1
|
Nunes NNDS, Santana LA, Sampaio MU, Lemos FJA, Oliva ML. The component of Carica papaya seed toxic to A. aegypti and the identification of tegupain, the enzyme that generates it. CHEMOSPHERE 2013; 92:413-420. [PMID: 23402920 DOI: 10.1016/j.chemosphere.2012.12.078] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Revised: 12/19/2012] [Accepted: 12/31/2012] [Indexed: 06/01/2023]
Abstract
As Aedes aegypti transmits the etiologic agents of both yellow and dengue fever; vector control is considered essential to minimise their incidence. The aim of this work was to identify the component of Carica papaya seed toxic to A. aegypti, and the identification of tegupain, the enzyme that generates it. Aqueous extracts (1%, w/v) of the seed tegument and cotyledon of C. papaya are not larvicidal isolately. However, a mixture of 17μgmL(-1) tegument extract and 27μgmL(-1) cotyledon extract caused 100% larval mortality in a bioassay. The mixture was no longer larvicidal after the tegument extract was pre-treated at 100°C for 10min. The enzyme tegupain efficiently hydrolysed the substrate Z-Phe-Arg-pNan (Km 58.8μM, Kcat 28020s(-1), Kcat/Km 5×10(8)M(-1) s(-1)), and its activity increased with 2mM dithiothreitol (DTT), at 37°C, pH 5.0. The chelating agent EDTA did not modify the enzyme activity. Inhibition of tegupain by cystatin (Kiapp 2.43nM), E64 (3.64nM, 83% inhibition), and the propeptide N-terminal sequence indicate that the toxic activity is due to a novel cysteine proteinase-like enzyme, rendered active upon the hydrolysis of a cotyledon component of C. papaya seeds.
Collapse
Affiliation(s)
- Natalia N dos S Nunes
- Departamento de Bioquímica, Universidade Federal de São Paulo, 04044-020, São Paulo, SP, Brazil
| | | | | | | | | |
Collapse
|
2
|
Native and Biotechnologically Engineered Plant Proteases with Industrial Applications. FOOD BIOPROCESS TECH 2010. [DOI: 10.1007/s11947-010-0431-4] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
|
3
|
Affiliation(s)
- Dave R van Staveren
- Institut für Pharmazie und Molekulare Biotechnologie, Universität Heidelberg, Im Neuenheimer Feld 364, D-69120 Heidelberg, Germany
| | | |
Collapse
|
4
|
Golan R, Zehavi U, Naim M, Patchornik A, Smirnoff P, Herchman M. Inhibition of Papaya latex papain by photosensitive inhibitors. 1-(4,5-dimethoxy-2-nitrophenyl)-2-nitroethene and 1,1-dicyano-2-(4,5-dimethoxy-2-nitrophenyl)-ethene. JOURNAL OF PROTEIN CHEMISTRY 2000; 19:117-22. [PMID: 10945435 DOI: 10.1023/a:1007030532433] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
1-(4,5-Dimethoxy-2-nitrophenyl)-2-nitroethene (1) was shown to be an irreversible inhibitor of papain (EC 3.4.22.2), causing a complete inhibition (120 min preincubation, pH 8.0), assuming that it attached to Cys-25 at the active site of the enzyme (while a short preincubation time caused activation). Only partial inhibition of papain was achieved, however, with 1,1-dicyano-2-(4,5-dimethoxy-2-nitrophenyl)-ethene (2), a compound synthesized in this work, which is also an irreversible inhibitor of papain. Since both compounds 1 and 2, and in each case of the inhibited enzyme, were 2-nitrobenzyl derivatives, they and the modified enzyme were expected to be photosensitive. Indeed, irradiation of the inhibited enzyme in the presence of mercaptoethanol resulted in a full recovery of the enzyme activity following inactivation with compound 1 (similar to our previous finding with beta-galactosidase) and up to 67% recovery following inhibition with compound 2.
