Lipase-colipase complex

For an example of neutron diffraction applied to a crystallographic problem, see D. Pignol, J. Hermoso, B. Kerfelec, I. Crenon, C. Chapus, and J. C. Fontecilla-Camps, The lipase/colipase complex is activated by a micelle Neutron crystallographic evidence, Chem. Phys. Lipids 93, 123-129, 1998. 

Egloff, M.-P., Marguet, F., Buono, G., Verger, R., Cambillau, C. and van Tilbeurgh, H. (1995) The 2.46 A resolution structure of the pancreatic lipase-colipase complex inhibited by a Cu alkyl phosphonate. Biochemistry 34, 2751-2762... 

Topical pancreatic lipase substrates like tributyrin and triolein emulsions are hydrolyzed by carboxylester lipase in the presence of bile salt but slowly—at a rate lower than 3% and 0.5%, respectively, of that observed with the lipase-colipase complex. On the other hand, the positional specificity is not restricted all three sn positions of triglycerides can be split by the carboxylester lipase. While long-chain phospholipids are resistant, short-chain phospholipids are readily attacked by carboxylester lipase [40]. The low substrate specificity of carboxylester lipase makes possible an essential role for this enzyme in the hydrolysis of triglycerides containing certain esterified polyunsaturated fatty acids, such as eicosapentaenoic, arachidonic, or linoleic acids [41], and which may be resistant to attack by pancreas lipase (see p. 190). 

FIG. 3 Structure of human pancreatic lipase-colipase complex in the closed conformation (E), and structure of the complex in the open conformation (E S). These two figures show the conformational changes in the lid, the 35-loop, and the cohpase during... 

Figure 3 shows the structure of the HPL-colipase complex [30,34]. Human pancreatic lipase consists of 449 amino acid residues and has 85% homology with that of porcine pancreatic lipase. Two distinct domain exists in HPL, that is, a larger N-terminal domain (N-domain) comprising 1-335 residues and a smaller C-terminal domain (C-domain). Of these domains, the N-domain con-... 

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