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)
Tissue maceration was generally elucidated by the action of
endo-polygalacturonase
and endo-pectate or -pectin lyase (endo-
PAL
or -PNL). In a process of screening of Erwinia and Pseudomonas strains for enzymatic pulping of pectocellulosic bast fibers, it was found that their
PAL
productivity was not completely related with defibration activity, i.e., the fact that an E.chrysanthemi strain showed high
PAL
productivity but possessed rather low defibration activity. Moreover, defibration activity was parallel to the amount of neutral sugars released during pulping. Based on these fact, the maceration or enzymatic pulping of basts was estimated to proceed not only by cleavage of interfiber bonding cause by
PAL
action but also another factors. Among three possibilities proposed on the maceration mechanism of basts, it was elucidated by a concerted action of
PAL
and PNL with an aid of xylanase. In addition, a quantitative determinative method of maceration activity toward basts was also presented.
...
PMID:Approach to maceration mechanism in enzymatic pulping of bast fibers by alkalophilic pectinolytic enzymes produced by Erwinia species. 1454 40
Lanelate navel orange (
Citrus sinensis
Osbeck) is a late-ripening citrus cultivar increasingly planted in China. The physiological disorder juice sac granulation often occurs in the fruit before harvest, but the physiological and molecular mechanisms underlying this disorder remain elusive. In this study, we found that fruit granulation of the late-ripening navel orange in the Three Gorges area is mainly caused by the low winter temperature in high altitude areas. Besides, dynamic changes of water content in the fruit after freezing were clarified. The granulation of fruit juice sacs resulted in increases in cell wall cellulose and decreases in soluble solid content, and the cells gradually became shrivelled and hollow. Meanwhile, the contents of pectin, cellulose, and lignin in juice sac increased with increasing degrees of fruit granulation. The activities of pectin methylesterase (PME) and the antioxidant enzymes peroxidase (POD), superoxide dismutase, and catalase increased, while those of
polygalacturonase
(PG) and cellulose (CL) decreased. Furthermore, a total of 903 differentially expressed genes were identified in the granulated fruit as compared with non-disordered fruit using RNA-sequencing, most of which were enriched in nine metabolic pathways, and qRT-PCR results suggested that the juice sac granulation is closely related to cell wall metabolism. In addition, the expression of
PME
involved in pectin decomposition was up-regulated, while that of
PG
was down-regulated. Phenylalanine ammonia lyase (
PAL
), cinnamol dehydrogenase (
CAD
), and
POD
related to lignin synthesis were up-regulated, while
CL
involved in cellulose decomposition was down-regulated. The expression patterns of these genes were in line with those observed in low-temperature treatment as revealed by qRT-PCR, further confirming that low winter temperature is associated with the fruit granulation of late-ripening citrus. Accordingly, low temperature would aggravate the granulation by affecting cell wall metabolism of late-ripening citrus fruit.
...
PMID:Transcriptome Analysis Unravels Metabolic and Molecular Pathways Related to Fruit Sac Granulation in a Late-Ripening Navel Orange (
Citrus sinensis
Osbeck). 3194 Aug 26