LIPAZY BAKTERII RODZAJÓW
PSEUDOMONAS I BURKHOLDERIA ORAZ
I CH WYKORZYSTANIE W BIOTECHNOLOGII
Agnieszka Mrozik, Katarzyna Hupert-Kocurek, Sylwia Łabużek
Katedra Biochemii Uniwersytetu Śląskiego ul Jagiellońska 28, 40-032 Katowice, e-mail:
amrozik@us.edu.pl
Wpłynęło w marcu 2006
1. Wstęp. 2. Budowa lipaz i mechanizm lipolizy. 3. Klasyfikacja
lipaz. 4. Mechanizmy regulacji syntezy lipaz. 5. Mechanizmy sekrecji i fałdowania lipaz. 6. Czynniki wpływające na syntezę
lipaz. 7. Lipazy w biotechnologii. 8. Podsumowanie
Lipases of genera Pseudomonas and Burkholderia and their applications in biotechnology
Abstract: Lipases (triacylglycerol acylhydrolases, EC 3.1.1.3) catalyze the hydrolysis and trans-esterification of triglycerides, enantioselective synthesis, and the hydrolysis of a variety of esters. According to their substrate specificity lipases are divided into three groups. The first group contains lipases showing no positional and no specificity to the chemical structure of fatty acid. Lipases of the second group hydrolyze only primary ester bonds while those of the third group exhibit a pronounced fatty acid preference. Lipases, in contrast to esterases, are activated only when absorbed to an oil-water interface and do not hydrolyze dissolved substrates in the bulk fluid. They are pro duce by many strains of bacteria, especially of the genus
Pseudomonas, Burkholderia, Acinetobacter and Staphylococcus and fungi, for example
Aspergillus terreus and Fusarium heterosporum. Microbial lipases have molecular weight of 19—60 kDa and are produced in the end of logarytmic phase of growth. All enzymes exhibit a characteristic folding patterm known as the alpha/beta-hydrolyze fold. Their active-site is composed of the catalytic triad serine, histidine and an acid residue, Asp or Glu. Based on seąuence of aminoacid,
Pseudomonas and Burkholderia lipases were classified into three families. Lipases from families I and II show more similarities, whereas family III lipases are larger (50 kDa) and untrelated to the other
lipases. All known bacterial lipases are extracellular enzymes requiring their translocation through the inner and outer membranes. Lipases of Pseudomonas are secreted by two types of secretion pathways: ABC exporters and general secretary pathway (GSP). Efficient secretion of lipases is coupled to correct folding. This process involves specific foldase and unspecific
Dsb-proteins. Because of their wide-ranging significance, lipases remain a subject of intensive studies. Researches of lipases are focused particularly on structural characterization, elucidation of mechanism of action, kineties, sequencing and cloning of lipase genes, folding and secrection. Lipases find promising applications in organie chemical processing, detergent production, synthesis of biosurfactants, the oleochemical industry, the dairy industry, the agrochemical
activity, paper manufacture, nutrition, cosmeties and pharmaceutical
processing.
1. Introduction. 2. Lipases structure and mechanism of
lipolysis. 3. Lipases classification. 4. Regulation of lipase
synthesis. 5. Mechanisms of secretion and lipase folding. 6. Factors affecting lipase
synthesis. 7. Lipases in biotechnology. 8. Summary
Słowa kluczowe: lipazy, Pseudomonas, Burkholderia, regulacja, wydzielanie
Key words: lipases, Pseudomonas, Burkholderia, regulation, secretion
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