Collapse
Affiliation(s)
- R Golan
- Faculty of Agricultural, Food and Environmental Quality Sciences, The Hebrew University of Jerusalem, Rehovot, Israel
| | | | | | | | | | | |
Collapse
|
5
|
Ambler RP, Daniel M. Rattlesnake cytochrome c. A re-appraisal of the reported amino acid sequence. Biochem J 1991; 274 ( Pt 3):825-31. [PMID: 1849408 PMCID: PMC1149985 DOI: 10.1042/bj2740825] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The amino acid sequence of rattlesnake cytochrome c was originally reported in 1965, and was one of the earlier sequences to be studied. When compared with other mitochondrial cytochromes c, the snake sequence was soon seen to be anomalous. There were several positions in which the snake protein resembled human cytochrome c, although comparable anomalies were not reported for the protein from other reptiles such as lizard and turtle. Explanations of these results have included accelerated evolution in the snake lineage, paralogy rather than orthology, and faulty determination of the sequence, and the rattlesnake is now often omitted from cytochrome c phylogenetic trees. We have re-investigated the sequence of the snake protein, and believe that the correct sequence differs in nine places from that used for evolutionary theorizing since 1965. Four of these differences are near the haem-attachment site, in a region that was only analysed for amino acid composition in the original investigation. The other five differences are towards the C-terminus of the molecule, and can be explained as being due to the wrong ordering of amino acids within peptides that had been satisfactorily purified. Despite these corrections, the rattlesnake cytochrome c sequence still more closely resembles human cytochrome c than it does that of any other protein we know. We believe that this is an example of convergent evolution, although it does appear that there has been accelerated change in the line connecting the rattlesnake to the ancestral vertebrate line. Detailed evidence for the amino acid sequence of the protein has been deposited as Supplementary Publication SUP 50162 (16 pages) at the British Library Document Supply Centre, Boston Spa. Wetherby, West Yorkshire LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1991) 273, 5.
Collapse
Affiliation(s)
- R P Ambler
- Department of Molecular Biology, University of Edinburgh, Scotland, U.K
| | | |
Collapse
|
6
|
Kooistra C, Sluyterman LA. Isosteric and non-isosteric modification of carboxyl groups of papain. BIOCHIMICA ET BIOPHYSICA ACTA 1989; 997:115-20. [PMID: 2502185 DOI: 10.1016/0167-4838(89)90142-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Guanidinated mercuri-papain (Gu-papain) was reacted with N-ethylbenzisoxazolium tetrafluoroborate at pH 4.2, 0 degree C, to yield highly reactive N-ethylsalicylamide esters. On varying the amount of reagent applied 2.5-10 carboxyl groups were modified. Appropriate plotting of the data indicated that all 12 groups exposed in the X-ray structure were modified to an extent of 80% in the final preparation, concomitant with a similar loss of activity towards N alpha-benzoyl-L-arginine ethyl ester. The preparations regained complete activity on saponification of the ester groups and removal of some oligomeric material by gel filtration. Considerable activity was recovered when the ester groups were completely replaced by amide groups by subjecting the esters to ammonolysis in 2 M ammonium acetate/ammonia (pH 9.2). The final preparation, after gel filtration, exhibited Km = 57 +/- 1 mM and kcat = 26 +/- 0.2 s-1 towards BAEE (native papain Km = 18 mM and kcat = 26 s-1). It may be concluded that replacement of a bulky modifying group by an isosteric one may cause considerable recovery of activity, emphasizing the importance of isostericity in suppressing the ionizing ability of ionizable groups; furthermore, that a large shift in overall charge, caused by amidation of all accessible carboxyl groups, does not affect the catalytic steps. The absence of effect of side-chain charges on the ion pair in the active site is briefly discussed.
Collapse
Affiliation(s)
- C Kooistra
- Department of Organic Chemistry, Eindhoven University of Technology, The Netherlands
| | | |
Collapse
|
7
|
Abstract
A cDNA clone for a thiol endoproteinase has been isolated from a bovine heart cDNA library by using a mixture of 32 synthetic oligonucleotides as a hybridization probe. The inserted region is 672 base pairs in length. It contains a sequence encoding the C-terminal region of a protein that is homologous to rat liver cathepsins B and H and to plant thiol proteinases. In addition, it contains the sequence of 442 bases corresponding to the 3' untranslated region of the mRNA. The inserted region was used as a specific probe in RNA transfer analysis; the size of the mRNA encoding the thiol endoproteinase is estimated to be approx. 1.7 kilobases. Thus, the maximum size of the encoded protein is about 350-400 amino acids.
