scholarly journals The amino acid sequence around the active-site cysteine and histidine residues of stem bromelain

1970 ◽  
Vol 117 (2) ◽  
pp. 341-346 ◽  
Author(s):  
S. S. Husain ◽  
G. Lowe

Stem bromelain that had been irreversibly inhibited with 1,3-dibromo[2-14C]-acetone was reduced with sodium borohydride and carboxymethylated with iodoacetic acid. After digestion with trypsin and α-chymotrypsin three radioactive peptides were isolated chromatographically. The amino acid sequences around the cross-linked cysteine and histidine residues were determined and showed a high degree of homology with those around the active-site cysteine and histidine residues of papain and ficin.

1970 ◽  
Vol 117 (2) ◽  
pp. 333-340 ◽  
Author(s):  
S. S. Husain ◽  
G. Lowe

Ficin that had been prepared from the latex of Ficus glabrata by salt fractionation and chromatography on carboxymethylcellulose was completely and irreversibly inhibited with 1,3-dibromo[2-14C]acetone and then treated with N-(4-dimethylamino-3,5-dinitrophenyl)maleimide in 6m-guanidinium chloride. After reduction and carboxymethylation of the labelled protein, it was digested with trypsin and α-chymotrypsin. Two radioactive peptides and two coloured peptides were isolated chromatographically and their sequences determined. The radioactive peptides revealed the amino acid sequences around the active-site cysteine and histidine residues and showed a high degree of homology with the omino acid sequence around the active-site cysteine and histidine residues in papain. The coloured peptides allowed the amino acid sequence around the buried cysteine residue in ficin to be determined.


1968 ◽  
Vol 108 (5) ◽  
pp. 861-866 ◽  
Author(s):  
S. S. Husain ◽  
G. Lowe

Papain that had been irreversibly inhibited with 1,3-dibromo[2−14C]acetone was reduced with sodium borohydride and carboxymethylated with iodoacetic acid. After digestion with trypsin and α-chymotrypsin the radioactive peptides were purified chromatographically. Their amino acid composition indicated that cysteine-25 and histidine-106 were cross-linked. Since cysteine-25 is known to be the active-site cysteine residue, histidine-106 must be the active-site histidine residue.


2000 ◽  
Vol 182 (8) ◽  
pp. 2277-2284 ◽  
Author(s):  
W. Keith Ray ◽  
Gang Zeng ◽  
M. Benjamin Potters ◽  
Aqil M. Mansuri ◽  
Timothy J. Larson

ABSTRACT Rhodaneses catalyze the transfer of the sulfane sulfur from thiosulfate or thiosulfonates to thiophilic acceptors such as cyanide and dithiols. In this work, we define for the first time the gene, and hence the amino acid sequence, of a 12-kDa rhodanese fromEscherichia coli. Well-characterized rhodaneses are comprised of two structurally similar ca. 15-kDa domains. Hence, it is thought that duplication of an ancestral rhodanese gene gave rise to the genes that encode the two-domain rhodaneses. The glpEgene, a member of the sn-glycerol 3-phosphate (glp) regulon of E. coli, encodes the 12-kDa rhodanese. As for other characterized rhodaneses, kinetic analysis revealed that catalysis by purified GlpE occurs by way of an enzyme-sulfur intermediate utilizing a double-displacement mechanism requiring an active-site cysteine. TheKm s for SSO3 2− and CN− were 78 and 17 mM, respectively. The apparent molecular mass of GlpE under nondenaturing conditions was 22.5 kDa, indicating that GlpE functions as a dimer. GlpE exhibited ak cat of 230 s−1. Thioredoxin 1 from E. coli, a small multifunctional dithiol protein, served as a sulfur acceptor substrate for GlpE with an apparentKm of 34 μM when thiosulfate was near itsKm , suggesting that thioredoxin 1 or related dithiol proteins could be physiological substrates for sulfurtransferases. The overall degree of amino acid sequence identity between GlpE and the active-site domain of mammalian rhodaneses is limited (∼17%). This work is significant because it begins to reveal the variation in amino acid sequences present in the sulfurtransferases. GlpE is the first among the 41 proteins in COG0607 (rhodanese-related sulfurtransferases) of the database Clusters of Orthologous Groups of proteins (http://www.ncbi.nlm.nih.gov/COG/ ) for which sulfurtransferase activity has been confirmed.


