{Reference Type}: Journal Article
{Author}: Bleve, Gianluca; Lezzi, Chiara; Spagnolo, Stefano; Tasco, Gianluca; Tufariello, Maria; Casadio, Rita; Mita, Giovanni; Rampino, Patrizia; Grieco, Francesco
{Year}: 2013
{Title}: Roleof the C-terminusof Pleurotus eryngii Ery4 laccase in determining enzyme structure, catalytic properties and stability
{Tag}: 0
{Star}: 0
{Place Published}: Great Clarendon Street, Oxford, OX2 6DP, United Kingdom
{Journal}: Protein Engineering, Design and Selection
{Volume}: 26
{Issue}: 1
{Pages}: 1-13
{Date Displayed}: 2013
{ISBN/ISSN}: 17410126
{Original Publication}: Oxford University Press
{Keywords}: Enzymes; Amino acids; Genes; Substrates; Yeast
{Abstract}: The ERY4 laccase gene of Pleurotus eryngii is not biologically active when expressed in yeast. To explain this finding, we analysed the role of the C-terminus of Ery4 protein by producing a number of its different mutant variants. Two different categories of ERY4 mutant genes were produced and expressed in yeast: (i) mutants carrying C-terminal deletions and (ii) mutants carrying different site-specific mutations at their C-terminus. Investigation of the catalytic properties of the recombinant enzymes indicated that each novel variant acquired different affinities and catalytic activity for various substrates. Our results highlight that C-terminal processing is fundamental for Ery4 laccase enzymatic activities allowing substrate accessibility to the enzyme catalytic core. Apparently, the last 18 amino acids in the C-terminal end of the Ery4 laccase play a critical role in enzyme activity, stability and kinetic and, in particular biochemical and structural data indicate that the K532 residue is fundamental for enzyme activation. These studies shed light on the structure/function relationships of fungal laccases and will enhance the development of biotechnological strategies for the industrial exploitation of these enzymes.   2012 The Author. Published by oxford University Press. All rights reserved.
{Notes}: Compilation and indexing terms, Copyright 2013 Elsevier Inc.
20125115825477
C-terminal domains
C-terminus
Catalytic core
Catalytic properties
Enzymatic activities
Enzyme activation
Enzyme structures
Fungal laccases
Laccase gene
Laccases
Mutant genes
Pleurotus eryngii
Recombinant enzymes
Site-specific
Structural data
Structure/function relationships
Various substrates
{Author Address}: CNR-Istituto di Scienze Delle Produzioni Alimentari (ISPA), via Monteroni, 73100 Lecce, Italy

{Reference Type}: Journal Article
{Author}: Pezzella, C.; Lettera, V.; Piscitelli, A.; Giardina, P.; Sannia, G.
{Year}: 2013
{Title}: Transcriptional analysis of Pleurotus ostreatus laccase genes
{URL}: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=22395908&query_hl=1
{Tag}: 0
{Star}: 0
{Journal}: Appl Microbiol Biotechnol
{Volume}: 97
{Issue}: 2
{Pages}: 705-17
{DOI}: 10.1007/s00253-012-3980-9
{Date Displayed}: 2013 Jan
{Date}: 2013-01-01
{Type of Work}: Journal Article; Research Support, Non-U.S. Gov't
{Accession Number}: 22395908
{Abstract}: Fungal laccases (p-diphenol:oxygen oxidoreductase; EC 1.10.3.2) are multi-copper-containing oxidases that catalyse the oxidation of a great variety of phenolic compounds and aromatic amines through simultaneous reduction of molecular oxygen to water. Fungi generally produce several laccase isoenzymes encoded by complex multi-gene families. The Pleurotus ostreatus genome encodes 11 putative laccase coding genes, and only six different laccase isoenzymes have been isolated and characterised so far. Laccase expression was found to be regulated by culture conditions and developmental stages even if the redundancy of these genes still raises the question about their respective functions in vivo. In this context, laccase transcript profiling analysis has been used to unravel the physiological role played by the different isoforms produced by P. ostreatus. Even if reported results depict a complex picture of the transcriptional responses exhibited by the analysed laccase genes, they were allowed to speculate on the isoform role in vivo. Among the produced laccases, LACC10 (POXC) seems to play a major role during vegetative growth, since its transcription is downregulated when the fungus starts the fructification process. Furthermore, a new tessera has been added to the puzzling mosaic of the heterodimeric laccase LACC2 (POXA3). LACC2 small subunit seems to play an additional physiological role during fructification, beside that of LACC2 complex activation/stabilisation.
{Author Address}: Department of Organic Chemistry and Biochemistry, University of Naples Federico II, via Cinthia 4, 80126 Naples, Italy.
{Language}: eng

