Molecular properties and activity of amino-terminal truncated forms of lipase activator protein.
Two mutant forms, which had truncated N-terminals, of lipase activator protein (LipB) from Pseudomonas aeruginosa TE3285 were prepared, and their molecular properties and activity were compared with those of the full-length form. A truncated LipB lacking its hydrophobic N-terminal 21 residues was dispersed homogeneously in solution, and could reactivate the stoichiometric amount of denatured lipase. In contrast, full-length LipB formed soluble aggregates, and reactivated less than an equimolar amount of the lipase even under the most suitable conditions. These findings suggest that some or all of the N-terminal 21 residues caused aggregation of the protein molecules, and prevented LipB from fully stoichiometric reactivation. A truncated LipB lacking the N-terminal 61 residues also reactivated denatured lipase, suggesting that the N-terminal 61-residue region of LipB is not involved in reactivation.
Shibata
H
H
Institute for Chemical Research, Kyoto University, Japan.
Kato
H
H
Oda
J
J
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics; D002847:Chromatography, Agarose; D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D004789:Enzyme Activation; D004926:Escherichia coli / Q000737:chemistry; D008049:Lipase / Q000737:chemistry* / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D010957:Plasmids / Q000737:chemistry; D011550:Pseudomonas aeruginosa / Q000737:chemistry* / Q000235:genetics; D015534:Trans-Activators / Q000737:chemistry* / Q000235:genetics
D001426:Bacterial Proteins; C079999:LipA protein, Bacteria; D015534:Trans-Activators; C088618:lipase activator protein, Bacteria; D008049:Lipase