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bacteriocin-like substances produced by rhizobium japonicum and other slow-growing rhizobia.bacteriocin-like substances were commonly produced by slow-growing rhizobium japonicum and cowpea rhizobia on an l-arabinose medium. antagonism between strains of r. japonicum was not detected in vitro; however, such strains were often sensitive to some bacteriocins produced by cowpea rhizobia. inhibitory zones (2 to 8 mm from colony margins), produced by 58 of 66 r. japonicum test strains, were reproducibly detected with corynebacterium nebraskense as an indicator. quantitative production was n ...1978570016
an efficient mrna-dependent translation system from reticulocyte lysates.a simple method is described for converting a standard rabbit reticulocyte cell-free extract (lysate) into an mrna-dependent protein synthesis system. the lysate is preincubated with cacl2 and micrococcal nuclease, and then excess ethyleneglycol-bis(2-aminoethylether)-n,n'-tetraacetic acid is added to chelate the ca2+ and inactivate the nuclease. lysates treated in this way have neglibible endogenous amino acid incorporation activity, but 75% of the activity of the original lysate can be recover ...1976823012
salt tolerance of rhizobium species in broth cultures.salt tolerance of five rhizobia strains was examined in broth cultures. five levels of nacl concentration were used and the optical density was taken as a measure for the vigour of bacterial growth. rhizobium leguminosarum and r. meliloti were tolerant to high levels of salinity and growth curves in saline broth showed a similar pattern to the control level. rhizobium japonicum, cowpea rhizobium, and r. trifolii were intolerant to salt and showed a strong growth retardation with increasing salt ...1979547498
nitrate reductase and dehydrogenase activities of cowpea nodules as affected by ammonium sulphate and urea fertilizers. 1978726712
activity of nitrogenase and glutamine synthetase in relation to availability of oxygen in continuous cultures of a strain of cowpea rhizobium sp. supplied with excess ammonium.in samples from nitrogen-fixing continuous cultures of strain cb756 of the cowpea type rhizobia (rhizobium sp.), newly fixed nh+4 is in equiblibrium with the medium, from where it is assimilated by the glutamine synthetase/glutamate synthase pathway. in samples from steady state cultures with different degrees of oxygen-limitation, nitrogenase activity was positively correlated with the biosynthetic of glutamine synthetase in cell free extracts. also, activities in biosynthetic assays were posit ...197823859
the correlation between the efficiency of rhizobia and nitrate reductase and dehydrogenase activities of cowpea nodules.cowpea seeds variety fettriat were planted in nile silt soil and inoculated with 5 strains of cowpea rhizobia. after 50 and 80 days, the plants were uprooted, analysed for dry weight, total nitrogen, fresh weight of nodules, nitrate reductase activity in the leaves, and nitrate reductase and dehydrogenase activities in the nodule homogenate in the presence or absence of succinate, citrate, and ethyl alcohol. the data were analysed to establish the correlation coefficients between total nitrogen ...1978726713
nitrate reductase activities of rhizobia and the correlation between nitrate reduction and nitrogen fixation.all species of rhizobium except r. lupini had nitrate reductase activity. only r. lupini was incapable of growth with nitrate as the sole source of nitrogen. however, the conditions necessary for the induction of nitrate reductase varied among species of rhizobium. rhizobium japonicum and some rhizobium species of the cowpea strains expressed nitrate reductase activities both in the root nodules of appropriate leguminous hosts and when grown in the presence of nitrate. rhizobium trifolii, r. pha ...1979119573
nitrogen fixation in nitrate reductase-deficient mutants of cultured rhizobia.forty-eight mutants unable to reduce nitrate were isolated from "cowpea" rhizobium sp. strain 32hl and examined for nitrogenase activity in culture. all but two of the mutants had nitrogenase activity comparable with the parental sttain and two nitrogenase-defective strains showed alterations in their symbiotic properties. one strain was unable to nodulate either macroptilium atropurpureum or vigna uguiculata and, with the other, nodules appeared promptly, but effective nitrogen fixation was del ...1977838684
protozoa and the decline of rhizobium populations added to soil.a fall in rhizobium abundance occurred in nonsterile soil inoculated with large numbers of the root-nodule bacteria, but many of the rhizobia still survived. no such decline was evident in sterile soil. protozoa feeding on these bacteria were isolated from soil and other environments. as the abundance of rhizobium meliloti and a cowpea rhizobium strain in soil decreased, the protozoan density increased. the inability of the predators to eliminate their prey from soil was not the result of the pr ...1975807307
[bean and rice mixtures of high protein value (author's transl)].the optimum content of different rice (oryza sativa) and bean (vigna unguiculata l.) combinations was studied in albino rats. the mixture containing 3 g of rice proteins, corresponding to 41g of rice "in natura", and 7 g of bean protein, corresponding to 59 g of bean "in natura", presented the highest protein efficiency ratio and the feed efficiency ratio. since the limiting amino acid of this mixture was methionine, new assays using varying levels of this amino acid as a supplement were carried ...1979515465
examination and modification of the use of leuconostoc mesenteroides for measurements of the sulfur-containing amino acids from vigna unguiculata. 1977858858
survival and efficiency of cowpea rhizobia on pelleted and non-pelleted peanut seeds, treated with fungicides.peanut seeds were either normally inoculated with the legume inoculant okadin, containing cowpea rhizobia, or pelleted and treated with each of the fungicides brassical, thiram, orthocide 75, falisan, vitavax 75, and agrosan. the seeds were then incubated at room (+/- 25 degrees c) or refrigeration temperatures (+/- 5 degrees c). survival tests were made after 2 and 10 days. treated seeds were also planted in pots containing nile silt for testing the efficiency of rhizobia as affected by the fun ...1978696041
conformational states of cowpea chlorotic mottle virus ribonucleic acid components.the conditions determining conformational changes in the four ribonucleic acid components of cowpea chlorotic mottle virus have been studied. all four components have at least two electrophoretically separable conformers, the occurrence of which can be regulated by both monovalent and polyvalent cations. this phenomenon also occurs, in a much less striking way, in the ribonucleic acids of the two other members of the bromovirus group, brome mosaic virus and broad bean mottle virus. although spec ...1978643624
comparison of the relationships of southern bean mosaic virus and the cowpea strain of tobacco mosaic virus with the bean leaf beetle. 1978563640