Collapse
|
8
|
Takio K, Towatari T, Katunuma N, Teller DC, Titani K. Homology of amino acid sequences of rat liver cathepsins B and H with that of papain. Proc Natl Acad Sci U S A 1983; 80:3666-70. [PMID: 6574504 PMCID: PMC394111 DOI: 10.1073/pnas.80.12.3666] [Citation(s) in RCA: 187] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The amino acid sequences of rat liver lysosomal thiol endopeptidases, cathepsins B and H, are presented and compared with that of the plant thiol protease papain. The 252-residue sequence of cathepsin B and the 220-residue sequence of cathepsin H were determined largely by automated Edman degradation of their intact polypeptide chains and of the two chains of each enzyme generated by limited proteolysis. Subfragments of the chains were produced by enzymatic digestion and by chemical cleavage of methionyl and tryptophanyl bonds. Comparison of the amino acid sequences of cathepsins B and H with each other and with that of papain demonstrates a striking homology among their primary structures. Sequence identity is extremely high in regions which, according to the three-dimensional structure of papain, constitute the catalytic site. The results not only reveal the first structural features of mammalian thiol endopeptidases but also provide insight into the evolutionary relationships among plant and mammalian thiol proteases.
Collapse
|
9
|
Brocklehurst K, Malthouse JP. Evidence for a two-state transition in papain that may have no close analogue in ficin. Differences in the disposition of cationic sites and hydrophobic binding areas in the active centres of papain and ficin. Biochem J 1980; 191:707-18. [PMID: 7025834 PMCID: PMC1162271 DOI: 10.1042/bj1910707] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The kinetics of the reactions of the active-centre thiol groups of papain (EC 3.4.22.2) and ficin (EC 3.4.22.3) with the two-protonic-state reactivity probes 2,2'-dipyridyl disulphide, n-propyl 2-pyridyl disulphide and 4-(N-aminoethyl 2'-pyridyl disulphide)- 7-nitrobenzo-2-oxa-1,3-diazole (compound I) were studied over a wide range of pH. Differences between the reactivities of ficin and papain towards the cationic forms of the alkyl 2-pyridyl disulphide probes suggest that ficin contains a cationic site without exact analogue in papain, and the striking difference in the shapes of the pH-rate profiles for the reactions of the two enzymes with compound (1) suggests differences in the mobilities or dispositions of the active-centre histidine imidazole groups with respect to relevant hydrophobic binding areas. The evidence from reactivity-probe studies that the papain catalytic mechanism involves substantial repositioning of the active-centre imidazole group during the catalytic act does not apply also to ficin. If ficin contains an aspartic acid residue analogous to aspartic acid-158 in papain, the pKa of its carboxy group is probably significantly lower than the pKa of the analogous group in papain.
Collapse
|
10
|
Carne A, Moore CH. The amino acid sequence of the tryptic peptides from actinidin, a proteolytic enzyme from the fruit of Actinidia chinensis. Biochem J 1978; 173:73-83. [PMID: 687380 PMCID: PMC1185751 DOI: 10.1042/bj1730073] [Citation(s) in RCA: 116] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The amino acid sequences of the tryptic peptides of the thiol proteinase actinidin from Actinidia chinensis were determined by the manual dansyl--Edman procedure. There are 12 tryptic peptides, which give a polypeptide chain of 220 residues with a mol.wt. of 23500. An alignment of the tryptic peptides was made by using the X-ray-crystallographic data of Baker [(1977) J. Mol. Biol. 115, 263--277] determined at 0.28 nm resolution on crystalline actinidin. Detailed evidence for the amino acid sequences of the tryptic peptides has been deposited as Supplementary Publication SUP 50083 (14 pages) at the British Library Lending Division, Boston Spa, Wetherby, West Yorkshire LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1978) 169, 5.
