Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:3.2.1.15 (
pectinase
)
2,440
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Tomato fruit maturation is accompanied by a depolymerization of cell wall pectins which is due to the action of
endopolygalacturonase
(endoPG) preceded by pectin methylesterase (PE) activity. To investigate the role of endoPG and PE in determining the structure of green bean (Phaseolus vulgaris L.) pectins, these pectinases were studied during pod development. Early developmental stages displayed low endoPG or exoPG activities while PE activities were measurable during all stages of pod and seed development. These results do not favour a possible synergistic action of PE and PG. For seeds, the relatively high PE activities concurred with relatively low levels of pectin methyl esterification. At a molecular level, one partial chromosomal clone of 210 bp (PE1V), two partial PE cDNA clones of 660 bp (PE2V and PE3V) from cv. verona and one full-length PE cDNA clone of 1990 bp (PE3M), from cv. Masai were isolated. The identity of the
CDNA
clones was confirmed by expression in Escherichia coli and immunodetection with antibodies directed towards a tomato fruit PE. Transcripts corresponding with the genomic clone PE1V were not detected but both PE2 and PE3 cDNAs corresponded with mRNAs 1.8 kb in length. In contrast to PE2, PE3 gene expression levels varied significantly in pods from different cultivars suggesting an involvement in determining pod morphology.
...
PMID:Characterization of pectinases and pectin methylesterase cDNAs in pods of green beans (Phaseolus vulgaris L.). 891 30
Mold diseases, caused by fungal complexes including Alternaria, Cochliobolus, and Fusarium species, limit sorghum grain production. Media were tested by plating Fusarium thapsinum, Alternaria sp., and Curvularia lunata, individually and competitively.
Dichloran
chloramphenicol rose bengal (DRBC) and modified V8 juice (ModV8) agars, found to be useful, were compared with commonly used agar media, dichloran chloramphenicol peptone (DCPA) and pentachloronitrobenzene (PCNB). Radial growth, starting with mycelia or single-conidia and hyphal tips, demonstrated an effect of media. For isolation of grain fungi, DRBC and ModV8 were similar or superior to DCPA and PCNB. When seedlings were inoculated with conidia of C. lunata, Alternaria sp., F. thapsinum, or mixtures, the percentage of root infection ranged from 28% to 77%. For mixed inoculations, shoot weights, lesion lengths, and percentage of root infections were similar to F. thapsinum inoculations; most colonies recovered from roots were F. thapsinum. For Alternaria grain isolates, 5 morphological types, including Alternaria alternata, were distinguished by colony morphologies and conidial dimensions. Sequence analysis using a portion of the
endo-polygalacturonase
gene was able to further distinguish isolates. Cochliobolus isolates were identified morphologically as C. lunata, Curvularia sorghina, and Bipolaris sorghicola. Multiple molecular genotypes were apparent from rRNA internal transcribed spacer region sequences from Cochliobolus grain isolates.
...
PMID:Isolation and characterization of the grain mold fungi Cochliobolus and Alternaria spp. from sorghum using semiselective media and DNA sequence analyses. 2346 15
Amendment of soil with Trichoderma koningii strain Tr5 grown on autoclaved white millet grain provided between 63 and 79% control of white rot of onion when added to soil containing 10, 25, 50, or 100 sclerotia of Sclerotium cepivorum per kilogram of soil at the time of onion seed sowing. There was no significant difference in the proportion of S. cepivorum infections suppressed among the different sclerotial density treatments. Rhizosphere colonization by T. koningii Tr5 was assessed by incubating onion roots sampled from plants growing in soil with the appropriate density of sclerotia, on a Trichoderma selective medium (Rose bengall-
Allisan
-streptomycin-Previcur agar) developed for the purpose of the study. Trichoderma spp. isolated were typed by comparison of culture morphology as well as
polygalacturonase
(PG) (
EC 3.2.1.15
) and pectinesterase (PE) (EC 3.1.1.11) isozyme profiles to the series of one PG and two PE isozymes known to be produced by T. koningii Tr5. The method was used successfully to assess rhizosphere colonization. Three rates of a millet grain formulation colonized by T. koningii Tr5 were added to soil (1,590, 3,180, and 4,770 kg/ha). At the lowest of these rates, 97% of roots were found to be colonized by isolates which could not be distinguished from T. koningii Tr5, whereas 8% of the roots from nontreated controls were colonized by such isolates. An objective of the study was to determine whether the ability of T. koningii Tr5 to suppress S. cepivorum infections was influenced by increased concentrations of both S. cepivorum sclerotia and T. koningii Tr5-colonized millet grain, and it was found that no further improvements in the percentage of disease suppression were recorded as a result of adding T. koningii Tr5-colonized millet to the soil at more than 1,590 kg/ha at any of the sclerotium concentrations tested.
...
PMID:Effect of Inoculum Density of Sclerotium cepivorum on the Ability of Trichoderma koningii to Suppress White Rot of Onion. 3081 61