differential stimulation and inhibition of growth of rhizobium trifolii strain t1 and other rhizobium species by various carbon sources.the physiological properties of rhizobium trifolii strain t1 were studied in detail, since this strain has many useful characteristics and appears ideal for development as a reference strain for r. trifolii. some tricarboxylic acid cycle intermediates and related compounds were found to stimulate growth in the presence of sucrose and arabinose, while others inhibited growth partially or completely. other r. trifolii strains behaved likewise. moreover, similar responses were also observed with ot ...1977617211
denitrification in rhizobium.thirty-three strains of rhizobium were examined for their reduction of nitrate under anoxic conditions. three patterns of dissimilatory nitrate reduction were observed: (1) reduction to n2o and n2 (denitrification), (2) reduction to and subsequent accumulation of no2- (nitrate respiration), (3) no reduction. strains of r. japonicum and the cowpea miscellany displayed all three types, while strains of r. leguminosarum, r. phaseoli, and r. trifolii did not reduce nitrate by dissimilatory means. th ...1978667742
occurrence of certain physiological groups of soil micro-organisms in the rhizosphere and rhizoplane of watermelon, cucumber, and cowpea.a field experiment was run for studying the occurrence of ammonifiers, azotobacter, aerobic cellulose-decomposers, and nitrifiers in rhizosphere soils as well as in rhizoplane samples of watermelon, cucumber, or cowpea at different stages of growth. in unamended soil, all the heterotrophs were generally stimulated in the rhizosphere of each plant, especially the leguminous one, resulting in positive rhizosphere effects. in amended soil, on the other hand, both negative and positive (but lower th ...1979545941
fatty acid composition of rhizobium spp.the fatty acid composition of 42 isolates belonging to the major plant affinity groups of rhizobium has been determined and found to vary reproducible with culture age. numerical taxonomic techniques applied to the 15 major fatty acid components of log-phase cultures of comparable physiological age showed that the rhizobia constitute a uniform group. however, two clusters comprising soybean-cowpea isolates and pea-bean isolates were evident. these observations, based on a simple analysis of only ...1979427657
investigation on the infection of cucumber mesophyll protoplasts with cucumber mosaic virus.isolated protoplasts from the first leaf mesophyll of cucumber plants have been successfully infected in vitro with cucumber mosaic virus (cmv). virus instability before, during and after inoculation of the protoplasts resulted in low infectivities when extracts were assayed on cowpea; however, viral rna extraction improved the bioassay technique. attempts to optimize inoculation and incubation of protoplasts are outlined, incorporating the improved assay.197613767
nitrogen fixation in cultured cowpea rhizobia: inhibition and regulation of nitrogenase activity. 197611803
nitrogenase activity in cultured rhizobium sp. strain 32h1: nutritional and physical considerations.nutritional and physical conditions affecting nitrogenase activity in the strain of "cowpea" rhizobia, 32h1, were examined using cultures grown on agar medium. arabinose in the basic medium (cs7) could be replaced by ribose, xylose, or glycerol, but mannitol, glucose, sucrose, or galactose only supported low nitrogenase (c2h2 reduction) activity. succinate could be replaced by pyruvate, fumarate, malate, or 2-oxoglutarate, but without any carboxylic acid, nitrogenase activity was low or undetect ...19765982
further evidence for the regulation of bacterial populations in soil by protozoa.after the addition to soil of large numbers of a cowpea rhizobium strain, the population declined steadily until the numbers reached about 10(7)/g, and the protozoa rose to about 10(4)/g. when indigenous protozoa were suppressed by the addition of actidione to the soil, the density of the test rhizobium did not fall initially, but its abundance declined to about 10(7)/g when actidione-resistant protozoa arose in significant numbers. the addition to actidione-treated soil of an antibiotic-resista ...1977879960
escherichia coli plasmid pbr313 insertion into plant protoplasts and into their nuclei.cowpea mesophyll protoplasts were shown to bind irreversibly up to 3% input radioactive pbr313 plasmid dna after 15 min of contact. maximum uptake occurred in the presence of 5 mm znso4 and 5 microgram/ml poly-l-ornithine. under these conditions about one half of the tca precipitable radioactivity was associated with the nuclear fraction and behaved as linear plasmid molecules. these could not be chased from the protoplasts upon further incubation with unlabeled plasmid dna. the presence of dono ...1977331080
efficient reverse transcription of cowpea mosaic virus rnas.conditions are described which give an efficient synthesis of dna copies of cowpea mosaic virus (cpmv) rnas, using avian myeloblastosis reverse transcriptase and oligo (dt) primers. maximum incorporation of damp into cdna is attained with 0.4 to 0.8 mm of each deoxynucleoside triphosphate, 12 mm mg++ and 60 mm k+ ion concentrations. high enzyme concentrations (up to 100 units/ml) were used. under these conditions over 1000 pmoles of damp were incorporated per reaction. the cdna:rna molar ratio ...197885293
comparison of chemical and microbiological methods in the estimation of methionine in cowpea (vigna unguiculata) seeds.1. meals were prepared from the seeds of fifteen varieties of cowpea (vigna unguiculata), one of lima bean (phaseolus lunatus) and one of yam bean (sphenostylis stenocarpa), and their methionine content was determined by six different methods. 2. total methionine content was determined by two chemical methods (ion-exchange chromatography and a colorimetric procedure) and by two microbiological methods. the 'available' methionine content was determined by microbiological assay with streptococcus ...1976821514
fungi associated with stored unprocessed cowpea and groundnut varieties available in borno state, nigeria.five stored unprocessed cowpea (vigna spp) and four groundnut (arachis hypogeae) varieties available in borno state were examined for the mould flora. the degree of infestation of the grains ranged from 31% to 100% and 68% to 86% for surface sterilized cowpea and groundnut respectively. the mould flora commonly encountered were species of the genera aspergillus. penicillium species, scopulariopsis species and trichoderma species were also found. the flora of the cowpea was dominated by aspergill ...19921300349
differential effect of 2-thiouracil on synthesis of two plant viruses in the same host.in cowpea leaves singly or doubly infected with cowpea chlorotic mottle virus (ccmv) and/or southern bean mosaic virus (sbmv), treatment with 2-thiouracil increased the accumulation of ccmv particles and strongly decreased the accumulation of sbmv particles. thiouracil prevented the usual inhibition of synthesis of ccmv particles at about 6 days after inoculation, and 2-3 times as many ccmv particles accumulated as in water-treated plants. a single treatment of thiouracil 48 h before, at the tim ...1977870449
