Lipolytic enzymes of the digestive organs of the crown-of-thorns starfish (Acanthaster planci): comparison of the stomach and pyloric caeca.
1. Stomach and pyloric caeca homogenates from the crown-of-thorns starfish hydrolysed p-nitrophenyl esters, alpha-naphthyl esters, cholesteryl oleate and tributyrin. The pyloric caeca contained the highest activities. 2. The p-nitrophenyl acetate hydrolytic activity eluted at 0.23 M NaCl on ion exchange chromatography while the p-nitrophenyl palmitate hydrolytic activity eluted between 0.2 and 1.0 M NaCl. 3. Polyacrylamide gel zymograms for alpha-naphthyl acetate hydrolytic activity revealed one major band and several minor bands of activity for both tissues. 4. Isoelectric focusing zymograms revealed one major band with a pI = 4.2 for both tissues, with an additional band at pI = 3.5 for pyloric caeca. 5. The pyloric caeca contained twice as much lipid as the stomach. Lipid extracts contained mixtures of steroids and steroid-esters; a cholesterol-like sterol was tentatively identified.
Brahimi-Horn
M C
MC
Commonwealth Scientific and Industrial Research Organisation, Division of Wool Technology, Parkville, Vic. Australia.
Guglielmino
M L
ML
Sparrow
L G
LG
Logan
R I
RI
Moran
P J
PJ
D000818:Animals; D002432:Cecum / Q000032:analysis*; D002852:Chromatography, Ion Exchange; D004591:Electrophoresis, Polyacrylamide Gel; D004950:Esterases / Q000032:analysis*; D007525:Isoelectric Focusing; D008049:Lipase / Q000032:analysis*; D008055:Lipids / Q000302:isolation & purification; D013215:Starfish / Q000378:metabolism*; D002787:Sterol Esterase / Q000032:analysis; D013270:Stomach / Q000032:analysis*; D013379:Substrate Specificity
D008055:Lipids; D004950:Esterases; D002787:Sterol Esterase; D008049:Lipase