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1.
Aspartate transcarbamylase (EC 2.1.3.2) was purified to homogeniety from germinated mung bean seedlings by treatment with
carbamyl phosphate. The purified enzyme was a hexamer with a subunit molecular weight of 20,600. The enzyme exhibited multiple
activity bands on Polyacrylamide gel electrophoresis, which could be altered by treatment with carbamyl phosphate or UMP indicating
that the enzyme was probably undergoing reversible association or dissociation in the presence of these effectors. The carbamyl
phosphate stabilized enzyme did not exhibit positive homotropic interactions with carbamyl phosphate and hysteresis. The enzyme
which had not been exposed to carbamyl phosphate showed a decrease in specific activity with a change in the concentration
of both carbamyl phosphate and protein. The carbamyl phosphate saturation and UMP inhibition patterns were complex with a
maximum and a plateau region. The partially purified enzyme also exhibited hysteresis and the hysteretic response, a function
of protein concentration, was abolished by preincubation with carbamyl phosphate and enhanced by preincubation with UMP. All
these observations are compatible with a postulation that the enzyme activity may be regulated by slow reversible association-dissociation
dependent on the interaction with allosteric ligands 相似文献
2.
We report a method for the purification of vicilin from mung bean (Vigna radiata) mainly on the basis of solubility of mung bean vicilin even in high salt. Mung bean vicilin remains in solution even after 90% relative saturation of ammonium sulphate. The resulting supernatant after dialysis was subjected to gel filtration (Sephadex G-150) to remove other contaminant polypeptides, and finally the protein was purified by DEAE cellulose chromatography. This purified fraction exhibited 3 bands on SDS-PAGE compared with vicilin from other legumes which exhibite more than 3 bands generally. The results raise the possibility that the presence of the two small polypeptides in vicilin preparations is the breakdown product of the major larger one of mol.wt. 52 K and that vicilin may be a tetramer of four subunits of Mr 52000. That the high salt-soluble protein containing 52 K subunit is vicilin has been determined by several criteria. 相似文献
3.
Effects of anti-microbule drugs on tubulin polymerizationin vitro were investigated using purified mung bean (Vigna radiata) tubuli. Colchicine induced the formation of macrotubules at the relatively low concentration of 10 μM. and the appearance
of corkscrew-like filaments from the ends of the macrotubules at concentrations of more than 100 μM. Vinblastine substantially
inhibited polymerization at 1 μM and caused the formation of paracrystals at concentrations greater than 10 μM. Oryzalin inhibited
polymerization at 1 μM partially and at 10 μM completely. Paracrystal formation was also induced by cremart at 10 μM, but
these paracrystals appeared to be more rigid than those induced by vinblastine. Amiprophos methyl (APM), with a chemical configuration
similar to cremart, substantially inhibited polymerization at 1 μM, but the formation of paracrystals was weak. Griseofulvin
at 10 μMalso inhibited the polymerization of tubulin while at higher concentrations aggregates of helices were formed. Inhibition
of polymerization by phenylcarbamate herbicides was more effective than that caused by benzimidazoylcarbamate fungicides.
The effects of drugs onin vitro preformed (MTs) were also investigated. Colchicine and vinblastine showed identical effects to those on the polymerization
process. Griseofulvin, cremart and APM induced only macrotubule formation while the other drugs tested had no major effects 相似文献
4.
Characterization and developmental expression of single-stranded telomeric DNA-binding proteins from mung bean (Vigna radiata) 总被引:2,自引:0,他引:2
We have identified and characterized protein factors from mung bean (Vigna radiata) nuclear extracts that specifically bind the single-stranded G-rich telomeric DNA repeats. Nuclear extracts were prepared from three different types of plant tissue, radicle, hypocotyl, and root, in order to examine changes in the expression patterns of telomere-binding proteins during the development of mung bean. At least three types of specific complexes (A, B, and C) were detected by gel retardation assays with synthetic telomere and nuclear extract from radicle tissue, whereas the two major faster-migrating complexes (A and B) were formed with nuclear extracts from hypocotyl and root tissues. Gel retardation assays also revealed differences in relative amount of each complex forming activity in radicle, hypocotyl, and root nuclear extracts. These data suggest that the expression of telomere-binding proteins is developmentally regulated in plants, and that the factor involved in the formation of complex C may be required during the early stages of development. The binding factors have properties of proteins and are hence designated as mung bean G-rich telomere-binding proteins (MGBP). MGBPs bind DNA substrates with three or more single-stranded TTTAGGG repeats, while none of them show binding affinity to either double-stranded or single-stranded C-rich telomeric DNA. These proteins have a lower affinity to human telomeric sequences than to plant telomeric sequences and do not exhibit a significant binding activity to Tetrahymena telomeric sequence or mutated plant telomeric sequences, indicating that their binding activities are specific to plant telomere. Furthermore, RNase treatment of the nuclear extracts did not affect the complex formation activities. This result indicates that the single-stranded telomere-binding activities may be attributed to a simple protein but not a ribonucleoprotein. The ability of MGBPs to bind specifically the single-stranded TTTAGGG repeats may suggest their in vivo functions in the chromosome ends of plants. 相似文献
5.