in vitro and in vivo translation of the ribonucleic acids of a cowpea strain of tobacco mosaic virus. 1976936472
the amino acid sequence of the cowpea strain of tobacco mosaic virus protein.the amino acid sequence of the coat protein of the cowpea strain of tobacco mosaic virus (cowpea virus) has been determined. the tryptic peptide overlaps were obtained by digesting the protein with chymotrypsin and separating and analysing the lysine-and arginine-containing chymotryptic peptides. the primary structure of cowpea virus protein has been found to differ markedly from that of any other known strain of tobacco mosaic virus, and contains 3 amino acid residues more and 96 amino acid cha ...19751138919
toxicity of leucaena leucocephala. the effect of iodine and mineral supplements on penned steers fed a sole diet of leucaena.steers fed a sole diet of leucaena leucocephala cv. peru (leucaena), rapidly developed a hypothyroid condition. total serum thyroxine (t4) levels declined from c 120 n mol litre-1 to 13 n mol litre-1 within six weeks of full leucaena feeding. associated with the hypothyroidism was a declined in feed intake, poor weight gain, hair loss, excessive salivation and the development of lesions on the oesophagus of some animals. light steers (119 kg) were more severely affected than heavy steers (220 kg ...1978718558
tumor induction by agrobacterium tumefaciens prevented in vigna sinensis seedlings systemically infected by ribonucleic acid viruses.cowpea (vigna sinensis) seedlings failed to develop tumors after being inoculated with crown gall bacteria (agrobacterium tumefaciens) if, at times earlier than 1 day later, they were inoculated on the primary leaves with a cowpea mosaic virus that systemically infects them. inoculation with buffer or with a virus that is restricted to a localized infection, or to which the cowpea is immune, did not interfere with the subsequent development of tumors. the virus infection did not appear to affect ...1979422243
siderophore and organic acid production in root nodule bacteria.nineteen strains of root nodule bacteria were grown under various iron regimes (0.1, 1.0 and 20 microm added iron) and tested for catechol and hydroxamate siderophore production and the excretion of malate and citrate. the growth response of the strains to iron differed markedly. for 12 strains (bradyrhizobium strains nc92b and 32h1, b. japonicum usda110 and cb1809, b. lupini wu8, cowpea rhizobium ngr234, rhizobium meliloti strains u45 and cc169, rhizobium leguminosarum bv viciae wu235 and rhizo ...19921387306
use of inactivating agents to detect and partially characterize very early events in the infection of cowpea leaf epidermal cells by peanut stunt virus. 1976948863
characterization of proteins released from legume seeds in hot water.when immersed in water at 50-60 degrees, mature soybean seeds release a large amount of protein. the major protein released was basic 7s globulin (bg), which is present in the cotyledons of soybean seeds. the released bg consisted of the 27,000 and 16,000 subunits which were linked by disulphide bonding and glycosylated. the released bg exhibited an identical structure with the mature bg which was synthesized in the normal developing seeds. proteins like bg were also found to be released into ho ...19921368037
sequence homology adjacent to the 3' terminal poly(a) of cowpea mosaic virus rnas.we have determined the sequence of 80 nucleotides adjacent to 3' poly(a) of both (middle and bottom component) cowpea mosaic virus rnas, using dideoxynucleotide termination of reverse transcription. sequence conservation is indicated, there being about 80% homology between the first 65 bases of each rna. although both rnas are polyadenylated, there is no aauaaa sequence as associated with most known polyadenylated mrnas of eukaryotes and viruses. however both rnas are u and a-rich in this region ...197991160
homogenization-resistant and -susceptible components of tobacco mosaic virus replicative form rna.when prepared from tissue frozen with liquid nitrogen, tobacco mosaic virus replicative form rna (tmv rf) was uniform in size but when prepared by high-speed homogenization, or when tmv rf prepared with liquid nitrogen was homogenized, 80 to 90% of the rf broke into relatively discrete pieces. the unbroken rf was not fragmented by additional homogenization. the tmv rf components susceptible and resistant to breakage, respectively, were synthesized with similar kinetics in relation to length of l ...19761018172
serological and biological relationships among viruses in the bean common mosaic virus subgroup.bean common mosaic virus (bcmv), blackeye cowpea mosaic virus (b1cmv), cowpea aphid-borne mosaic virus (cabmv), azuki bean mosaic virus (azmv), and peanut stripe virus (pstv) are five species of the genus potyvirus, family potyviridae which are seed-transmitted in beans or cowpeas. eighteen isolates of bcmv, five isolates of b1cmv, four isolates of cabmv, and one isolate each of azmv, and pstv were compared serologically using a panel of 13 monoclonal antibodies (mabs) raised against bcmv, b1cmv ...19921450766
cloned dna copies of cowpea severe mosaic virus genomic rnas: infectious transcripts and complete nucleotide sequence of rna 1.cowpea severe mosaic virus (cpsmv) is a member of the comovirus group of messenger-sense rna viruses with bipartite genomes, of which cowpea mosaic virus (cpmv) is the type member. full-length copies of cpsmv rna 1 were cloned in plasmids bearing a bacteriophage t7 promoter. previously, similar clones of cpsmv rna 2 had been obtained. a 5'-ruauuaaaauuuu sequence is common to rna 1 and rna 2. from two rna 1 clones and four rna 2 clones we excised non-cpsmv sequences so as to provide templates for ...19921448917
strains of bean common mosaic virus consist of at least two distinct potyviruses.bean common mosaic virus (bcmv) consists of a large number of pathotypes and strains which have largely been identified by their characteristic interactions with a selected number of differential bean cultivars. the relationships among these strains and other potyviruses that infect legumes are complex, with indications that bcmv, blackeye cowpea mosaic virus (blcmv) and azuki bean mosaic virus (azmv) may be strains of the one virus. using high performance liquid chromatographic peptide profiles ...19921450767
the effect of double-stranded cowpea mosaic viral rna on protein synthesis.the effect of double-stranded cowpea mosaic viral rna on several in vitro protein synthesizing systems was studied. no inhibitory effect of this rna at concentrations up to 16 mug/ml was found in wheat germ protein synthesis programmed with cowpea mosaic viral-, alfalfa mosaic viral- or globin 9 s-rna. at high concentrations of this double-stranded rna, inhibition of escherichia coli in vitro protein synthesis programmed with ms-2- and cowpea mosaic viral-rna was found, whereas at low concentrat ...19751092369
