Isolation of a new laccase isoform from the white-rot fungiPycnoporus cinnabarinusstrain ss3

2000 ◽  
Vol 46 (8) ◽  
pp. 759-763 ◽  
Author(s):  
Ludovic Otterbein ◽  
Eric Record ◽  
David Chereau ◽  
Isabelle Herpoël ◽  
Marcel Asther ◽  
...  

Two extracellular laccase isoforms (Lac I and Lac II) produced by the white-rot fungus Pycnoporus cinnabarinus from the monokaryotic strain ss3 were purified from ferulic-acid-induced liquid culture medium using ammonium sulphate precipitation, followed by anion-exchange chromatography on a Mono Q column. Strain ss3 is the first generation of the parental strain P. cinnabarinus I-937. The new isolated isoform, Lac II, consists of an 86 000 molecular weight protein as determined by SDS polyacrylamide gel electrophoresis. The N-terminal amino acid sequences of both isoforms were determined, and compared to known laccase protein sequences of other organisms.Key words: oxydo-reductase, filamentous fungi, purification.

Holzforschung ◽  
2011 ◽  
Vol 65 (5) ◽  
Author(s):  
Christian Lehringer ◽  
Bodo Saake ◽  
Vjekoslav Živković ◽  
Klaus Richter ◽  
Holger Militz

AbstractThe biotechnological application of the white rot fungusPhysisporinus vitreusnamed “bioincising” is currently being investigated for permeability improvement of Norway spruce (Picea abies(L.) Karst.) wood. During short-term (<9 weeks) incubation, fungal activity induces degradation of pit membranes and a simultaneous alteration of the tracheid cell wall structure. In Part 1 of this article series, the occurrence of selective delignification and simultaneous degradation was shown by UV-microspectrophotometry (UMSP). Moreover, significant reduction of Brinell hardness was recorded after 7 and 9 weeks incubation. For a better understanding of the chemical alterations in the wood constituents and the corresponding changes of mechanical properties due to fungal activity, we applied microtensile tests on thin strips that were prepared from the surface of incubated Norway spruce wood. Indications for the occurrence of selective delignification and simultaneous degradation were evident. Determination of lignin content and carbohydrate analysis by borate anion exchange chromatography confirmed the results. The present study verifies the findings from Part 1 of this article series and from previously conducted microscopic investigations. Now, the degradation characteristics ofP. vitreusare established and the bioincising process can be further optimized with higher reliability.


Toxins ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 476 ◽  
Author(s):  
Zhimin Zhou ◽  
Renkuan Li ◽  
Tzi Bun Ng ◽  
Yunyun Lai ◽  
Jie Yang ◽  
...  

Aflatoxin B1 (AFB1) is a known toxic human carcinogen and can be detoxified by laccases, which are multicopper oxidases that convert several environmental pollutants and toxins. In this study, a new laccase that could catalyze AFB1 degradation was purified and identified from the white-rot fungus Cerrena unicolor 6884. The laccase was purified using (NH4)2SO4 precipitation and anion exchange chromatography, and then identified as Lac 2 through zymogram and UHPLC-MS/MS based on the Illumina transcriptome analysis of C. unicolor 6884. Six putative laccase protein sequences were obtained via functional annotation. The lac 2 cDNA encoding a full-length protein of 512 amino acids was cloned and sequenced to expand the fungus laccase gene library for AFB1 detoxification. AFB1 degradation by Lac 2 was conducted in vitro at pH 7.0 and 45 °C for 24 h. The half-life of AFB1 degradation catalyzed by Lac 2 was 5.16 h. Acetosyringone (AS), Syrinagaldehyde (SA) and [2,2′ -azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid)] (ABTS) at 1 mM concentration seemed to be similar mediators for strongly enhancing AFB1 degradation by Lac 2. The product of AFB1 degradation catalyzed by Lac 2 was traced and identified to be Aflatoxin Q1 (AFQ1) based on mass spectrometry data. These findings are promising for a possible application of Lac 2 as a new aflatoxin oxidase in degrading AFB1 present in food and feeds.


1999 ◽  
Vol 65 (2) ◽  
pp. 389-395 ◽  
Author(s):  
Ulrike Temp ◽  
Claudia Eggert

ABSTRACT When glucose is the carbon source, the white rot fungusPycnoporus cinnabarinus produces a characteristic red pigment, cinnabarinic acid, which is formed by laccase-catalyzed oxidation of the precursor 3-hydroxyanthranilic acid. When P. cinnabarinus was grown on media containing cellobiose or cellulose as the carbon source, the amount of cinnabarinic acid that accumulated was reduced or, in the case of cellulose, no cinnabarinic acid accumulated. Cellobiose-dependent quinone reducing enzymes, the cellobiose dehydrogenases (CDHs), inhibited the redox interaction between laccase and 3-hydroxyanthranilic acid. Two distinct proteins were purified from cellulose-grown cultures of P. cinnabarinus; these proteins were designated CDH I and CDH II. CDH I and CDH II were both monomeric proteins and had apparent molecular weights of about 81,000 and 101,000, respectively, as determined by both gel filtration and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The pI values were approximately 5.9 for CDH I and 3.8 for CDH II. Both CDHs used several known CDH substrates as electron acceptors and specifically adsorbed to cellulose. Only CDH II could reduce cytochrome c. The optimum pH values for CDH I and CDH II were 5.5 and 4.5, respectively. In in vitro experiments, both enzymes inhibited laccase-mediated formation of cinnabarinic acid. Oxidation intermediates of 3-hydroxyanthranilic acid served as endogenous electron acceptors for the two CDHs from P. cinnabarinus. These results demonstrated that in the presence of a suitable cellulose-derived electron donor, CDHs can regenerate fungal metabolites oxidized by laccase, and they also supported the hypothesis that CDHs act as links between cellulolytic and ligninolytic pathways.


