Purification and Characterization of a Cysteine Endopeptidase fromVasconcellea quercifoliaA. St.-Hil. Latex Displaying High Substrate Specificity

2010 ◽  
Vol 58 (20) ◽  
pp. 11027-11035 ◽  
Author(s):  
M. José Torres ◽  
Sebastián A. Trejo ◽  
M. Inés Martin ◽  
Claudia L. Natalucci ◽  
Francesc X. Avilés ◽  
...  
Keyword(s):  
Substrate Specificity ◽  
Purification And Characterization ◽  
High Substrate ◽  
Cysteine Endopeptidase

Purification and characterization of a post-proline dipeptidyl aminopeptidase fromStreptococcus cremorisAM2

1990 ◽  
Vol 57 (1) ◽  
pp. 89-99 ◽  
Author(s):  
Mary Booth ◽  
Ide Ni Fhaoláin ◽  
P. Vincent Jennings ◽  
Gerard O'Cuinn
Keyword(s):  
Molecular Weight ◽  
Amino Acid ◽  
Substrate Specificity ◽  
Purification And Characterization ◽  
Ph Optimum ◽  
Cheese Ripening ◽  
Streptococcus Cremoris ◽  
Scissile Bond ◽  
Dipeptidyl Aminopeptidase

SummaryThe present study describes the purification of a post-proline dipeptidyl aminopeptidase from the cytoplasm ofStreptococcus cremorisAM2. On the basis of its elution from a calibrated Sephadex G200 column, the enzyme had a molecular weight of 117000 and exhibited a broad pH optimum activity between 6·0 and 9·0. The activity was most comprehensively inhibited by phenylmethylsulphonylfluoride and more modestly inhibited by 1,10-phenanthroline and 8-hydroxyquinoline but not by EDTA. A range of peptides containing either proline or alanine as the penultimate amino acid residue could act as substrates. The presence of proline on the carboxy side of the scissile bond prevented hydrolysis. However the enzyme could release Pro-Pro from Pro-Pro-Gly-Phe-Ser-Pro. The significance of this substrate specificity is considered in the context of removal of either single proline residues or prolylproline sequences from oligopeptides during cheese ripening.

scholarly journals A Boophilus microplus vitellin-degrading cysteine endopeptidase

Parasitology ◽  
2003 ◽  
Vol 126 (2) ◽  
pp. 155-163 ◽  
Author(s):  
A. SEIXAS ◽  
P. C. DOS SANTOS ◽  
F. F. VELLOSO ◽  
I. DA SILVA VAZ ◽  
A. MASUDA ◽  
...  
Keyword(s):  
Ion Exchange ◽  
Gel Filtration ◽  
Exchange Chromatography ◽  
Boophilus Microplus ◽  
Hard Tick ◽  
Purification And Characterization ◽  
Basic Residue ◽  
Cysteine Endopeptidase ◽  
Sds Page

Here we describe the purification and characterization of a vitellin (VT) degrading cysteine endopeptidase (VTDCE) from eggs of the hard tick Boophilus microplus. A homogeneous enzyme preparation was obtained by chromatographic fractionation on ion-exchange and gel filtration columns and an autolysis step. This step consisted of incubation of a semipurified enzyme (after the first ion-exchange chromatography) at pH 4·0 that dissociated the enzyme from VT, to which VTDCE is naturally tightly associated. The enzyme purity was confirmed by capillary and native gel electrophoresis, and SDS–PAGE suggested the enzyme is a dimer of 17 and 22 kDa. VTDCE was active upon several synthetic substrates, with a preference for a hydrophobic or a basic residue in P1, and a hydrophobic residue in P2. VTDCE also hydrolysed haemoglobin, albumin, gelatin and vitellin. VTDCE is inactive in the absence of DTT and was totally inhibited by E-64, indicating it is a cysteine endopeptidase. Our results suggest that VTDCE is a major enzyme involved in yolk processing during B. microplus embryogenesis.

scholarly journals Purification and characterization of UDP-glucose: hydroxycoumarin 7-O-glucosyltransferase, with broad substrate specificity from tobacco cultured cells

Plant Science ◽  
2000 ◽  
Vol 157 (1) ◽  
pp. 105-112 ◽  
Author(s):  
Goro Taguchi ◽  
Hirofumi Imura ◽  
Yoshio Maeda ◽  
Ritsuko Kodaira ◽  
Nobuaki Hayashida ◽  
...  
Keyword(s):  
Substrate Specificity ◽  
Cultured Cells ◽  
Purification And Characterization ◽  
Broad Substrate Specificity

scholarly journals The purification and characterization of acetoacetyl-coenzyme A reductase from Azotobacter beijerinckii

1971 ◽  
Vol 121 (2) ◽  
pp. 309-316 ◽  
Author(s):  
G. A. F. Ritchie ◽  
P. J. Senior ◽  
E. A. Dawes
Keyword(s):  
Substrate Specificity ◽  
Reaction Rate ◽  
Acyl Carrier Protein ◽  
Thiol Group ◽  
Carrier Protein ◽  
Purification And Characterization ◽  
Michaelis Constants ◽  
Coa Reductase ◽  
Acetoacetyl Coa Reductase

A soluble acetoacetyl-CoA reductase (EC 1.1.1.36) was purified 54-fold from Azotobacter beijerinckii N.C.I.B. 9067 and the reaction product identified as d(−)-β-hydroxybutyryl-CoA. The Michaelis constants for acetoacetyl-CoA, NADPH and NADH were determined and the reaction rate was found to be some fivefold greater with NADPH than with NADH. At neutral pH the equilibrium greatly favours the formation of the reduced product. Substrate specificity was in the order: acetoacetyl-CoA>acetoacetylpantetheine>acetoacetyl-(acyl-carrier protein). The enzyme possesses a functional thiol group, suffers inactivation by oxygen and is inhibited by thiol-blocking reagents. Inhibition by p-chloromercuribenzoate is reversed by excess of dithiothreitol, which also protects the enzyme from inactivation by oxygen.

Sign in / Sign up

Export Citation Format

Share Document