a proposal for a bean common mosaic subgroup of potyviruses.in order to elucidate the taxonomic positions of bean common mosaic virus (bcmv) and blackeye cowpea mosaic virus (b1cmv), several strains of these viruses were compared on the basis of host ranges, antigenic properties established with antisera to virions and to n-terminal peptide domains of their coat proteins, and high performance liquid chromatographic peptide profiles. the comparison includes three strains of bcmv, viz. nl1, nl3 and ny15, four strains of b1cmv, viz. fla, ind, nr, and w, and ...19921450765
proceedings: the cowpea strain of tmv is a pseudo-multicomponent virus. 19761275404
isolation and characterization of rhizobitoxine mutants of bradyrhizobium japonicum.to explore the role of rhizobitoxine in bradyrhizobium-legume symbiosis, 11 rhizobitoxine mutants of b. japonicum usda61 were isolated on the basis of their inability to synthesize the toxin in culture. each mutant is prototrophic and symbiotically effective on soybean, cowpea, siratro, and glycine soja. the rhizobitoxine mutants differ in their chlorosis phenotypes and rhizobitoxine production in planta. as expected, one group of mutant fail to make toxin in planta, resulting in the absence of ...19921317377
[chemical and biological characterization of meal and protein isolates from pumpkin seed (cucurbita moschata)].the present study was carried out in order to check through chemical and biological analyses the nutritional characteristics of pumpkin seed, its delipidized meal and its proteic concentrate, considering its availability, nutritional potential, facility for production in poor soils and the need for new food resources. another objective was to complement the amino acid pattern of pumpkin with others protein sources for human consumption. the results obtained indicate that: raw pumpkin seed meal h ...19921342182
[nutritional and taste properties of canned cowpeas (vigna unguiculata (l.) walp). i. effect of the canning process].the effects of canning in brine on cowpea quality (vigna unguiculata (l.) walp) were determined. beans were steamed-blanched at 100 degrees c for 2 minutes, and then canned and autoclaved at 121 degrees c for 10 minutes. these samples were compared to home-cooked cowpea samples through physicochemical, sensory and biological analyses. significant reductions (p < or = 0.01) in canned bean composition as to values for protein, carbohydrate and fiber were determined when compared to cooked samples. ...19921342165
[nutritional and taste properties of canned cowpeas (vigna unguiculata (l.) walp. ii. effect of storage].in order to evaluate the effects of storage on nutritional and sensory properties of canned cowpea (vigna unguiculata (l.) walp), a batch of 180 cans was stocked at room temperature (22 degrees c to 32 degrees c) for a period of six months. at intervals of 0, 30, 90 and 180 days, 26 samples collected randomly were submitted to physicochemical, sensory and biological analyses. significant statistical reductions (p < or = 0.01 to p < or = 0.05) were observed due to storage time, having this signif ...19921342166
evidence for orthologous seed weight genes in cowpea and mung bean based on rflp mapping.a well saturated genomic map is a necessity for a breeding program based on marker assisted selection. to this end, we are developing genomic maps for cowpea (vigna unguiculata 2n = 22) and mung bean (vigna radiata 2n = 22) based on restriction fragment length polymorphism (rflp) markers. using these maps, we have located major quantitative trait loci (qtls) for seed weight in both species. two unlinked genomic regions in cowpea contained qtls accounting for 52.7% of the variation for seed weigh ...19921361476
interaction between viruses and monoclonal antibodies studied by surface plasmon resonance.an automated biosensor system designed for measuring molecular interactions in real time and without any labelling of the reactants has been used to study the interaction of two animal viruses (vaccinia virus and poliovirus) and two plant viruses (cowpea mosaic virus and tobacco mosaic virus) with monoclonal antibodies. using monoclonal antibodies specific for different conformational states of viral protein, it was found that the virus particles retained their conformational integrity when immo ...19921372280
coat protein properties suggest that azuki bean mosaic virus, blackeye cowpea mosaic virus, peanut stripe virus, and three isolates from soybean are all strains of the same potyvirus.the interrelationship of a number of potyviruses infecting legumes has been investigated by comparing molecular properties of their coat proteins. comparison of the coat proteins by the techniques of amino acid analysis and page was inadequate to distinguish strains from distinct potyviruses. however, high-performance liquid chromatographic peptide profiles of tryptic digests of coat proteins of these legume-infecting potyviruses enabled such assignments to be made. these data indicate that amin ...19921500273
infection of cowpea mesophyll protoplasts with cucumber mosaic virus. 1977929986
a hybrid plant rna virus made by transferring the noncapsid movement protein from a rod-shaped to an icosahedral virus is competent for systemic infection.for many plant rna viruses, multiple viral gene products, including noncapsid movement proteins and capsid proteins, contribute to the spread of infection within plants. the extent to which these factors interact to support infection spread is not known, but, for movement protein mutants of certain viruses, the inability of coinoculated "helper" viruses to complement defective movement has suggested a possible requirement for coadaptation between noncapsid movement proteins and other virus facto ...19921495969
mapping and sequence analysis of the capsid protein gene of cowpea mottle virus.twelve cdna clones were generated, covering approximately 95% of the cowpea mottle virus (cmev) genome from the 3' end to near the 5' end. the entire capsid protein sequence of 1,104 nucleotides was contained in two clones located near the 3' terminus. the codons represented 367 amino acids (m(r) 39,611). the postulated amino acid sequence of cmev capsid protein had 36% homology to turnip crinkle virus and 26% homology to carnation mottle virus in the arm and s domains, but western blots showed ...19921500274
nomenclature and relationships of some brazilian leguminous potyviruses related to bean common mosaic and/or passionfruit woodiness viruses.the main brazilian literature of the last 10 years on potyviruses of leguminous plants related to bean common mosaic virus (bcmv) and/or to passionfruit woodiness virus (pwv) is discussed and summarized. the viruses dealt with are canavalia acronecrosis, mosaico de canavalia, cassia yellow spot, cowpea green vein-banding, cowpea rugose mosaic and cowpea severe mottle. the viruses have similar biological properties, such as a host range restricted mainly to the leguminosae, aphid transmission, se ...19921450754
