scholarly journals The acid lipase of the castor bean. Properties and substrate specificity

1962 ◽  
Vol 3 (1) ◽  
pp. 99-105
Author(s):  
Robert L. Ory ◽  
Allen J. St. Angelo ◽  
Aaron M. Altschul
Keyword(s):  
Substrate Specificity ◽  
Castor Bean ◽  
Acid Lipase

Castor-bean acid lipase catalysed hydrolysis of triacylglycerols does not involve C-2 → C-1,3 transacylation

1985 ◽  
Vol 23 (12) ◽  
pp. 3047-3048
Author(s):  
T Diez
Keyword(s):  
Castor Bean ◽  
Acid Lipase ◽  
Hydrolysis Of

Studies on positional specificity of the castor bean acid lipase

Lipids ◽  
1969 ◽  
Vol 4 (4) ◽  
pp. 261-264 ◽  
Author(s):  
Robert L. Ory ◽  
James Kiser ◽  
Paul A. Pradel
Keyword(s):  
Castor Bean ◽  
Acid Lipase ◽  
Positional Specificity

Acid Lipase of Castor Bean Lipid Bodies : Isolation and Characterisation

1997 ◽  
Vol 6 (1) ◽  
pp. 13-18 ◽  
Author(s):  
A. Altaf ◽  
T. V. Ankers ◽  
N. Kaderbhai ◽  
E. I. Mercer ◽  
M. A. Kaderbhai
Keyword(s):  
Castor Bean ◽  
Lipid Bodies ◽  
Acid Lipase

scholarly journals Cysteine residues in human lysosomal acid lipase are involved in selective cholesteryl esterase activity

1997 ◽  
Vol 326 (1) ◽  
pp. 265-269 ◽  
Author(s):  
Franco PAGANI ◽  
Rajalakshmi PARIYARATH ◽  
Cristiana STUANI ◽  
Rodolfo GARCIA ◽  
Francisco E. BARALLE
Keyword(s):  
Amino Acid ◽  
Substrate Specificity ◽  
Single Amino Acid ◽  
Cysteine Residues ◽  
Variable Degree ◽  
Acid Lipase ◽  
T7 Promoter ◽  
Lysosomal Acid ◽  
Lysosomal Acid Lipase ◽  
Catalytic Active Site

Human lysosomal acid lipase (LAL) catalyses the deacylation of triacylglycerol and cholesteryl esters in the acidic lysosomal compartment. Treatment of LAL with the reducing agent dithiothreitol affected the triacylglycerol and cholesteryl esterase activities differentially, suggesting the involvement of cysteine residues in determining substrate specificity. To identify the residues involved, human LAL cDNA, under the control of the T7 promoter and tagged with a herpes simplex virus coding epitope, was specifically mutated in order to introduce single amino acid substitutions of each of the six cysteine residues of mature LAL. All Cys-227 mutants showed selectively decreased activity towards cholesteryl oleate, while preserving that towards trioleylglycerol. Substitutions of Cys-236, Cys-240 and Cys-244 affected catalysis towards the two substrates to a variable degree, depending on the side chain of the amino acid introduced. The replacement of Cys-41 or Cys-188 did not result in the preferential cleavage of either one of the two substrates. These data indicate that Cys-227, Cys-236, Cys-240 and Cys-244 play a crucial role in determining LAL substrate specificity. We propose that these cysteine residues are involved in the hydrolysis of cholesteryl ester by affecting selectively the access of this substrate to the catalytic active site. In addition, the fact that the catalytic activity is never completely abolished in cysteine mutants demonstrates that LAL is not a thiol enzyme.

Castor-bean acid lipase catalysed hydrolysis of triacylglycerols does not involve C-2 → C-1,3 transacylation

1985 ◽  
Vol 24 (12) ◽  
pp. 3047-3048 ◽  
Author(s):  
Tomás A. Diez ◽  
Julio F. Mata-Segreda
Keyword(s):  
Castor Bean ◽  
Acid Lipase ◽  
Hydrolysis Of

Acid lipase of the castor bean

Lipids ◽  
1969 ◽  
Vol 4 (3) ◽  
pp. 177-185 ◽  
Author(s):  
Robert L. Ory
Keyword(s):  
Castor Bean ◽  
Acid Lipase

A lipid cofactor for the acid lipase of the castor bean

1962 ◽  
Vol 7 (5) ◽  
pp. 375-379 ◽  
Author(s):  
Robert L. Ory ◽  
Aaron M. Altschul
Keyword(s):  
Castor Bean ◽  
Acid Lipase

Substrate specificity and inducibility of TACE (tumour necrosis factor α-converting enzyme) revisited: the Ala-Val preference, and induced intrinsic activity

2003 ◽  
Vol 70 ◽  
pp. 39-52 ◽  
Author(s):  
Roy A. Black ◽  
John R. Doedens ◽  
Rajeev Mahimkar ◽  
Richard Johnson ◽  
Lin Guo ◽  
...  
Keyword(s):  
Substrate Specificity ◽  
Recent Work ◽  
Tumour Necrosis Factor ◽  
Tumour Necrosis ◽  
Transforming Growth Factor ◽  
Intrinsic Activity ◽  
Converting Enzyme ◽  
Tumour Necrosis Factor Α ◽  
Factor Α ◽  
Necrosis Factor

Tumour necrosis factor α (TNFα)-converting enzyme (TACE/ADAM-17, where ADAM stands for a disintegrin and metalloproteinase) releases from the cell surface the extracellular domains of TNF and several other proteins. Previous studies have found that, while purified TACE preferentially cleaves peptides representing the processing sites in TNF and transforming growth factor α, the cellular enzyme nonetheless also sheds proteins with divergent cleavage sites very efficiently. More recent work, identifying the cleavage site in the p75 TNF receptor, quantifying the susceptibility of additional peptides to cleavage by TACE and identifying additional protein substrates, underlines the complexity of TACE-substrate interactions. In addition to substrate specificity, the mechanism underlying the increased rate of shedding caused by agents that activate cells remains poorly understood. Recent work in this area, utilizing a peptide substrate as a probe for cellular TACE activity, indicates that the intrinsic activity of the enzyme is somehow increased.

Substrate specificity sleuths

2012 ◽  
Author(s):  
Barbara Potts
Keyword(s):  
Substrate Specificity
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