Disease relevance of Carica

• Nucleotide sequence of the capsid protein gene and 3' non-coding region of papaya mosaic virus RNA [1].
• Inhibition of cysteine proteinases by Carica papaya cystatin produced in Escherichia coli [2].
• A model of the 3-D structure of a major house dust mite allergen Der p I associated with hypersensitivity reactions in humans was built from its amino acid sequence and its homology to three known structures, papain, actinidin and papaya proteinase omega of the cysteine proteinase family [3].
• In the 18-19 d pregnant rat uterus, the contractile effect of crude papaya latex was characterized by tetanic spasms [4].
• The effect of a decoction of fig leaves (Ficus carica), as a supplement to breakfast, on diabetes control was studied in insulin-dependent diabetes mellitus (IDDM) patients (six men, four women, age 22-38 years, body mass index (BMI): 20.8 +/- 3.0 kg/m2, HbA1c 7.6 +/- 0.9% with a mean duration of diabetes of 9 +/- 6.3 years) [5].

High impact information on Carica

• Overproduction of citrate was shown to result in aluminum tolerance in transgenic tobacco (Nicotiana tabacum) and papaya (Carica papaya) plants [6].
• The crystal structure of the QC from the latex of Carica papaya (PQC) has been determined at 1.7A resolution [7].
• We found that papain, a cysteine protease in latex of the Papaya tree (Carica papaya, Caricaceae), is a crucial factor in the defense of the papaya tree against lepidopteran larvae such as oligophagous Samia ricini (Saturniidae) and two notorious polyphagous pests, Mamestra brassicae (Noctuidae) and Spodoptera litura (Noctuidae) [8].
• Two of these clones, p48h-107 and p48h-17, show high homology to adenylate kinase and papaya proteinase I, respectively [9].
• Preincubation of extracts with 4 mM phenylmethylsulfonyl fluoride, a serine proteinase inhibitor, or with 25 microM L-trans-epoxysuccinyl-L-leucylamido(4-guanidino) butane, a cysteine proteinase inhibitor, allowed the identification of enzymes from both classes in extracts of tomato fruit and papaya latex [10].

Chemical compound and disease context of Carica

• The published DNA sequence that includes the gene for the envelope glycoprotein gp67 of the baculovirus Autographa californica nuclear polyhedrosis virus also contains a segment that shows 32% amino acid identity to papain, a cysteine endopeptidase from the papaya plant (Carica papaya) [11].
• Contraceptive efficacy, reversibility and toxicity, if any, of the benzene, chloroform and ethyl acetate chromatographic fractions of the chloroform extract of the seeds of Carica papaya have been investigated in adult male rabbits at a dose regimen of 50 mg/animal/day for 150 days of treatment [12].
• Papain (from papaya latex; EC 3.4.22.2) and Pronase (from Streptomyces griseus; EC 3.4.24.31) caused optimum depolymerization of chitosan at pH 3.5 and 37 degrees C, resulting in LMMC (low molecular mass chitosan) and chito-oligomeric-monomeric mixture [13].

Biological context of Carica

• For the papaya peptidase A-catalysed hydrolysis of N-benzyloxycarbonylglycine p-nitrophenyl ester at pH 5.5 kcat. was found to be 16.7s-1, which is about 3 times the value found for the same reaction catalysed by papain [14].
• It has considerable structural similarity with papain and papaya proteinase omega, including conservation of the catalytic site and of the disulphide bonding [15].
• Crystal structure of glycyl endopeptidase from Carica papaya: a cysteine endopeptidase of unusual substrate specificity [16].
• Two cDNA clones for plant cysteine proteinases have been isolated from a Carica papaya (paw-paw, papaya) leaf tissue cDNA library by using a mixture of 16 synthetic oligodeoxyribonucleotides as a hybridization probe [17].
• Structure-function relationships in the cysteine proteinases actinidin, papain and papaya proteinase omega. Three-dimensional structure of papaya proteinase omega deduced by knowledge-based modelling and active-centre characteristics determined by two-hydronic-state reactivity probe kinetics and kinetics of catalysis [18].

Anatomical context of Carica

• Semen quality in papaya workers with long term exposure to ethylene dibromide [19].
• The modes of action of C. papaya latex and of D(+)-glucosamine in cell wall breakdown are discussed [20].

Associations of Carica with chemical compounds

• Papain is a sulfhydryl protease from the latex of the papaya fruit [21].
• Latexes of both papaya and the wild fig were rich in cysteine-protease activity [8].
• 3. The active centre of papaya peptidase A was investigated by using 2,2'-dipyridyl disulphide and 4-chloro-7-nitrobenzofurazan as reactivity probes [22].
• The most marked difference in the Cys/His system is that the pKa for the loss of the ion-pair state to form -S-/-Im is 8.1-8.3 for papaya proteinase omega, whereas it is 9.5 for both actinidin and papain [18].
• Values of k+2/Ks and k+3 for the reactions of papain, actinidin and papaya peptidase II with N-benzoylglycine and N-(beta-phenylpropionyl)glycine methyl thionoesters were obtained by a pre-steady-state kinetic study [23].

Gene context of Carica

• CD spectral analysis indicated a high alpha-helical content, which contrasts with plant QC from Carica papaya [24].
• Phylogenetic trees based on the multiple sequence alignments of three conserved domains in ORF1 product and capsid protein reveal a close relationship of P1AMV to papaya mosaic virus and clover yellow mosaic virus [25].
• Chromatographic separation of ficin from Ficus carica yielded six proteolytic fractions with a different specificity towards FX [26].
• After four weeks of papaya consumption, results showed significant increase (p<0.01) in serum total antioxidant status and glutathione reductase level but showed no significant increase (p>0.05) in blood glutathione peroxidase level [27].
• Papaya proteinase omega is similar to actinidin in that it lacks the second catalytically influential group with pKa approx. 4 present in papain and possesses a catalytically influential group with pKa 5.5-6 [18].

Analytical, diagnostic and therapeutic context of Carica

• Molecular cloning of two cysteine proteinases from paw-paw (Carica papaya) [17].
• Chymopapain, a cysteine protease of papaya latex, has been purified with the use of fast protein liquid chromatography [28].
• The four known proteinases from papaya latex, namely papain (EC 3.4.22.2), chymopapain (EC 3.4.22.6), caricain (EC 3.4.22.30), and glycyl endopeptidase (EC 3.4.22.25), were purified to homogeneity and fully characterized by single radial immunodiffusion and active-site titration [29].
• Thermal denaturation of four Carica papaya cysteine proteinases (papain, chymopapain, papaya proteinases 3 and 4) was studied as a function of pH using high-sensitivity differential scanning calorimetry [30].
• One hundred and eleven samples of processed fruit juices (apple, grape, pineapple, papaya, guava, banana and mango) and 38 samples of sound fruits (apple, papaya, mango, pear and peach) produced and marketed in Brazil, were analysed for patulin by HPLC [31].

References