Proteaza
Proteaza (peptidaza, proteinaza) je enzim koji izvodi proteolizu. Proteaza započinje proteinski katabolizam hidrolizom peptidnih veza koje povezuju aminokiseline u polipeptidne lance od kojih je formiran protein.[1][2]
Klasifikacija
urediStandard
urediProteaze se dele u šest grupa:
- Serinske proteaze
- Treoninske proteaze
- Cisteinske proteaze
- Aspartatne proteaze
- Metaloproteaze
- Glutamatne proteaze
Treoninske i glutamatne proteaze nisu bile poznate do 1995 i 2004, respektivno. Mehanizam raskidanja peptidne veze obuhvata korak u kome nukleofil napada peptidnu vezu. Nukleofil je bilo aminokiselina peptidaze (cistein, serin, treonin) ili molekul vode kod aspartat-, metalo- i glutamatne proteaze. Jedan način formiranja nukleofila je putem katalitičke trijade, gde se histidinski ostatak koristi za aktivaciju serina, cisteina, ili treonina.
Reference
uredi- ↑ Donald Voet, Judith G. Voet (2005). Biochemistry (3 izd.). Wiley. ISBN 978-0-471-19350-0.
- ↑ Branden C, Tooze J.. Introduction to Protein Structure. New York, NY: Garland Publishing. ISBN: 0-8153-2305-0.
Literatura
uredi- Barrett A.J., Rawlings ND, Woessner JF. The Handbook of Proteolytic Enzymes, 2nd ed. Academic Press, 2003. ISBN 0-12-079610-4.
- Hedstrom L. Serine Protease Mechanism and Specificity. Chem Rev 2002;102:4501-4523.
- Southan C. A genomic perspective on human proteases as drug targets. Drug Discov Today 2001;6:681-688.
- Hooper NM. Proteases in Biology and Medicine. London: Portland Press, 2002. ISBN 1-85578-147-6.
- Puente XS, Sanchez LM, Overall CM, Lopez-Otin C. Human and Mouse Proteases: a Comparative Genomic Approach. Nat Rev Genet 2003;4:544-558.
- Ross J, Jiang H, Kanost MR, Wang Y. Serine proteases and their homologs in the Drosophila melanogaster genome: an initial analysis of sequence conservation and phylogenetic relationships. Gene 2003;304:117-31.
- Puente XS, Lopez-Otin C. A Genomic Analysis of Rat Proteases and Protease Inhibitors. Genome Biol 2004;14:609-622.
- Lucía Feijoo-Siota, Tomás G. Villa Native and Biotechnologically Engineered Plant Proteases with Industrial Applications. Food and Bioprocess Technology 2010.