JAE‐GYUN GWAG JONG‐WOOK CHUNG HUN‐KI CHUNG JEONG‐HEUI LEE KYUNG‐HO MA ANUPAM DIXIT YONG‐JIN PARK EUN‐GI CHO TAE‐SAN KIM SUK‐HA LEE 《Molecular ecology resources》2006,6(4):1132-1134
The present work reports the isolation and characterization of new polymorphic microsatellites in mung bean (Vigna radiata L.). Of 93 designed primer pairs, seven were found to amplify polymorphic microsatellite loci, which were then characterized using 34 mung bean accessions. The number of alleles ranged from two to five alleles per locus with an average of three alleles. Observed and expected heterozygosity values ranged from 0 to 0.088 and from 0.275 to 0.683, respectively. All seven loci showed significant deviations from Hardy–Weinberg equilibrium, whereas only one pairwise combination (GBssr‐MB77 and GBssr‐MB91) exhibited significant departure from linkage disequilibrium. These newly developed markers are currently being utilized for diversity assessment within the mung bean germplasm collection of the Korean Gene Bank. 相似文献
6.
A chitinase with antifungal activity was isolated from mung bean (Phaseolus mungo) seeds. The procedure entailed aqueous extraction, (NH4)2SO4 precipitation, ion-exchange chromatography on CM-Sepharose, high-performance liquid chromatography (HPLC) on Poros HS-20, and gel filtration on Sephadex G-75. The protein exhibited a molecular mass of 30.8 kDa in SDS–polyacrylamide gel electrophoresis. Its pI was 6.3 as determined by isoelectric focusing. The specific activity of the chitinase was estimated to be 3.81 U/mg. The enzyme expressed its optimum activity at pH 5.4 and was stable from 40 to 50 °C. It exerted antifungal action toward Fusarium solani, Fusarium oxysporum, Mycosphaerella arachidicola, Pythium aphanidermatum, and Sclerotium rolfsii. 相似文献
7.
Glutamine synthetase (L-glutamate : ammonia ligase, EC 6.3.1.2) fromPhaseolus aureus (mung bean) seedlings was purified to homogeneity by ammonium sulphate fractionation, DEAE-cellulose chromatography, Sephadex
G-200 gel filtration and affinity chromatography on histidine-Sepharose. The enzyme had a molecular weight of 775,000 ± 25,000.
The enzyme consisted of identical subunits with an approximate subunit molecular weight of 50,000. Hyperbolic saturation curves
were obtained with the substrates, glutamate, ATP and hydroxylamine.
Antibody, raised in the rabbit, against mung bean glutamine synthetase, completely inhibited the activity of the enzyme. Preincubation
of the enzyme with glutamate and ATP, prior to the addition of the antibody, partially protected the enzyme against inhibition.
TheK
m values of this enzyme-antibody complex and the native enzyme were identical (glutamate, 2.5mM; ATP, 1 mM; hydroxylamine,
0.5 mM). The Km values of the partially inhibited enzyme (the enzyme pretreated with antibody prior to the addition of substrates)
were 2-fold higher than those of the native enzyme. These results suggested that the substrate-induced conformational changes
in the enzyme were responsible for the protection against inhibition of the enzyme activity by the antibody. 相似文献
8.
