Substrate specificity and kinetic properties of enzymes belonging to the hormone-sensitive lipase family: comparison with non-lipolytic and lipolytic carboxylesterases.
We have studied the kinetics of hydrolysis of triacylglycerols, vinyl esters and p-nitrophenyl butyrate by four carboxylesterases of the HSL family, namely recombinant human hormone-sensitive lipase (HSL), EST2 from Alicyclobacillus acidocaldarius, AFEST from Archeoglobus fulgidus, and protein RV1399C from Mycobacterium tuberculosis. The kinetic properties of enzymes of the HSL family have been compared to those of a series of lipolytic and non-lipolytic carboxylesterases including human pancreatic lipase, guinea pig pancreatic lipase related protein 2, lipases from Mucor miehei and Thermomyces lanuginosus, cutinase from Fusarium solani, LipA from Bacillus subtilis, porcine liver esterase and Esterase A from Aspergilus niger. Results indicate that human HSL, together with other lipolytic carboxylesterases, are active on short chain esters and hydrolyze water insoluble trioctanoin, vinyl laurate and olive oil, whereas the action of EST2, AFEST, protein RV1399C and non-lipolytic carboxylesterases is restricted to solutions of short chain substrates. Lipolytic and non-lipolytic carboxylesterases can be differentiated by their respective value of K(0.5) (apparent K(m)) for the hydrolysis of short chain esters. Among lipolytic enzymes, those possessing a lid domain display higher activity on tributyrin, trioctanoin and olive oil suggesting, then, that the lid structure contributes to enzyme binding to triacylglycerols. Progress reaction curves of the hydrolysis of p-nitrophenyl butyrate by lipolytic carboxylesterases with lid domain show a latency phase which is not observed with human HSL, non-lipolytic carboxylesterases, and lipolytic enzymes devoid of a lid structure as cutinase.
Chahinian
Henri
H
Laboratoire d'Enzymologie Interfaciale et de Physiologie de la lipolyse, UPR9025-CNRS, 31 Chemin J. Aiguier, 13402 Marseille Cedex 20, France. chahin@ibsm.cnrs-mrs.fr
Ali
Yassine Ben
YB
Abousalham
Abdelkarim
A
Petry
Stefan
S
Mandrich
Luigi
L
Manco
Guiseppe
G
Canaan
Stephane
S
Sarda
Louis
L
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D002087:Butyrates / Q000378:metabolism; D002210:Caprylates / Q000378:metabolism; D002265:Carboxylic Ester Hydrolases / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007700:Kinetics; D008049:Lipase / Q000378:metabolism; D008969:Molecular Sequence Data; D000069463:Olive Oil; D010938:Plant Oils / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D002787:Sterol Esterase / Q000378:metabolism*; D013379:Substrate Specificity; D014280:Triglycerides / Q000378:metabolism; D014753:Vinyl Compounds / Q000378:metabolism
D001426:Bacterial Proteins; D002087:Butyrates; D002210:Caprylates; C079999:LipA protein, Bacteria; D000069463:Olive Oil; D010938:Plant Oils; D011994:Recombinant Proteins; D014280:Triglycerides; D014753:Vinyl Compounds; C095498:vinyl butyrate; C033592:4-nitrophenyl butyrate; C003637:tricaprylin; D002265:Carboxylic Ester Hydrolases; C493188:Rv1399c protein, M tuberculosis; C019952:cutinase; D002787:Sterol Esterase; D008049:Lipase; C075988:pancreatic lipase related protein 2; C005830:tributyrin