak Ewald M., Oroszlan Stephen
Dátum:	1991
ISSN:	0014-5793
Megjegyzések:	Kinetic analysis of the hydrolysis of the peptide H-Val-Ser-Gln-Asn-Tyr*Pro-Ile-Val-Gln-NH2 and its analogs obtained by varying the length and introducing substitutions at the P4 site was carried out with both HIV-1 and HIV-2 proteinases. Deletion of the terminal Val and Gln had only moderate effect on the substrate hydrolysis, while the deletion of the P4. Ser as well as P'3 Val greatly reduced the substrate hydrolysis. This is predicted to be due to the loss of interactions between main chains of the enzyme and the substrate. Substitution of the P4 Ser by amino acids having high frequency of occurrence in beta turns resulted in good substrates, while large amino acids were unfavorable in this position. The two proteinases acted similarly, except for substrates having Thr, Val and Leu substitutions, which were better accommodated in the HIV-2 substrate binding pocket.
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:	Febs Letters. - 279 : 2 (1991), p. 356-360. -
További szerzők:	Gustchina, Alla Weber, Irene T. Bláha, Ivo Wondrak, Ewald M. Oroszlan, Stephen
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
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001-es BibID:	BIBFORM040684
Első szerző:	Tőzsér József (molekuláris biológus, biokémikus, vegyész)
Cím:	Kinetic and modeling studies of S3-S3' subsites of HIV proteinases / Tözsér J., Weber I. T., Gustchina A., Bláha I., Copeland T. D., Louis J. M., Oroszlan S.
Dátum:	1992
ISSN:	0006-2960
Megjegyzések:	Kinetic analysis and modeling studies of HIV-1 and HIV-2 proteinases were carried out using the oligopeptide substrate [formula: see text] and its analogs containing single amino acid substitutions in P3-P3' positions. The two proteinases acted similarly on the substrates except those having certain hydrophobic amino acids at P2, P1, P2', and P3' positions (Ala, Leu, Met, Phe). Various amino acids seemed to be acceptable at P3 and P3' positions, while the P2 and P2' positions seemed to be more restrictive. Polar uncharged residues resulted in relatively good binding at P3 and P2 positions, while at P2' and P3' positions they gave very high Km values, indicating substantial differences in the respective S and S' subsites of the enzyme. Lys prevented substrate hydrolysis at any of the P2-P2' positions. The large differences for subsite preference at P2 and P2' positions seem to be at least partially due to the different internal interactions of P2 residue with P1', and P2' residue with P1. As expected on the basis of amino acid frequency in the naturally occurring cleavage sites, hydrophobic residues at P1 position resulted in cleavable peptides, while polar and beta-branched amino acids prevented hydrolysis. On the other hand, changing the P1' Pro to other amino acids prevented substrate hydrolysis, even if the substituted amino acid had produced a good substrate in other oligopeptides representing naturally occurring cleavage sites. The results suggest that the subsite specificity of the HIV proteinases may strongly depend on the sequence context of the substrate.
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:	Biochemistry. - 31 : 20 (1992), p. 4793-4800. -
További szerzők:	Weber, Irene T. Gustchina, Alla Bláha, Ivo Copeland, Terry D. Louis, John M. Oroszlan, Stephen
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
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