A novel protease inhibitor, designated mungoin, with both antifungal and antibacterial activities, and exhibiting a molecular mass of 10 kDa in SDS-polyacrylamide gel electrophoresis, was isolated from mung bean (Phaseolus mungo) seeds. The isolation procedure involved a combination of extraction, ammonium sulfate precipitation, ion exchange chromatography on CM-Sephadex, and high-performance liquid chromatography (HPLC) on SP-Toyopearl. Its isoelectric point was estimated to be 9.8 by isoelectric focusing. Its N-terminal amino acid sequence was determined to be EMPGKPACLDTDDFCYKP, demonstrating some resemblance to the C-terminal sequences of other protease inhibitors and inhibitor precursors from leguminous plants. It exerted a potent inhibitory action toward a variety of fungal species including Physalospora piricola, Mycosphaerella arachidicola, Botrytis cinerea, Pythium aphanidermatum, Sclerotium rolfsii and Fusarium oxysporum, as well as an antibacterial action against Staphylococcus aureus. In addition, this novel plant protease inhibitor displayed anti-proliferative activity toward tumor cells. 相似文献
9.
M Pal U Ghosh M Chandra A Pal B B Biswas 《Indian journal of biochemistry & biophysics》1991,28(5-6):449-455
The procedure relied on a protocol in which shoot organogenesis was induced on cotyledons of mung bean genotypes selected for susceptibility to agrobacterium seems to work reproducibly if not efficiently. Approximately 4-5% of the shoots produced on the kanamycin selected cotyledons are transgenic based on assays on kanamycin resistance and GUS activity. This demonstrated that transformation and regeneration in mung bean are possible. However, raising the transformed plants in field condition is yet to be perfected. 相似文献
10.
Purification and partial characterization of an aminopeptidase from mung bean cotyledons 总被引:1,自引:0,他引:1
An aminopeptidase (EC 3.4.11.-) was purified to homogeneity, as judged by SDS-PAGE. from mung bean ( Vigna radiata ) cotyledons. The molecular mass of this peptidase was estimated as 75 kDa by gel filtration. When an oligopeptide consisting of 5 amino acid residues was used as substrate, amino acids were released in the order of the N-terminal sequence of the oligopeptide chain. This enzyme apparently requires free sulfhydryl for its activity, as judged by the effects of various proteinase inhibitors. Among aminoacyl- p -nitroanilides examined for the availability as substrates of the enzyme, p -nitroanilides with hydrophobic amino acids were preferred substrates. According to western immunoblot profiles, the enzyme level in cotyledons was high at the early stage of imbibition and declined rapidly after germination. 相似文献
11.
12.
Abstract. Water stress created by withholding irrigation in mung bean resulted in decreased leaf water potential and nodule moisture content. Decreased leaf water potential was associated with decreased activity of nitrogenase, glutamine synthetase (GS), asparagine synthetase (AS), aspartate amino transferase (AAT), xanthine dehydrogenase (XDH) and uricase. However, the activity of glutamate dehydrogenase increased three-fold under severe stress. The activity of allantoinase and allantoicase was not affected by moderate stress but decreased under severe stress. The in vitro production of allantoic acid from allantoin and uric acid in the cytosol fraction decreased more than its production from xanthine and hypoxanthine. The production of NADH also decreased under stress.
During recovery from severe stress, the activity of XDH and uricase further decreased, whilst that of allantoinase and allantoicase increased compared to the control. This corresponded with the higher content of ureides during recovery. The recovery in other enzymes was not complete although leaf water potential and nodule moisture content recovered fully within 24 h. 相似文献
During recovery from severe stress, the activity of XDH and uricase further decreased, whilst that of allantoinase and allantoicase increased compared to the control. This corresponded with the higher content of ureides during recovery. The recovery in other enzymes was not complete although leaf water potential and nodule moisture content recovered fully within 24 h. 相似文献
13.
