Fosfolipaza
Fosfolipaza je enzim koji hidrolizuje fosfolipide[1] u masne kiseline i druge lipofilne supstance.[2] Postoje četiri glavne klase, koje se označavaju A, B, C i D. One se razlikuju po tipu reakcije koju katalizuju:
- Fosfolipaza A
- Fosfolipaza A1 - razlaže SN-1 acilni lanac.
- Fosfolipaza A2 - razlaže SN-2 acilni lanac, oslobađajući arahidonsku kiselinu.
- Fosfolipaza B - razlaže SN-1 i SN-2 acil lance; ovaj enzim je poznat i kao lizofosfolipaza.
- Fosfolipaza C - razlaže ispred fosfata, oslobađajući diacilglicerol i čeonu grupu sa fosfatom. Fosfolipaze C imaju centralnu ulogu u prenosu signala, jer oslobađaju sekundarni glasnik inozitol trifosfat.
- Fosfolipaza D - razlaže iza fosfata, oslobađajući fosfatidilnu kiselinu i alkohol.
Mesta razlaganja fosfolipazom. Enzim koji ima PLA1 i PLA2 aktivnosti se naziva Fosfolipaza B.
Tipovi C i D se smatraju fosfodiesterazama.
Fosfolipaza A2 deluje na lecitinski molekul, pri čemu hidrolizuje masnu kiselinu esterifikovanu na drugom atomu ugljenika. Rezultujući proizvodi su lizolecitin i masna kiselina. Fosfolipaza A2 je enzim koji je prisutan u otrovu pčela i zmija.[3]
ReferenceUredi
- ↑ "Phospholipase at Dorland's Medical Dictionary". http://www.mercksource.com/pp/us/cns/cns_hl_dorlands_split.jsp?pg=/ppdocs/us/common/dorlands/dorland/six/000081983.htm.
- ↑ Donald Voet, Judith G. Voet (2005). Biochemistry (3 izd.). Wiley. ISBN 978-0-471-19350-0. http://www.chem.upenn.edu/chem/research/faculty.php?browse=V.
- ↑ D. M. Vasudevan & S. Sreekumari, Textbook of Biochemistry (5th ed.)
LiteraturaUredi
- Nicholas C. Price, Lewis Stevens (1999). Fundamentals of Enzymology: The Cell and Molecular Biology of Catalytic Proteins (Third izd.). USA: Oxford University Press. ISBN 019850229X. http://books.google.com/books/about/Fundamentals_of_enzymology.html?id=8uvwAAAAMAAJ.
- Eric J. Toone (2006). Advances in Enzymology and Related Areas of Molecular Biology, Protein Evolution (Volume 75 izd.). Wiley-Interscience. ISBN 0471205036. http://books.google.com/books/about/Advances_in_Enzymology_and_Related_Areas.html?id=Pmh8yToeuloC.
- Branden C, Tooze J.. Introduction to Protein Structure. New York, NY: Garland Publishing. ISBN: 0-8153-2305-0. http://www.garlandscience.com/textbooks/0815323042.asp?type=reviews.
- Irwin H. Segel. Enzyme Kinetics: Behavior and Analysis of Rapid Equilibrium and Steady-State Enzyme Systems (Book 44 izd.). Wiley Classics Library. ISBN 0471303097. http://books.google.com/books/about/Enzyme_Kinetics.html?id=T60oAAAAYAAJ.
- Robert A. Copeland (2013). Evaluation of Enzyme Inhibitors in Drug Discovery: A Guide for Medicinal Chemists and Pharmacologists (2nd izd.). Wiley-Interscience. ISBN 111848813X. http://books.google.com/books/about/Evaluation_of_Enzyme_Inhibitors_in_Drug.html?id=l2rMy8QNUk0C.
- Gerhard Michal, Dietmar Schomburg (2012). Biochemical Pathways: An Atlas of Biochemistry and Molecular Biology (2nd izd.). Wiley. ISBN 0470146842. http://books.google.com/books/about/Biochemical_pathways.html?id=081qAAAAMAAJ.