nitrogenase activity and respiration of cultures of rhizobium spp. with special reference to concentrations of dissolved oxygen.studies of nitrogenase in cultures of the cowpea rhizobia (rhizobium spp.) strains 32h1 and cb756 are reported. preliminary experiments established that, even when agar cultures were grown in air, suspensions of bacteria prepared anaerobically from them were most active at low concentrations of free dissolved o2. consequently, assays for activity used low concentrations of o2, stabilized by adding the nodule pigment leghaemoglobin. in continuous, glutamine-limited cultures of 32h1, nitrogenase a ...1976953022
a regulatory role for the 32k protein in proteolytic processing of cowpea mosaic virus polyproteins.we have studied the regulation of proteolytic processing of the polyproteins encoded by cowpea mosaic virus m-rna and b-rna. for that purpose mutations were introduced in full-length cdna clones of these rnas. rna transcripts were translated in rabbit reticulocyte lysate and the effect of mutations on the processing was analysed. these studies revealed that the 32k protein is released from the 200k b-polyprotein by an intramolecular cleavage and remains associated with the 170k protein, probably ...19921413528
processing of vpg-containing polyproteins encoded by the b-rna from cowpea mosaic virus.to study the processing of putative vpg precursors the expression of specific mutant transcripts derived from a full-length cdna clone of cowpea mosaic virus (cpmv) b-rna was examined in a rabbit reticulocyte lysate system. this study revealed that the 170k protein produced by a b-rna mutant that lacks the 32k coding region was efficiently processed by mainly intramolecular cleavages at three different sites into three sets of proteins of 60k + 110k, 84k + 87k, and 58k + 112k. further cleavage o ...19921413529
sequence upstream of the 24k protease enhances cleavage of the cowpea mosaic virus b rna-encoded polyprotein at the junction between the 24k and 87k proteins.to investigate cleavage at the junction between the cowpea mosaic virus (cpmv) 24k and 87k proteins, plasmids were constructed containing the sequence of bottom-component (b) rna encoding the 110k protein plus a variable length of upstream coding sequence. transcripts derived from these clones were translated in rabbit reticulocyte lysate and the appearance of the 87k protein was used to assess the efficiency of cleavage at the 24k-87k junction. the results show that the 110k protein, containing ...19921604812
a review of toxicity factors in some food and feedingstuffs in the nutrition of man and livestock in nigeria.a review of the toxicity factors in some food and feedingstuffs in the nutrition of man and livestock in nigeria was conducted. the crops reviewed were cassava, cocoyam, guinea corn, cottonseed, soyabean, bambara, groundnut and cowpea. these crops provide cheap sources of carbohydrate and protein in the diets of humans and livestock. however, antinutritional factors inhibit their use. antinutritional or toxic factors associated with them are reviewed and means of detoxifying them for human and l ...19921621369
the nucleotide sequence of parsnip yellow fleck virus: a plant picorna-like virus.the complete sequence of 9871 nucleotides (nts) of parsnip yellow fleck virus (pyfv; isolate p-121) was determined from cdna clones and by direct sequencing of viral rna. the rna contains a large open reading frame between nts 279 and 9362 which encodes a polyprotein of 3027 amino acids with a calculated m(r) of 336212 (336k). a pyfv polyclonal antiserum reacted with the proteins expressed from phage carrying cdna clones from the 5' half of the pyfv genome. comparison of the polyprotein sequence ...19921469358
structure determination of the bacteriophage phix174.the structure of the single-stranded dna phage phix174 has been determined to 3.4 a resolution. the crystal space group was p2(1) with one icosahedral particle per asymmetric unit, giving 60-fold noncrystallographic redundancy. oscillation diffraction photographs were collected using synchrotron radiation at various wavelengths. the particle orientations in the unit cell were determined with a rotation function. because cowpea mosaic virus has a similar external envelope to phix174, it was used ...19921418820
the nucleotide sequence and genome organization of the rna2 and rna3 segments in broad bean mottle virus.complete nucleotide sequences of broad bean mottle virus (bbmv) genomic rnas 2 and 3 were determined. they consist of 2811 and 2293 nucleotides, respectively. both rnas are caped and, unlike in other tricornaviruses, both initiate with an a residue. bbmv rna2 is monocistronic and encodes an 815 amino acid 2a protein, whereas rna3 is dicistronic, encoding for a 295 amino acid 3a protein and for the 190 amino acid coat protein. a central, 423 amino acid 2a protein core region is highly homologous ...19921546462
nucleotide sequence and genetic map of cowpea severe mosaic virus rna 2 and comparisons with rna 2 of other comoviruses.we report the nucleotide sequence of cowpea severe mosaic comovirus (cpsmv) genomic rna 2. the molecule is composed of 3732 nucleotide (nt) residues, exclusive of the polyadenylate at the 3' end. only one of the six reading frame registers has a long open reading frame, from nt 255 to nt 3260 in the polarity of encapsidated rna and corresponding to a polyprotein of 1002 amino acid residues (aa). as has been reported for other comoviruses, a second in-frame aug, at nt position 531, apparently als ...19921546463
effect of actinomycin d on replication of satellite tobacco ringspot virus rna in plant protoplasts.we have developed a three-component system of host, tobacco ringspot virus (tobrv), and satellite tobacco ringspot virus rna (stobrv rna) for investigating the specific contributions of host components or tobrv gene products to the propagative cycle of satellite rna. cowpea (vigna unguiculata) protoplasts were inoculated with stobrv and tobrv genomic rnas by electroporation. an increase in stobrv rna was detected both by blot hybridization and by incorporation of [14c]uridine into material with ...19901693804
effects of site-directed mutagenesis on the presumed catalytic triad and substrate-binding pocket of grapevine fanleaf nepovirus 24-kda proteinase.grapevine fanleaf nepovirus (gflv) has a bipartite plus-sense rna genome. its structural and functional proteins originate from polyprotein maturation by at least one virus-encoded proteinase. here we describe the cloning of the 24-kda proteinase cistron located between the virus-linked protein (vpg) and the rna-dependent rna polymerase cistron in gflv rna1 (nucleotides 3966 to 4622). proteinase expressed from this clone is able to cleave gflv polyprotein p2 in order to produce the coat protein ...19921519363
detection of alternative nitrogenases in aerobic gram-negative nitrogen-fixing bacteria.strains of aerobic, microaerobic, nonsymbiotic, and symbiotic dinitrogen-fixing bacteria were screened for the presence of alternative nitrogenase (n2ase) genes by dna hybridization between genomic dna and dna encoding structural genes for components 1 of three different enzymes. a nifdk gene probe was used as a control to test for the presence of the commonly occurring mo-fe n2ase, a vnfdgk gene probe was used to show the presence of v-fe n2ase, and an anfdgk probe was used to detect fe n2ase. ...19911987127
