« Previous AbstractRisk Assessment on Benzene Exposure among Gasoline Station Workers    Next AbstractRealistic personal exposure assessment of air pollutants and health outcomes - A cross-sectional study among Kolkata slum dwellers »

Ann Bot

Title:		Ripening of pepper (Capsicum annuum) fruit is characterized by an enhancement of protein tyrosine nitration
Author(s):		Chaki M; Alvarez de Morales P; Ruiz C; Begara-Morales JC; Barroso JB; Corpas FJ; Palma JM;
Address:		"Group of Antioxidants, Free Radicals and Nitric Oxide in Biotechnology, Food and Agriculture, Department of Biochemistry, Cell and Molecular Biology of Plants, Estacion Experimental del Zaidin, CSIC, Apartado 419, 18008 Granada, Spain and. Group of Biochemistry and Cell Signaling in Nitric Oxide. Department of Biochemistry and Molecular Biology, University of Jaen, 23071 Jaen, Spain. Group of Antioxidants, Free Radicals and Nitric Oxide in Biotechnology, Food and Agriculture, Department of Biochemistry, Cell and Molecular Biology of Plants, Estacion Experimental del Zaidin, CSIC, Apartado 419, 18008 Granada, Spain and josemanuel.palma@eez.csic.es"
Journal Title:		Ann Bot
Year:		2015
Volume:		20150326
Issue:		4
Page Number:		637 - 647
DOI:		10.1093/aob/mcv016
ISSN/ISBN:		1095-8290 (Electronic) 0305-7364 (Print) 0305-7364 (Linking)
Abstract:		"BACKGROUND AND AIMS: Pepper (Capsicum annuum, Solanaceae) fruits are consumed worldwide and are of great economic importance. In most species ripening is characterized by important visual and metabolic changes, the latter including emission of volatile organic compounds associated with respiration, destruction of chlorophylls, synthesis of new pigments (red/yellow carotenoids plus xanthophylls and anthocyanins), formation of pectins and protein synthesis. The involvement of nitric oxide (NO) in fruit ripening has been established, but more work is needed to detail the metabolic networks involving NO and other reactive nitrogen species (RNS) in the process. It has been reported that RNS can mediate post-translational modifications of proteins, which can modulate physiological processes through mechanisms of cellular signalling. This study therefore examined the potential role of NO in nitration of tyrosine during the ripening of California sweet pepper. METHODS: The NO content of green and red pepper fruit was determined spectrofluorometrically. Fruits at the breaking point between green and red coloration were incubated in the presence of NO for 1 h and then left to ripen for 3 d. Profiles of nitrated proteins were determined using an antibody against nitro-tyrosine (NO2-Tyr), and profiles of nitrosothiols were determined by confocal laser scanning microscopy. Nitrated proteins were identified by 2-D electrophoresis and MALDI-TOF/TOF analysis. KEY RESULTS: Treatment with NO delayed the ripening of fruit. An enhancement of nitrosothiols and nitroproteins was observed in fruit during ripening, and this was reversed by the addition of exogenous NO gas. Six nitrated proteins were identified and were characterized as being involved in redox, protein, carbohydrate and oxidative metabolism, and in glutamate biosynthesis. Catalase was the most abundant nitrated protein found in both green and red fruit. CONCLUSIONS: The RNS profile reported here indicates that ripening of pepper fruit is characterized by an enhancement of S-nitrosothiols and protein tyrosine nitration. The nitrated proteins identified have important functions in photosynthesis, generation of NADPH, proteolysis, amino acid biosynthesis and oxidative metabolism. The decrease of catalase in red fruit implies a lower capacity to scavenge H2O2, which would promote lipid peroxidation, as has already been reported in ripe pepper fruit"
Keywords:		Capsicum/*growth & development/metabolism Fruit/growth & development/metabolism Nitro Compounds/*metabolism Plant Proteins/*metabolism Proteomics Tyrosine/*metabolism Capsicum annuum Maldi-tof/tof NO gas Rns Solanaceae confocal laser scanning microscopy n;
Notes:		"MedlineChaki, Mounira Alvarez de Morales, Paz Ruiz, Carmelo Begara-Morales, Juan C Barroso, Juan B Corpas, Francisco J Palma, Jose M eng Research Support, Non-U.S. Gov't England 2015/03/31 Ann Bot. 2015 Sep; 116(4):637-47. doi: 10.1093/aob/mcv016. Epub 2015 Mar 26"