Characterization and Dye Decolorization Potential of Two Laccases from the Marine-Derived Fungus Pestalotiopsis sp.

: Two laccase-encoding genes from the marine-derived fungus Pestalotiopsis sp. have been cloned in Aspergillus niger for heterologous production, and the recombinant enzymes have been characterized to study their physicochemical properties, their ability to decolorize textile dyes for potential biotechnological applications, and their activity in the presence of sea salt. The optimal pH and temperature of PsLac1 and PsLac2 differed in relation to the substrates tested, and both enzymes were shown to be extremely stable at temperatures up to 50 °C, retaining 100% activity after 3 h at 50 °C. Both enzymes were stable between pH 4-6. Different substrate specificities were exhibited, and the lowest Km and highest catalytic efficiency values were obtained against syringaldazine and 2,6-dimethoxyphenol (DMP) for PsLac1 and PsLac2, respectively. The industrially important dyes-Acid Yellow, Bromo Cresol Purple, Nitrosulfonazo III, and Reactive Black 5-were more efficiently decolorized by PsLac1 in the presence of the redox mediator 1-hydroxybenzotriazole (HBT). Activities were compared in saline conditions, and PsLac2 seemed more adapted to the presence of sea salt than PsLac1. The overall surface charges of the predicted PsLac three-dimensional models showed large negatively charged surfaces for PsLac2, as found in proteins for marine organisms, and more balanced solvent exposed charges for PsLac1, as seen in proteins from terrestrial organisms.

Pycnoporus cinnabarinus glyoxal oxidases display differential catalytic efficiencies on 5-hydroxymethylfurfural and its oxidized derivatives.

BACKGROUND: 5-Hydroxymethylfurfural (HMF), a major residual component of a lignocellulosic bio-refinery process, can be transformed into fundamental building blocks for green chemistry via oxidation. While chemical methods are well established, interest is also being directed into the enzymatic oxidation of HMF into the bio-plastic precursor 2,5-furandicarboxylic acid (FDCA). RESULTS: We demonstrate that three glyoxal oxidases (PciGLOX) isoenzymes from the Basidiomycete fungus Pycnoporus cinnabarinus were able to oxidize HMF, with PciGLOX2 and PciGLOX3 being the most efficient. The major reaction product obtained with the three isoenzymes was 5-hydroxymethyl-2-furancarboxylic (HMFCA), a precursor in polyesters and pharmaceuticals production, and very little subsequent conversion of this compound was observed. However, small concentrations of FDCA, a substitute for terephthalic acid in the production of polyesters, were also obtained. The oxidation of HMF was significantly boosted in the presence of catalase for PciGLOX2, leading to 70% HMFCA yield. The highest conversion percentages were observed on 2,5-furandicarboxaldehyde (DFF), a minor product from the reaction of PciGLOX on HMF. To bypass HMFCA accumulation and exploit the efficiency of PciGLOX in oxidizing DFF and 5-formyl-2-furan carboxylic acid (FFCA) towards FDCA production, HMF was oxidized in a cascade reaction with an aryl alcohol oxidase (UmaAAO). After 2 h of reaction, UmaAAO completely oxidized HMF to DFF and further to FFCA, with FDCA only being detected when PciGLOX3 was added to the reaction. The maximum yield of 16% FDCA was obtained 24 h after the addition of PciGLOX3 in the presence of catalase. CONCLUSIONS: At least two conversion pathways for HMF oxidation can be considered for PciGLOX; however, the highest selectivity was seen towards the production of the valuable polyester precursor HMFCA. The three isoenzymes showed differences in their catalytic efficiencies and substrate specificities when reacted with HMF derivatives.

Recommended names for pleomorphic genera in Dothideomycetes.