cap structure of u3 small nucleolar rna in animal and plant cells is different. gamma-monomethyl phosphate cap structure in plant rna.u3 small nucleolar rna (snorna) is an abundant small rna involved in the processing of pre-ribosomal rna of eukaryotic cells. u3 snorna has been previously characterized from several sources, including human, rat, mouse, frog, fruit fly, dinoflagellates, slime mold, and yeast; in all these organisms, u3 snorna contains trimethylguanosine cap structure. in all instances where investigated, the trimethylguanosine-capped snrnas including u3 snorna, are synthesized by rna polymerase ii. however, in ...19921618872
site-directed mutagenesis and dna sequence of pcka of rhizobium ngr234, encoding phosphoenolpyruvate carboxykinase: gluconeogenesis and host-dependent symbiotic phenotype.we have cloned and sequenced the pcka gene of rhizobium sp. ngr234, a broad host-range strain. the gene encodes phosphoenolpyruvate carboxykinase (pepck), a key enzyme of gluconeogenesis. the locus was isolated and subcloned from a genomic library of ngr234 employing hybridization with an r. meliloti pck gene probe and complementation of a tn5 mutant in this species. the dna sequence of pcka (ngr234) was determined and encoded a pepck protein of 535 amino acids with a molecular weight of 58.4 kd ...19911720862
nutritional evaluation of the trypsin (ec 3.4.21.4) inhibitor from cowpea (vigna unguiculata walp.).the effect of feeding rats purified cowpea (vigna unguiculata walp.) trypsin (ec 3.4.21.4) inhibitor in a semi-synthetic high-quality diet based on lactalbumin (10 g inhibitor/kg) for 10 d was a moderate reduction in the weight gain of rats in comparison with controls, despite an identical food intake in the two groups. the reduction in the growth rate was about 20% on a live weight basis. however, the corresponding value calculated from the weight of dry carcasses was less, only about 7%, proba ...19921493140
the mechanism of translation of cowpea mosaic virus middle component rna: no evidence for internal initiation from experiments in an animal cell transient expression system.the possibility that internal initiation of translation is responsible for the synthesis of the middle component (m) rna-encoded 95k protein of cowpea mosaic virus (cpmv) has been investigated by constructing plasmids in which the entire sequence of cpmv m rna was cloned downstream of a chloramphenicol acetyltransferase gene. expression of these plasmids in an animal cell expression system revealed that no synthesis of the proteins encoded by the downstream cpmv open reading frame takes place fr ...19911765773
expression of cowpea mosaic virus coat protein precursor in transgenic tobacco plants.tobacco, nicotiana tabacum l., supports cowpea mosaic virus (cpmv) replication and cell-to-cell movement, and thus may serve as a model system to study coat protein-mediated protection against cpmv. a chimeric gene consisting of the cauliflower mosaic virus 35s promoter, cpmv 60k coat proteins-precursor (cp-p) coding region, and the nopaline synthase polyadenylation signal was transferred to tobacco cv. burley 21 via the agrobacterium tumefaciens binary vector system. gene integration and expres ...19921730936
the requirement for a 5' stem-loop structure in brome mosaic virus replication supports a new model for viral positive-strand rna initiation.sequences with strong similarity to internal control regions 1 and 2 (icr1 and -2; a and b boxes) of trna genes are found at the 5' termini of the genomic rnas of brome mosaic virus (bmv) and other plant viruses. the functionality of these motifs was studied by introducing point mutations into the icr2-like sequence of prna-2 m/s, a bmv rna-2 deletion mutant that replicates in the presence of rnas-1 and -2 but does not encode a functional viral protein. the accumulation of positive-strand progen ...19921731107
do rhizobia produce cytokinins?two rhizobium strains were cultured on a defined medium; one was a normal strain of the cowpea group (anu240) while the other (ic3342) was an unusual but related strain of the same group which induced abnormal shoot development, including proliferation of lateral buds, in nodulated plants. culture supernatants were examined for the presence of cytokinins by mass spectrometry using deuterium-labelled internal standards and by radioimmunoassay. in culture supernatants of both strains a range of cy ...19911768251
effect of ten antibiotics on the recovery of seed-borne pseudomonas syringae pv syringae of cowpea, vigna unguiculata (l.) walp var. it 825-2246-4.the effect of ten different antibiotics: amoxil, ampicillin, chloramphenicol, cloxacillin, cotrimexazole, erythromycin, nitrofurantoin, penicillin, tetracycline and vibramycin on the recovery of seed-borne pseudomonas syringae pv. syringae and on percentage seed germination of cowpea, vigna unguiculata(l.) walp var. it 825-2246-4 at various temperature regimes: 25 degrees c, 30 degrees c, 35 degrees c and 40 degrees c were investigated using the standard blotter method. seeds were presoaked for ...19911814865
substantial portions of the 5' and intercistronic noncoding regions of cowpea chlorotic mottle virus rna3 are dispensable for systemic infection but influence viral competitiveness and infection pathology.cowpea chlorotic mottle virus (ccmv) has a tripartite, positive strand rna genome. genomic rna3 (2.2 kb) encodes the 3a nonstructural protein and the coat protein, which are dispensable for viral rna synthesis in protoplasts, but required for systemic infection of whole plants. in protoplasts, portions of the 5' and intercistronic noncoding regions of ccmv rna3 are also dispensable for rna3 replication and for transcription of the subgenomic coat protein mrna. to determine whether these noncodin ...19921736532
nodsu, two new nod genes of the broad host range rhizobium strain ngr234 encode host-specific nodulation of the tropical tree leucaena leucocephala.rhizobium species strain ngr234 nodulates at least 35 diverse genera of legumes as well as the nonlegume parasponia andersonii. most nodulation genes are located on the 500-kilobase pair symbiotic plasmid, pngr234a. previously, three plasmid-borne host range determinants (hsni, hsnii, and hsniii) were identified by their ability to extend the nodulation capacity of heterologous rhizobia to include vigna unguiculata. in this study, we show that hsnii contains two new nod-box linked hsn genes, nod ...19902134856
mutational analysis of the putative catalytic triad of the cowpea mosaic virus 24k protease.to investigate the mechanism of action of the cowpea mosaic virus (cpmv) 24k protease, a full-length cdna clone of bottom component (b) rna has been constructed from which rna can be transcribed in vitro using t7 rna polymerase. translation of the resulting rna in rabbit reticulocyte lysate leads to the synthesis of a 200 kda product (the 200k protein) which cleaves itself in a manner identical to that of the product translated from b rna isolated from virions. site-directed mutagenesis of the f ...19911887592