Cytosolic fructose-1,6-P(2) (FBP) aldolase (ALD(c)) from germinated mung beans has been purified 1078-fold to electrophoretic homogeneity and a final specific activity of 15.1 micromol FBP cleaved/min per mg of protein. SDS-PAGE of the final preparation revealed a single protein-staining band of 40 kDa that cross-reacted strongly with rabbit anti-(carrot ALD(c))-IgG. The enzyme's native M(r) was determined by gel filtration chromatography to be 160 kDa, indicating a homotetrameric quaternary structure. This ALD is a class I ALD, since EDTA or Mg(2+) had no effect on its activity, and was relatively heat-stable losing 0-25% of its activity when incubated for 5 min at 55-65 degrees C. It demonstrated: (i) a temperature coefficient (Q(10)) of 1.7; (ii) an activation energy of 9.2 kcal/mol active site; and (iii) a broad pH-activity optima of 7.5. Mung bean ALD(c) is bifunctional for FBP and sedoheptulose-1,7-P(2) (K(m) approximately 17 microM for both substrates). ATP, ADP, AMP and ribose-5-P exerted inhibitory effects on the activity of the purified enzyme. Ribose-5-P, ADP and AMP functioned as competitive inhibitors (K(i) values=2.2, 3.1 and 7.5mM, respectively). By contrast, the addition of 2mM ATP: (i) reduced V(max) by about 2-fold, (ii) increased K(m)(FBP) by about 4-fold, and (iii) shifted the FBP saturation kinetic plot from hyperbolic to sigmoidal (h=1.0 and 2.6 in the absence and presence of 2mM ATP, respectively). Potent feedback inhibition of ALD(c) by ATP is suggested to help balance cellular ATP demands with the control of cytosolic glycolysis and respiration in germinating mung beans. 相似文献
14.
Megan E. Reardon 《Journal of Plant Interactions》2017,12(1):295-303
We studied the effects of temperature, carbon dioxide and abscisic acid on mung bean (Vigna radiata). Plants were grown under 26/22°C or 32/28°C (16?h?light/8?h?dark) at 400 or 700?μmol?mol?1 CO2 and received ABA application of 0 or 100?μl (10?μg) every other day for three weeks, after eight days of initial growth, in growth chambers. We measured 24 parameters. As individual factors, in 16 cases temperature; in 8 cases CO2; in 9 cases ABA; and as interactive factors, in 4 cases, each of temperature?×?CO2, and CO2?×?ABA; and in 2 cases, temperature?×?ABA were significant. Higher temperatures increased growth, aboveground biomass, growth indices, photochemical quenching (qP) and nitrogen balance index (NBI). Elevated CO2 increased growth and aboveground biomass. ABA decreased growth, belowground biomass, qP and flavonoids; increased shoot/root mass ratio, chlorophyll and NBI; and had little role in regulating temperature–CO2 effects.
Abbreviations: AN: net CO2 assimilation; E: transpiration; Fv/Fm: maximum quantum yield of PSII; gs: stomatal conductance; LAR: leaf area ratio; LMA: leaf mass per area; LMR: leaf mass ratio;φPSII: effective quantum yield of PSII; qNP: non-photochemical quenching; qP: photochemical quenching; SRMR: shoot to root mass ratio; WUE: water use efficiency 相似文献
15.
Paclobutrazol (PB) only slightly stimulated the rooting of mung bean cuttings but, interestingly, the number of adventitious roots formed was dramatically increased when PB was used together with indole-3-butyric acid (IBA). Application of PB in the first phase of root formation, when root initials are induced, caused the greatest enhancement of the promotive effect of IBA on rooting. Investigation of the effect of PB on uptake, transport and metabolism of [5-3 H]-IBA in mung bean cuttings revealed some changes in the rate of metabolism of IBA in comparison with control cuttings. PB was found to be involved in the partitioning of carbohydrates along the cuttings. Application of sucrose, like PB to the base of IBA-treated cuttings enhanced the effect of IBA. The patterns of the effects of PB and IBA, separately and together, on rooting were similar in defoliated and intact cuttings, however the number of roots was much lower in the defoliated cuttings, which lacked a source of assimilates. PB counteracted the effect of GA3 in the upper regions of the cuttings and seemed to increase the sink capacity at the base of the cuttings. The results of the present study clearly demonstrated the enhancing influence of PB on IBA stimulation of the rooting of mung bean cuttings. It is suggested that PB may affect the rate of metabolism of IBA during rooting and the status of the local sink, in the base of the cuttings, thus partially contributing to the enhancement of the rooting-promotive effect of IBA. 相似文献
16.
