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Pectate Lyase (pectate + lyase)

Distribution by Scientific Domains

Life Sciences	18%

Selected Abstracts

Crystallization and preliminary X-ray characterization of a thermostable pectate lyase from Thermotoga maritima

ACTA CRYSTALLOGRAPHICA SECTION D, Issue 4 2002
Michael A. McDonough
Pectate lyase is an enzyme involved in the degradation of the pectate portion of the primary plant cell wall. A recombinant pectate lyase from Thermotoga maritima where three of the four cysteine residues have been mutated (C132I, C156N, C194L) has been crystallized. Crystals of the same morphology and trigonal space group R3 with similar unit-cell parameters were obtained under two different conditions. The first, 0.3,M (NH4)H2PO4 pH 4.2, gave crystals with a maximum size of 0.4 × 0.2 × 0.2,mm in one week that diffracted to a resolution of 1.87,Å and had unit-cell parameters a = b = 80.6, c = 148.8,Å. The second, 0.1,M sodium acetate, 6%(w/v) PEG 4000 pH 6.5, gave the same size crystals in two weeks that diffracted to a resolution of 2.1,Å and had unit-cell parameters a = b = 80.0, c = 150.1,Å. [source]

Purification, crystallization and X-ray analysis of crystals of pectate lyase A from Erwinia chrysanthemi

ACTA CRYSTALLOGRAPHICA SECTION D, Issue 3 2000
Chuong N. Doan
Pectate lyase A is secreted by Erwinia chrysanthemi and is a virulence factor for soft rot diseases in plants. Crystals of pectate lyase A were obtained by vapor-diffusion techniques in the presence of polyethylene glycol. The crystals belong to the monoclinic space group P21, with unit-cell parameters a = 48.96, b = 148.86, c = 78.61,Å, , = 97.32°. The crystals contain two protein molecules of 38,kDa per asymmetric unit and diffract to 2.4,Å using Cu,K, radiation. [source]

Multi-factor regulation of pectate lyase secretion by Colletotrichum gloeosporioides pathogenic on avocado fruits

MOLECULAR PLANT PATHOLOGY, Issue 3 2008
I. MIYARA
SUMMARY Tissue alkalinization during Colletotrichum gloeosporioides attack enhances the expression of PELB, which encodes pectate lyase (PL), and PL secretion, which is considered essential for full virulence. We studied the regulation of PL secretion by manipulation of C. gloeosporioides PELB. PELB was down-regulated by knocking out PAC1, which encodes the PacC transcription factor that regulates gene products with pH-sensitive activities. We functionally characterized a PACC gene homologue, PAC1, from C. gloeosporioides wild-type (WT) Cg-14 and two independent deletion strains, ,pac1372and ,pac1761. Loss-of-function PAC1 mutants showed 85% reduction of PELB transcript expression, delayed PL secretion and dramatically reduced virulence, as detected in infection assays with avocado fruits. In contrast, PELB was up-regulated in the presence of carbon sources such as glucose. When glucose was used as a carbon source in the medium for the WT strain and the ,pac1 mutant at pH 6.0, PELB transcript expression and PL secretion were activated. Other sugars, such as sucrose and fructose (but not galactose), also activated PELB expression. These results suggest that the pH-regulated response is only part of a multi-factor regulation of PELB, and that sugars are also needed to promote the transition from quiescent to active necrotrophic development by the pathogen. [source]

Crystallization and preliminary X-ray characterization of a thermostable pectate lyase from Thermotoga maritima

Characterization of a novel pectate lyase, Pel10A, from Pseudomonas cellulosa

ACTA CRYSTALLOGRAPHICA SECTION D, Issue 8 2001
Simon J. Charnock
Biological recycling of plant material is essential for biosphere maintenance. This perpetual task involves a complex array of enzymes, including extracellular polysaccharide hydrolases and lyases. Whilst much is known about the structure and function of the hydrolases, relatively little is known about the structures and mechanisms of the corresponding lyases. To this end, crystals of the catalytic module of a novel family 10 pectate lyase, Pel10A from Pseudomonas cellulosa, were obtained using polyethylene glycol 2000 monomethylether as a precipitant. They belong to space group P21, with unit-cell parameters a = 47.7, b = 106.1, c = 55.4,Å, , = 92.0°, and have two molecules in the asymmetric unit. The crystals diffract beyond 1.5,Å using synchrotron radiation. [source]

Purification, crystallization and X-ray analysis of crystals of pectate lyase A from Erwinia chrysanthemi

Allergenicity and cross-reactivity of Senecio pollen: identification of novel allergens using the immunoproteomics approach

CLINICAL & EXPERIMENTAL ALLERGY, Issue 6 2008
O. Luengo
Summary Background The genus Senecio is the largest genus of the family Asteraceae (Compositae). The allergenicity of Senecio has not been assessed previously. Objective The aim of this study was to investigate the allergens of Senecio jacobea pollen and to determine their immunological characteristics and clinical relevance. Methods Fifty patients with rhinoconjunctivitis and a positive skin prick test (SPT) to Senecio were recruited. The clinical relevance of this pollen was assessed by means of a nasal provocation test (NPT). Allergens were characterized by one-dimensional electrophoresis (SDS-PAGE) and two-dimensional gel electrophoresis and immunoblotting. Furthermore, characterization and identification of the allergens were performed by mass spectrometry (MS). In vitro inhibition tests were performed to evaluate cross-reactivity with other pollen. Results Three predominant allergens, both in the intensity of reaction and the frequency of recognition by human-allergic sera, were 59 (60%), 42 (50%) and 31 kDa (50%). The two-dimensional analysis allowed the identification of several allergens. One spot around 42 kDa was identified as a protein homologous to pectate lyase and three other spots were homologous to malate dehydrogenase by MS. S. jacobea proteins showed cross-reactivity with other proteins of the Asteraceae family and also with Parietaria judaica. This was demonstrated by immunoblotting and ELISA inhibition studies. Conclusion S. jacobea constitute a newly discovered allergenic source. It shows cross-reactivity with other members of the Asteraceae plant family as well as with P. judaica. [source]

Secretome analysis of novel IgE-binding proteins from Penicillium citrinum

PROTEOMICS - CLINICAL APPLICATIONS, Issue 1 2008
Li-Li Chiu
Abstract The Penicillium genus of fungi is a frequently reported cause of allergic reactions. However, only a limited number of allergens have been reported. In Penicillium spp., many allergens show higher IgE-binding activity in culture filtrate extracts than in cellular extracts. In order to investigate the IgE-reactive profile of mold-sensitized patients, secreted IgE-reactive proteins from Penicillium citrinum were identified by 2-DE, serum immunoblotting, and nanoLC-MS/MS. Among the IgE-reactive spots, one known allergen, Pen c 13, and four novel allergens were identified. The cDNAs coding for Pen c 32 and Pen c 30 were cloned using designed primers based on nanoLC-MS/MS analysis. The amino acid sequences of Pen c 32 and Pen c 30 were, respectively, found to have extensive similarity with those of pectate lyases and catalases from various fungi. Native Pen c 30 was shown to have catalase activity and to bind to serum IgE from 48% of mold-allergic patients and induced immediate type skin reactions in a sensitized patient. Here, we present a proteome approach which resulted in the identification of four novel secreted allergens. These novel allergens might be useful in allergy diagnosis and in the treatment of mold-allergic disorders. [source]