1989 ◽  
Vol 44 (7) ◽  
pp. 817-824 ◽  
Author(s):  
Aftab Ahmed ◽  
Meeno Jahan ◽  
Gerhard Braunitzer ◽  
Helmut Pechlaner

The complete amino acid sequences of the hemoglobins from the adult European polecat (Mustela putorius) are presented. The erythrocytes contain two hemoglobin components and three globin chains (α I, α II and β). The primary structure of globin chains and of the tryptic peptides determined in liquid- and gas-phase sequantors. Comparing the sequences of the globin chains of the polecat with that of human Hb-A, 17 (23.9%) substitutions were recognized in the α I, 16 (22.5%) in the α II and 14 (20.4%) in the β chain. A high degree of homology observed with other representatives of the family Mustelidae.


1997 ◽  
Vol 327 (1) ◽  
pp. 199-202 ◽  
Author(s):  
Karen L. LEE ◽  
Karen L. ALBEE ◽  
Richard J. BERNASCONI ◽  
Tim EDMUNDS

The amino acid sequences of ananain (EC 3.4.22.31) and stem bromelain (3.4.22.32), two cysteine proteases from pineapple stem, are similar yet ananain and stem bromelain possess distinct specificities towards synthetic peptide substrates and different reactivities towards the cysteine protease inhibitors E-64 and chicken egg white cystatin. We present here the complete amino acid sequence of ananain and compare it with the reported sequences of pineapple stem bromelain, papain and chymopapain from papaya and actinidin from kiwifruit. Ananain is comprised of 216 residues with a theoretical mass of 23464 Da. This primary structure includes a sequence insert between residues 170 and 174 not present in stem bromelain or papain and a hydrophobic series of amino acids adjacent to His-157. It is possible that these sequence differences contribute to the different substrate and inhibitor specificities exhibited by ananain and stem bromelain.


1971 ◽  
Vol 123 (4) ◽  
pp. 591-600 ◽  
Author(s):  
John Bridgen

Four unique carboxymethylcysteine-containing peptides were isolated from tryptic and chymotryptic digests of trout muscle actin carboxymethylated with iodo[2-14C]acetic acid in 6m-guanidinium chloride. The amino acid sequences of these peptides were determined and showed a high degree of homology with the corresponding sequences from rabbit actin. One of the radioactive peptides was the C-terminal peptide and another sequence probably contained the cysteine residue from the N-terminal region of the protein.


1974 ◽  
Vol 137 (3) ◽  
pp. 505-512 ◽  
Author(s):  
Joseph P. Brown ◽  
Richard N. Perham

1. The two cysteine residues forming the disulphide bridge that comprises part of the active site of lipoamide dehydrogenase from pig heart were specifically labelled with iodo[2-14C]acetic acid. 2. A tryptic peptide containing these carboxymethylcysteine residues was isolated from digests of reduced and S-carboxymethylated lipoamide dehydrogenase and its amino acid sequence of 23 residues was determined. 3. The sequence is highly homologous with a similar sequence containing the active-site disulphide bridge of lipoamide dehydrogenase derived from the 2-oxoglutarate dehydrogenase complex of Escherichia coli (Crookes strain) and it is probable that, as in the bacterial enzyme, the disulphide bridge forms an intrachain loop containing six residues. The results indicate that the bacterial and mammalian proteins have a common genetic origin. 4. Amino acid sequences containing six other unique carboxymethylcysteine residues were also partly determined. 5. The analysis of the primary structure thus far is consistent with the view that the enzyme (mol.wt. approx. 110000) is composed of two identical polypeptide chains.


Sign in / Sign up

Export Citation Format

Share Document