Ayyanar Manickam Els J. M. Van Damme Kandasamy Kalaiselvi Peter Verhaert Willy J. Peumans 《Physiologia plantarum》1996,97(3):524-530
Until now no 'early-methionine-labelled' (Em) proteins have been reported in the Fabaceae. To check whether a previously isolated low-molecular mass albumin from dry mung bean embryonic axes possibly corresponded to an Em-like protein, the protein was purified, sequenced and its cDNA clone isolated and characterized. N-terminal sequencing of cyanogen bromide cleavage products of the protein revealed homology with previously described Em-like proteins from other species. Analysis of cDNA clones encoding the mung bean Em protein revealed the presence of two classes of Em proteins and confirmed their homology to the previously characterized Em-like proteins. In vivo labelling and northern blot analysis further demonstrated that the mung bean protein is synthesized during early germination of the axes and that abscisic acid (ABA) extends its synthesis. It appears, therefore, that legumes also contain maturation-specific, ABA-responsive Em-like proteins. 相似文献
17.
M Vijaya N Sukanya H S Savithri N A Rao 《Indian journal of biochemistry & biophysics》1991,28(4):252-256
A naturally occurring inhibitor of serine hydroxymethyltransferase (EC 2.1.2.1) in mung bean seedlings extracts was purified by ammonium sulphate precipitation, phenyl-Sepharose chromatography followed by heating to release the inhibitor bound to the protein. The inhibitor had an absorption maximum at 200 nm, was not precipitated by trichloroacetic acid, was dialysable and resistant to inactivation by heating at 98 degrees C for 4 hr, protease and ribonuclease digestion; but was acid labile. The chromatographically pure preparation inhibited both mung bean and sheep liver SHMT. Qualitative and quantitative analyses indicated that it contained a carbohydrate moiety, an O-amino and vicinal diol groups. Paper electrophoresis at pH 4.3 suggested that the inhibitor was positively charged. 相似文献
18.
19.
Random amplified polymorphic DNA (RAPD) analysis in Indian mung bean (Vigna radiata (L.) Wilczek) cultivars 总被引:1,自引:0,他引:1
Greengram [Vigna radiata (L.) Wilczek], also known as mung bean, widely cultivated in a large number of countries, is an important pulse crop of Asia
and is considered one of the ancestral species of the genus Vigna. Since yields of greengram have remained low across subtropical and tropical Asia, it is important to estimate genetic diversity
in existing cultivars in order to see if the lack of genetic variability might be a constraining factor. In this study, 32
Indian cultivars of greengram were subjected to random amplified polymorphic DNA (RAPD) analysis using 21 decamer primers.
A total of 267 amplification products were formed at an average of 12.71 per primer with an overall polymorphism of 64%. The
extent of polymorphism was moderate to low. Jaccard similarity coefficient values ranged from 0.65 to 0.92. The cluster analysis
resulted in mainly three clusters revealing greater homology between cultivars released from the same source. The results
of principal components analysis also substantiated this conclusion. The close genetic similarity between the cultivars could
be explained due to the high degree of commonness in their pedigrees. The narrow genetic base of the greengram cultivars revealed
in the present analysis emphasises the need to exploit the large germplasm collections having diverse morphoagronomic traits
in cultivar improvement programs.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
20.
The extracellular invertase (β-D-fructofuranoside fructohydrolase, EC 3.2.1.26) was isolated and characterized from the hypocotyls
of mung bean (Phaseolus radiatus L.). The enzyme was purified to apparent homogeneity by ammonium sulfate fractionation and sequential chromatography over
diethylaminoethyl (DEAE)-cellulose anion exchange, Concanavalin (Con) A-Sepharose 4B affinity and Sephadex G-200. The overall
purification was about 77-fold with a recovery of about 11%. The finally purified enzyme exhibited a specific activity of
about 113 μmol of glucose produced mg-1 protein min-1 at pH 5.0 and appeared to be a single protein by nondenaturing polyacrylamide gel electrophoresis (PAGE) and sodium dodecyl
sulfate (SDS)-PAGE. The enzyme had the native molecular mass of 134 kD and subunit molecular weight of 67 kD as estimated
by Sephadex G-200 chromatography and SDS-PAGE, respectively, suggesting that the enzyme was composed of homodimeric proteins.
On the other hand, the enzyme appeared to be a glycoprotein containing mannosyl residues on the basis of its ability to interact
specifically with the immobilized Con A and the separability of invertase-Con A complex by methyl-α-D-mannopyranoside. The
enzyme had a Km for sucrose of 3.4 mM and its pH optimum of 4.0. The enzyme showed highest enzyme activity with sucrose as substrate. Raffinose
and cellobiose were hydrolyzed at a low rate, maltose and lactose were not cleaved by the enzyme. These results indicate the
extracellular invertase is a β-fructofuranosidase. 相似文献