Collapse
|
11
|
Shipton M, Stuchbury T, Brocklehurst K. 4-Chloro-7-nitrobenzo-2-oxa-1,3-diazole as a reactivity probe for the investigation of the thiol proteinases. evidence that ficin and bromelain may lack carboxyl groups conformationally equivalent to that of aspartic acid-158 of papain. Biochem J 1976; 159:235-44. [PMID: 11778 PMCID: PMC1164110 DOI: 10.1042/bj1590235] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
1. 4-Chloro-7-nitrobenzo-2-oxa-1,3-diazole (Nbd chloride) was used as a reactivity probe to characterize the active centres of papin (EC 3.4.22.2), ficin (EC 3.4.22.3) and bromelain (EC 3.4.22.4). 2. In the pH range 0-8 Nbd chloride probably exists mainly as a monocation, possibly with the proton located on N-1 of the oxadiazole ring. 3. Spectroscopic evidence is presented for the intermediacy of Meisenheimer-type adducts in the reaction of Nbd chloride with nucleophiles. 4. The pH-dependence of the second-order rate constants (k) of the reactions of the three enzymes with Nbd chloride was determined at 25 degrees C, I = 0.1 mol/litre in 6.7% (v/v) ethanol in the pH range 2.5-5, where, at least for papain and ficin, the reactions occur specifically with their active-centre thiol groups. The pH-k profile for the papain reaction is bell-shaped (pKaI = 3.24, pKaII = 3.44 and k = 86M(-1)-s(-1), whereas that for ficin is sigmoidal (pKa = 3.6, k = 0.36M(-1)-s(-1), the rate increasing with increasing pH. The profile for the bromelain reaction appears to resemble that for the ficin reaction, but is complicated by amino-group labelling. 5. The bell-shaped profile of the papain reaction is considered to arise from the reaction of the thiolate ion of cysteine-25, maintained in acidic media by interaction with the side chain of histidine-159, with the Nbd chloride monocation hydrogen-bonded at its nitro group to the un-ionized form of the carboxyl group of aspartic acid-158. The lack of acid catalysis in the corresponding reactions of ficin and probably of bromelain suggests that these enzymes may lack carboxyl groups conformationally equivalent to that of aspartic acid-158 of papain. The possible consequences of this for the catalytic sites of these enzymes is discussed.
Collapse
|
12
|
|
13
|
Lowe G, Whitworth AS. A kinetic and fluorimetric investigation of papain modified at tryptophan-69 and -177 by N-bromosuccinimide. Biochem J 1974; 141:503-15. [PMID: 4455219 PMCID: PMC1168105 DOI: 10.1042/bj1410503] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
A systematic study of the modification of papain (its thiol group protected as a disulphide with mercaptoethanol) by N-bromosuccinimide, showed that 2 molar equiv. modified tryptophan-69 and 4 molar equiv. modified tryptophan-69 and -177. The Michaelis parameters for the catalysed hydrolysis of N-benzyloxycarbonylglycine p-nitrophenyl ester by these modified enzymes were determined. The enzymic activity of the modified enzymes was not seriously impaired, but modification of tryptophan-177 raised the apparent pK(a) of the acidic limb of the pH profile by more than 1 pH unit for both k(cat.) and k(cat.)/K(m). The fluorescence spectra (excitation at 288nm) of the modified enzymes showed that tryptophan-69 contributed about 8% to the fluorescence intensity, whereas tryptophan-177 contributed about 46% at neutral pH. However, the contribution of tryptophan-177 was quenched at low pH and its fluorescence intensity showed sigmoidal pH-dependence, with an apparent pK(a) of 4.2. Histidine-159, which is in close contact with tryptophan-177, is considered to be the residue responsible for the fluorescence quenching. When tryptophan-177 was modified, presumably generating a less hydrophobic micro-environment, the apparent pK(a) determined kinetically was raised to about 5.4. By comparing the Michaelis parameters of native papain, papain modified at tryptophan-69 and papain modified at tryptophan-69 and -177 with N-benzyloxycarbonylglycylglycine amide and N-benzyloxycarbonylglycyltryptophan amide, tryptophan-69 and tryptophan-177 were shown to be structural features of the S(2) and S(1)' subsites respectively.
Collapse
|
14
|
Kirschenbaum DM. The enhancement of the enzymatic activity of papain by reaction with N-bromosuccinimide. BIOCHIMICA ET BIOPHYSICA ACTA 1971; 235:159-63. [PMID: 5317795 DOI: 10.1016/0005-2744(71)90043-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
|
15
|
Drenth J, Jansonius JN, Koekoek R, Wolthers BG. The structure of papain. ADVANCES IN PROTEIN CHEMISTRY 1971; 25:79-115. [PMID: 4946704 DOI: 10.1016/s0065-3233(08)60279-x] [Citation(s) in RCA: 177] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
|
16
|
Brocklehurst K, Little G. A novel reactivity of papain and a convenient active site titration in the presence of other thiols. FEBS Lett 1970; 9:113-116. [PMID: 11947645 DOI: 10.1016/0014-5793(70)80327-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- K Brocklehurst
- Department of Biochemistry and Chemistry, Medical College of St. Bartholomew's Hospital, Charterhouse Square, E.C.1, London, England
| | | |
Collapse
|