potassium salts influence the fidelity of mrna translation initiation in rabbit reticulocyte lysates: unique features of encephalomyocarditis virus rna translation.it is widely assumed that in vitro translation of mrna is more efficient in the presence of potassium acetate rather than kcl, that the optimum concentration of potassium acetate is higher than for kcl, and that uncapped rnas exhibit a lower optimum salt concentration than capped mrnas. when these assumptions were examined using several different mrna species in four batches of rabbit reticulocyte lysate, some notable exceptions were found. the translation of encephalomyocarditis virus (emcv) rn ...19911849749
ubiquitinated conjugates are found in preparations of several plant viruses.recently d.d. dunigan, r.g. dietzgen, j.e. schoelz, and m. zaitlin (virology 165, 310-312, 1988) demonstrated that a small proportion of the subunits of tobacco mosaic virus particles were conjugated with the small protein ubiquitin. we have now detected ubiquitinated conjugates in immunoblots of virion preparations of several other plant viruses, using anti-human ubiquitin antiserum. based on their polyacrylamide gel migrations, plant virus-associated ubiquitin-immunoreactive proteins were cons ...19902162109
diet-induced changes in the male reproductive system of rats.either quantitative or qualitative modification of diet interferes markedly with the reproductive functions of the rat. the effect of chick mash or cowpeas (vigna unquiculata) on body growth, accessory sex organ weights, serum testosterone, and epididymal histology was studied. body growth was markedly decreased in cowpeas fed group. binucleated, multinucleated giant cells (mgcs), and lymphocytes were found in large numbers in the lumen of caput and cauda epididymis of the cowpea-fed group. no n ...19921503524
use of kanwa-cooked cowpea (vigna unguiculata) in infant food formulation: effect on protein utilization and digestibility. 19902213993
distribution of enterotoxigenic staphylococcus aureus in ready-to-eat foods in eastern nigeria.out of 880 samples of commonly consumed meat, fish and vegetable ready-to-eat foods from eastern nigeria examined, 552 (62%) yielded coagulase-positive staphylococcus aureus, with 269 (48%) of the strains being enterotoxigenic. two cowpea-based foods, akara and moin moin, whose methods of preparation and sale involve little or no post-processing hand contact, contained the smallest numbers of s. aureus. all the water samples from food preparation centres analysed, which had repeated hand contact ...19912049290
use of bromovirus rna3 hybrids to study template specificity in viral rna amplification.brome mosaic virus (bmv) and cowpea chlorotic mottle virus (ccmv) are related positive-strand rna viruses with genomes divided among rnas 1, 2, and 3. rnas 1 and 2 encode the viral rna replication factors, which share extensive conservation with proteins encoded by the animal alphaviruses and diverse plant viruses. in barley protoplasts, ccmv rnas 1 and 2 support high but distinguishable amplification of either bmv rna3 (b3) or ccmv rna3 (c3), while bmv rnas 1 and 2 show even greater discriminat ...19912041089
ecology of accelerated natural lactic fermentation of sorghum-based infant food formulas.accelerated natural lactic fermentation of mixed sorghum-cowpea (formula 1) and sorghum-milkpowder (formula 2) infant food formulas was achieved by repetitive (60 fermentation cycles of 24 h each) use of the previous batch as an inoculum at a rate of 10% (w/w) and resulted in a gradual establishment of mixed populations of lactic acid bacteria and yeasts. in formula 1, early fermentation stages (fermentation cycles 1-4) were dominated by leuconostoc and lactococcus spp. which caused conditions i ...19912049286
evidence for dissimilar properties of comoviral and picornaviral rna polymerases.the poliovirus rna polymerase has been synthesized in spodoptera frugiperda cells by using the baculovirus expression system. crude sonicates of these cells exhibited an rna-elongating activity of a synthetic oligo(u) primer with poly(a) or cowpea mosaic virus (cpmv) rna as a template. a similar polymerase activity was found in extracts of insect cells in which foot-and-mouth disease virus (fmdv) proteins, including the putative polymerase, were produced. the analogous cpmv 87k protein and sever ...19911848591
nucleotide sequence of tomato aspermy virus rna 2.rna 2 of the v strain of tomato aspermy virus (tav) consists of 3074 nucleotides and contains one open reading frame of 2487 nucleotides. thus, it resembles rna 2 of cucumber mosaic virus (cmv) strains q and fny (62% identical to both), brome mosaic virus (42% identical) and cowpea chlorotic mottle virus (40% identical). in comparisons between amino acid sequences, three different regions of similarity could be distinguished. these were the central part (amino acids 224 to 757 for v-tav), which ...19912016592
nucleotide sequence of tomato ringspot virus rna-2.the sequence of tomato ringspot virus (tomrsv) rna-2 has been determined. it is 7273 nucleotides in length excluding the 3' poly(a) tail and contains a single long open reading frame (orf) of 5646 nucleotides in the positive sense beginning at position 78 and terminating at position 5723. a second in-frame aug at position 441 is in a more favourable context for initiation of translation and may act as a site for initiation of translation. the tomrsv rna-2 3' noncoding region is 1550 nucleotides ...19911856689
the atp requirement for initiation of eukaryotic translation varies according to the mrna species.the requirement for atp for initiation of eukaryotic mrna translation was tested using gel-filtered rabbit reticulocyte lysates incubated with labelled met-trnafmet and exogenous rna templates, and assaying the formation of labelled 80s initiation complexes in the presence of gtp, or labelled 40s initiation complexes in the presence of a non-hydrolysable analogue of gtp. initiation complex formation on globin mrna, or on capped viral rnas such as papaya mosaic virus rna and tobacco mosaic virus ...19911889398
the nucleotide sequence and genome organization of the rna-1 segment in two bromoviruses: broad bean mottle virus and cowpea chlorotic mottle virus.the complete nucleotide sequences of the rna-1 segments in broad bean mottle virus (bbmv) and cowpea chlorotic mottle virus (ccmv) were determined. bbmv rna-1 consists of 3158 nucleotides and ccmv rna-1 has 3171 nucleotides. both bbmv and ccmv rna-1 are capped at the 5' end but, unlike in other tricornaviruses, bbmv rna-1 initiates with an a residue. both bbmv and ccmv rna-1 are monocistronic encoding for highly homologous 1a proteins of 966 and 958 amino acids, respectively. the highest homolog ...19911962437
compositional evaluation of some cowpea varieties and some under-utilized edible legumes in nigeria.the nutritive potentials of some cowpea varieties such as ife brown, ife bimpe, it84e-124, k59 and tvx716 and some under-utilized edible legumes grown in nigeria such as pigeon pea (cajanus cajan), lima bean (phaseolus lunatus), lablab bean (dolichos lablab), mucuna bean (mucuna sp.) and sphenostilis sternocarpa have been evaluated with respect to their proximate chemical composition, mineral content and some endogenous toxic constituents. the cowpea varieties contained on the average 22.5 g cru ...19892561305
