SummaryPolygalacturonase-inhibiting protein (PGIP) i s a cell wall protein purified from hypocotyls of true bean (Phaseolus vulgaris L.). PGlP inhibits fungal endopolygalacturonases and is considered to be an important factor for plant resistance to phytopathogenic fungi (Albersheim and Anderson, 1971; Cervone eta/., 1987). The amino acid sequences of the N-terminus and one internal tryptic peptide of the PGlP purified from P. vulgaris cv. Pinto were used to design redundant oligonucleotides that were successfully utilized as primers in a polymerase chain reaction (PCR) with total DNA of P. vulgaris as a template. A DNA band of 758 bp (a specific PCR amplification product of part of the gene coding for PGIP) was isolated and cloned. By using the 758-bp DNA as a hybridization probe, a lambda clone containing the PGlP gene was isolated from a genomic library of P. vulgaris cv. Saxa. The coding and immediate flanking regions of the PGlP gene, contained on a subcloned 3.3 kb Sall-Sall DNA fragment, were sequenced. A single, continuous ORF of 1026 nt (342 amino acids) was present in the genomic clone. The nucleotide and deduced amino acid sequences of the PGlP gene showed no significant similarity with any known databank sequence. Northern blotting analysis of poly(A)+ RNAs, isolated from various tissues of bean seedlings or from suspension-cultured bean cells, were also performed using the cloned PCR-generated DNA as a probe. A 1.2 kb transcript was detected in suspension-cultured cells and, to a lesser extent, in leaves, hypocotyls, and flowers. A cDNA clone containing part of the coding region for
With the growing demand of fresh-cut vegetables, a variety of packaging films are produced specifically to improve safety and quality of the fresh vegetables over the storage period. The aim of our work was to evaluate the influence of different packaging films on the quality of fresh-cut lettuce analyzing changes in bacterial community composition and modifications at the proteome level, by means of culture-dependent/culture-independent methods and differential gel electrophoresis combined with mass spectrometry analysis. Total viable counts indicated the presence of a highly variable and complex microbial flora, around a mean value of 6.26 log10 CFU g(-1). Analysis of terminal-restriction fragment length polymorphism data indicated that bacterial communities changed with packaging films and time, showing differences in community composition and diversity indices between the commercially available package (F) and the new packages (A and C), in the first days after packaging. Also proteomic analysis revealed significant changes, involving proteins related to energy metabolism, photosynthesis, plant defense and oxidative stress processes, between F and A/C packages. In conclusion, microbiological and proteomic analysis have proved to be powerful tools to provide new insights into both the composition of leaf-associated bacterial communities and protein content of fresh-cut lettuce during the shelf-life storage process.
Polygalacturonase-inhibiting protein (PGIP) is a cell wall protein purified from hypocotyls of true bean (Phaseolus vulgaris L.). PGIP inhibits fungal endopolygalacturonases and is considered to be an important factor for plant resistance to phytopathogenic fungi (Albersheim and Anderson, 1971; Cervone et al., 1987). The amino acid sequences of the N-terminus and one internal tryptic peptide of the PGIP purified from P. vulgaris cv. Pinto were used to design redundant oligonucleotides that were successfully utilized as primers in a polymerase chain reaction (PCR) with total DNA of P. vulgaris as a template. A DNA band of 758 bp (a specific PCR amplification product of part of the gene coding for PGIP) was isolated and cloned. By using the 758-bp DNA as a hybridization probe, a lambda clone containing the PGIP gene was isolated from a genomic library of P. vulgaris cv. Saxa. The coding and immediate flanking regions of the PGIP gene, contained on a subcloned 3.3 kb SalI-SalI DNA fragment, were sequenced. A single, continuous ORF of 1026 nt (342 amino acids) was present in the genomic clone. The nucleotide and deduced amino acid sequences of the PGIP gene showed no significant similarity with any known databank sequence. Northern blotting analysis of poly(A)+ RNAs, isolated from various tissues of bean seedlings or from suspension-cultured bean cells, were also performed using the cloned PCR-generated DNA as a probe. A 1.2 kb transcript was detected in suspension-cultured cells and, to a lesser extent, in leaves, hypocotyls, and flowers.(ABSTRACT TRUNCATED AT 250 WORDS)
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.