{Reference Type}: Journal Article
{Author}: Hu, Meili; Chen, Yan; Wang, Cui; Cui, Huali; Duan, Peilu; Zhai, Tianlong; Yang, Yuling; Li, Shaofei
{Year}: 2013
{Title}: Induction of apoptosis in HepG2 cells by polysaccharide MEP-II from the fermentation broth of Morchella esculenta
{Tag}: 0
{Star}: 0
{Journal}: BIOTECHNOLOGY LETTERS
{Volume}: 35
{Issue}: 1
{Pages}: 1-10
{ISBN/ISSN}: 0141-5492
{Keywords}: FRUITING BODIES; MOREL MUSHROOM; CANCER-CELLS; IN-VITRO; EXTRACT; MYCELIA; MECHANISM; MICE; Apoptosis; HepG2; Morchella esculenta; Polysaccharide; ROS generation
{Abstract}: A novel polysaccharide, MEP-II, isolated from the fermentation broth of Morchella esculenta inhibited the proliferation of human hepatoma cell line (HepG2) through an apoptotic pathway. After HepG2 cells were treated with 150-600 mu g MEP-II/ml, typical apoptotic characteristics including externalization of phosphatidylserine residues on the cell surface, nuclear fragmentation, chromatin condensation and cytoplasm shrinkage were observed. Furthermore, reactive oxygen species (ROS) burst and the collapse of mitochondrial membrane potential (Delta psi m) also occurred in HepG2 cells after incubation of 150-600 mu g MEP-II/ml. The antioxidant, 1 mM N-acetyl-l-cysteine inhibited MEP-II-induced apoptosis, suggesting that ROS are the key mediators for MEP-II-induced apoptosis. MEP-II is therefore a potential anti-tumor agent that induces apoptosis of HepG2 cells through ROS generation.
{Author Address}: Anhui Univ, Sch Life Sci, Hefei 230039, Anhui, Peoples R China; Anhui Univ, Sch Life Sci, Hefei 230039, Anhui, Peoples R China; Anhui Univ, Sch Life Sci, Hefei 230039, Anhui, Peoples R China; Anhui Univ, Sch Life Sci, Hefei 230039, Anhui, Peoples R China; Anhui Univ, Sch Life Sci, Hefei 230039, Anhui, Peoples R China; Anhui Univ, Sch Life Sci, Hefei 230039, Anhui, Peoples R China; Anhui Univ, Sch Life Sci, Hefei 230039, Anhui, Peoples R China; Anhui Univ, Sch Life Sci, Hefei 230039, Anhui, Peoples R China
{Database Provider}: Web of Science SCI
{Language}: English
{Country}: Peoples R China

{Reference Type}: Journal Article
{Author}: Caleb, Oluwafemi J.; Mahajan, Pramod V.; Al-Said, Fahad Al-Julanda; Opara, Umezuruike Linus
{Year}: 2013
{Title}: Modified Atmosphere Packaging Technology of Fresh and Fresh-cut Produce and the Microbial Consequences-A Review
{Tag}: 0
{Star}: 0
{Journal}: FOOD AND BIOPROCESS TECHNOLOGY
{Volume}: 6
{Issue}: 2
{Pages}: 303-329
{ISBN/ISSN}: 1935-5130
{Keywords}: EQUILIBRIUM-MODIFIED ATMOSPHERE; MINIMALLY PROCESSED LETTUCE; ESCHERICHIA-COLI O157-H7; PROTEOLYTIC CLOSTRIDIUM-BOTULINUM; PREDICTIVE FOOD MICROBIOLOGY; MUSHROOMS AGARICUS-BISPORUS; MODELING RESPIRATION RATE; PROTEIN-BASED FILMS; LISTERIA-MONOCYTOGENES; CARBON-DIOXIDE; MAP; Foodborne pathogen; Predictive microbiology; Noble gases; HACCP
{Abstract}: Modified atmosphere packaging (MAP) technology offers the possibility to retard the respiration rate and extend the shelf life of fresh produce, and is increasingly used globally as value adding in the fresh and fresh-cut food industry. However, the outbreaks of foodborne diseases and emergence of resistant foodborne pathogens in MAP have heightened public interest on the effects of MAP technology on the survival and growth of pathogenic organisms. This paper critically reviews the effects of MAP on the microbiological safety of fresh or fresh-cut produce, including the role of innovative tools such as the use of pressurised inert/noble gases, predictive microbiology and intelligent packaging in the advancement of MAP safety. The integration of Hazard Analysis and Critical Control Points-based programs to ensure fresh food quality and microbial safety in packaging technology is highlighted.
{Author Address}: Univ Stellenbosch, Postharvest Technol Res Lab, S African Res Chair Postharvest Technol, Fac AgricSci, ZA-7602 Stellenbosch, South Africa; Natl Univ Ireland Univ Coll Cork, Dept Proc & Chem Engn, Cork, Ireland; Sultan Qaboos Univ, Dept Crop Sci, Muscat, Oman; Univ Stellenbosch, Postharvest Technol Res Lab, S African Res Chair Postharvest Technol, Fac AgricSci, ZA-7602 Stellenbosch, South Africa
{Database Provider}: Web of Science SCI
{Language}: English
{Country}: South Africa; Ireland; Oman