This paper provides recommendations of one name for use among pleomorphic genera in Dothideomycetes by the Working Group on Dothideomycetes established under the auspices of the International Commission on the Taxonomy of Fungi (ICTF). A number of these generic names are proposed for protection because they do not have priority and/or the generic name selected for use is asexually typified. These include: Acrogenospora over Farlowiella; Alternaria over Allewia, Lewia, and Crivellia; Botryosphaeria over Fusicoccum; Camarosporula over Anthracostroma; Capnodium over Polychaeton; Cladosporium over Davidiella; Corynespora over Corynesporasca; Curvularia over Pseudocochliobolus; Elsinoë over Sphaceloma; Excipulariopsis over Kentingia; Exosporiella over Anomalemma; Exserohilum over Setosphaeria; Gemmamyces over Megaloseptoria; Kellermania over Planistromella; Kirschsteiniothelia over Dendryphiopsis; Lecanosticta over Eruptio; Paranectriella over Araneomyces; Phaeosphaeria over Phaeoseptoria; Phyllosticta over Guignardia; Podonectria over Tetracrium; Polythrincium over Cymadothea; Prosthemium over Pleomassaria; Ramularia over Mycosphaerella; Sphaerellopsis over Eudarluca; Sphaeropsis over Phaeobotryosphaeria; Stemphylium over Pleospora; Teratosphaeria over Kirramyces and Colletogloeopsis; Tetraploa over Tetraplosphaeria; Venturia over Fusicladium and Pollaccia; and Zeloasperisporium over Neomicrothyrium. Twenty new combinations are made: Acrogenospora carmichaeliana (Berk.) Rossman & Crous, Alternaria scrophulariae (Desm.) Rossman & Crous, Pyrenophora catenaria (Drechsler) Rossman & K.D. Hyde, P. dematioidea (Bubák & Wróbl.) Rossman & K.D. Hyde, P. fugax (Wallr.) Rossman & K.D. Hyde, P. nobleae (McKenzie & D. Matthews) Rossman & K.D. Hyde, P. triseptata (Drechsler) Rossman & K.D. Hyde, Schizothyrium cryptogamum (Batzer & Crous) Crous & Batzer, S. cylindricum (G.Y. Sun et al.) Crous & Batzer, S. emperorae (G.Y. Sun & L. Gao) Crous & Batzer, S. inaequale (G.Y. Sun & L. Gao) Crous & Batzer, S. musae (G.Y. Sun & L. Gao) Crous & Batzer, S. qianense (G.Y. Sun & Y.Q. Ma) Crous & Batzer, S. tardecrescens (Batzer & Crous) Crous & Batzer, S. wisconsinense (Batzer & Crous) Crous & Batzer, Teratosphaeria epicoccoides (Cooke & Massee) Rossman & W.C. Allen, Venturia catenospora (Butin) Rossman & Crous, V. convolvularum (Ondrej) Rossman & Crous, V. oleaginea (Castagne) Rossman & Crous, and V. phillyreae (Nicolas & Aggéry) Rossman & Crous, combs. nov. Three replacement names are also proposed: Pyrenophora grahamii Rossman & K.D. Hyde, Schizothyrium sunii Crous & Batzer, and Venturia barriae Rossman & Crous noms. nov.

Naming and outline of Dothideomycetes-2014 including proposals for the protection or suppression of generic names.

Article 59.1, of the International Code of Nomenclature for Algae, Fungi, and Plants (ICN; Melbourne Code), which addresses the nomenclature of pleomorphic fungi, became effective from 30 July 2011. Since that date, each fungal species can have one nomenclaturally correct name in a particular classification. All other previously used names for this species will be considered as synonyms. The older generic epithet takes priority over the younger name. Any widely used younger names proposed for use, must comply with Art. 57.2 and their usage should be approved by the Nomenclature Committee for Fungi (NCF). In this paper, we list all genera currently accepted by us in Dothideomycetes (belonging to 23 orders and 110 families), including pleomorphic and nonpleomorphic genera. In the case of pleomorphic genera, we follow the rulings of the current ICN and propose single generic names for future usage. The taxonomic placements of 1261 genera are listed as an outline. Protected names and suppressed names for 34 pleomorphic genera are listed separately. Notes and justifications are provided for possible proposed names after the list of genera. Notes are also provided on recent advances in our understanding of asexual and sexual morph linkages in Dothideomycetes. A phylogenetic tree based on four gene analyses supported 23 orders and 75 families, while 35 families still lack molecular data.