sequence and analysis of the rpon sigma factor gene of rhizobium sp. strain ngr234, a primary coregulator of symbiosis.we report the nucleotide sequence of the rpon gene from broad-host-range rhizobium sp. strain ngr234 and analyze the encoded rpon protein, a sigma factor. comparative analysis of the deduced amino acid sequence of rpon from ngr234 with sequences from other gram-negative bacteria identified a perfectly conserved rpon box unique to rpon sigma factors. symbiotic regulatory phenotypes were defined for a site-directed internal deletion within the coding sequence of the rpon gene of rhizobium strain n ...19902211497
production of root hair deformation factors by rhizobium meliloti nodulation genes in escherichia coli: hsnd (nodh) is involved in the plant host-specific modification of the nodabc factor.the role of the hsnd (nodh) gene in the determination of the host-specific nodulation ability of rhizobium meliloti was studied by expressing the common nodulation genes (nodabc) with or without the hsnd gene in escherichia coli and testing for biological activity on various leguminous plants. in this way, four categories of plants were established. upon infection with e. coli carrying the nodabc construct, root hair deformation (had) was detected on clovers while the hsnd gene was additionally ...19892562755
vpg-mediated aggregation of potyviral rna.rna prepared from the potyvirus tobacco vein mottling virus contained aggregates of the 9.5 kb genomic rna with electrophoretic mobilities corresponding to 20 and 41 kb species. similar aggregates were present in preparations of the rnas of two other potyviruses. aggregation occurred during or after purification of the rna by sucrose gradient centrifugation and alcohol precipitation and was dependent upon the presence of a protein apparently bound covalently to a region at or near the 5' terminu ...19911990064
genomic rna of an insect virus directs synthesis of infectious virions in plants.newly synthesized virions of flock house virus (fhv), an insect nodavirus, were detected in plant cells inoculated with fhv rna. fhv was found in whole plants of barley (hordeum vulgare), cowpea (vigna sinensis), chenopodium (chenopodium hybridum), tobacco (nicotiana tabacum), and nicotiana benthamiana and in protoplasts derived from barley leaves. virions produced in plants contained newly synthesized rna as well as newly synthesized capsid protein. these results show that the intracellular env ...19902296598
expression of plant virus genes in animal cells: high-level synthesis of cowpea mosaic virus b-rna-encoded proteins with baculovirus expression vectors.the baculovirus expression system has been used to produce non-structural proteins encoded by bottom-component rna (b-rna) of cowpea mosaic virus (cpmv). for this, cdnas containing the 60k, 87k, 110k and 170k protein coding sequences were each provided with an atg start codon and the cdna containing the 60k coding sequence with a taa stop codon immediately downstream of the coding sequence. recombinant baculoviruses were retrieved which harboured the modified b-cdna sequences under the control o ...19902254749
flatulence and other discomforts associated with consumption of cowpea (vigna unguiculata).abdominal discomfort after eating cowpeas is known to be a major constraint on their greater consumption. problems associated with cowpea consumption were identified by questionnaire in 448 randomly selected families. some (28%) of the respondents had never experienced flatulence. those who did said it occurred when cowpeas were eaten at all (16.7%), as dinner (42%) or without other foods (15%). a subsample of 40 people who complained of serious abdominal discomfort were fed cowpeas cooked by ei ...19892596840
use of bromovirus rna2 hybrids to map cis- and trans-acting functions in a conserved rna replication gene.brome mosaic virus (bmv) and cowpea chlorotic mottle virus (ccmv) are related positive-strand rna viruses with tripartite genomes. rna replication by either virus requires genomic rnas 1 and 2, which encode protein 1a and the polymeraselike, 94-kilodalton 2a protein, respectively. proteins 1a and 2a share extensive sequence similarity with proteins encoded by a wide range of other positive-strand rna viruses of animals and plants. heterologous combinations of bmv and ccmv rnas 1 and 2 do not sup ...19902293671
cis-acting sequences required for in vivo amplification of genomic rna3 are organized differently in related bromoviruses.cowpea chlorotic mottle virus (ccmv) is a positive-strand rna virus that infects dicotyledonous plants. the genome comprises three capped rnas: rna1 (3.2 kb), rna2 (2.9 kb), and rna3 (2.1 kb). cis-acting sequences required for amplification in vivo were explored for rna3, which does not contribute trans-acting factors to viral rna replication. using a ccmv cdna expression system, deletions throughout rna3 were constructed and tested for successful replication in barley protoplasts coinoculated w ...19902305551
regeneration of a functional rna virus genome by recombination between deletion mutants and requirement for cowpea chlorotic mottle virus 3a and coat genes for systemic infection.rnas 1 and 2 of the tripartite cowpea chlorotic mottle virus (ccmv) genome are sufficient for rna replication in protoplasts, whereas systemic infection of cowpea plants additionally requires rna3, which encodes the 3a noncapsid protein and coat protein. by using biologically active ccmv cdna clones, we find that deletions in either rna3 gene block systemic infection. thus, though some plant rna viruses are able to spread systemically without encapsidation, both the coat and 3a genes are require ...19902308940
proposed regulatory pathway encoded by the nodv and nodw genes, determinants of host specificity in bradyrhizobium japonicum.bradyrhizobium japonicum is the root nodule endosymbiont of soybean (glycine max), mung bean (vigna radiata), cowpea (vigna unguiculata), and siratro (macroptilium atropurpureum). we report the characteristics of a nodulation-gene region of b. japonicum that contributes only marginally to the bacterium's ability to nodulate soybean but is essential for the nodulation of the three alternative hosts. this dna region consists of two open reading frames designated nodv and nodw. the predicted amino ...19902320582
rna2 of grapevine fanleaf virus: sequence analysis and coat protein cistron location.the nucleotide sequence of the genomic rna2 (3774 nucleotides) of grapevine fanleaf virus strain f13 was determined from overlapping cdna clones and its genetic organization was deduced. two rapid and efficient methods were used for cdna cloning of the 5' region of rna2. the complete sequence contained only one long open reading frame of 3555 nucleotides (1184 codons, 131k product). the analysis of the n-terminal sequence of purified coat protein (cp) and identification of its c-terminal residue ...19902374004
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