2010 ◽  
Vol 76 (19) ◽  
pp. 6431-6440 ◽  
Author(s):  
Ingo Morgenstern ◽  
Deborah L. Robertson ◽  
David S. Hibbett

ABSTRACT We report the sequence-based characterization and expression patterns of three manganese peroxidase genes from the white rot fungus and grape vine pathogen Fomitiporia mediterranea (Agaricomycotina, Hymenochaetales), termed Fmmnp1, Fmmnp2, and Fmmnp3. The predicted open reading frames (ORFs) are 1,516-, 1,351-, and 1,345-bp long and are interrupted by seven, four, and four introns, respectively. The deduced amino acid sequences encode manganese peroxidases (EC 1.11.1.13) containing 371, 369, and 371 residues, respectively, and are similar to the manganese peroxidases of the model white rot organism Phanerochaete chrysosporium. The expression of the genes is most likely differentially regulated, as revealed by real-time PCR analysis. Phylogenetic analysis reveals that other members of the order Hymenochaetales harbor mnp genes encoding proteins that are related only distantly to those of F. mediterranea. Furthermore, multiple partial lip- and mnp-like sequences obtained for Pycnoporus cinnabarinus (Agaricomycotina, Polyporales) suggest that lignin degradation by white rot taxa relies heavily on ligninolytic peroxidases and is not efficiently achieved by laccases only.


1980 ◽  
Vol 33 (3) ◽  
pp. 279 ◽  
Author(s):  
RN Murdoch ◽  
Louise E Buxton ◽  
DJ Kay

An improved procedure for the purification of alkaline phosphatase from about 10 g of day 7 pregnant mouse uterine tissue is described. Following homogenization, the procedure involved solubilization and extraction with 0�8% (v/v) Triton X-lOO and 20% (v/v) n-butanol, ammonium sulfate precipitation, concanavalin A-Sepharose 4B affinity chromatography, DEAE-cellulose anion-exchange chromatography and Sephacryl S200 gel filtration. On subjecting 2162-fold purified enzyme preparations to polyacrylamide-gel electrophoresis, a single band of protein coincident with the zone of enzyme activity and having an apparent molecular weight of 205 OOO� lOOOO was identified. Affinity chromatography yielded the largest increase in purity of any step in the procedure and established the glycoprotein nature of the uterine enzyme.


2004 ◽  
Vol 70 (4) ◽  
pp. 2367-2372 ◽  
Author(s):  
Xiaokun Wang ◽  
Xin Geng ◽  
Yukari Egashira ◽  
Hiroo Sanada

ABSTRACT Dietary ferulic acid (FA), a significant antioxidant substance, is currently the subject of extensive research. FA in cereals exists mainly as feruloylated sugar ester. To release FA from food matrices, it is necessary to cleave ester cross-linking by feruloyl esterase (FAE) (hydroxycinnamoyl esterase; EC 3.1.1.73). In the present study, the FAE from a human typical intestinal bacterium, Lactobacillus acidophilus, was isolated, purified, and characterized for the first time. The enzyme was purified in successive steps including hydrophobic interaction chromatography and anion-exchange chromatography. The purified FAE appeared as a single band in sodium dodecyl sulfate-polyacrylamide gel electrophoresis, with an apparent molecular mass of 36 kDa. It has optimum pH and temperature characteristics (5.6 and 37°C, respectively). The metal ions Cu2+ and Fe3+ (at a concentration of 5 mmol liter−1) inhibited FAE activity by 97.25 and 94.80%, respectively. Under optimum pH and temperature with 5-O-feruloyl-l-arabinofuranose (FAA) as a substrate, the enzyme exhibited a K m of 0.0953 mmol liter−1 and a V max of 86.27 mmol liter−1 min−1 mg−1 of protein. Furthermore, the N-terminal amino acid sequence of the purified FAE was found to be A R V E K P R K V I L V G D G A V G S T. The FAE released FA from O-(5-O-feruloyl-α-l-arabinofuranosyl)-(1→3)-O-β-d-xylopyranosyl-(1→4)-d-xylopyranose (FAXX) and FAA obtained from refined corn bran. Moreover, it released two times more FA from FAXX in the presence of added xylanase.


1984 ◽  
Vol 220 (3) ◽  
pp. 811-818 ◽  
Author(s):  
M P Waalkes ◽  
S B Chernoff ◽  
C D Klaassen

Cadmium-binding proteins in the cytosol of testes from untreated rats were separated by Sephadex G-75 gel filtration. Three major testicular metal-binding proteins (TMBP), or groups of proteins, with relative elution volumes of approx. 1.0 (TMBP-1), 1.7 (TMBP-2) and 2.4 (TMBP-3) were separated. Elution of Zn-binding proteins exhibited a similar pattern. TMBP-3 has previously been thought to be metallothionein (MT), and hence this protein was further characterized and compared with hepatic MT isolated from Cd-treated rats. Estimation of Mr by gel filtration indicated a slight difference between MT (Mr 10000) and TMBP-3 (Mr 8000). Two major forms of MT (MT-I and MT-II) and TMBP-3 (TMBP-3 form I and TMBP-3 form II) were obtained after DEAE-Sephadex A-25 anion-exchange chromatography, with the corresponding subfractions being eluted at similar conductances. Non-denaturing polyacrylamide-gel electrophoresis on 7% acrylamide gels indicated that the subfractions of TMBP-3 had similar mobilities to those of the corresponding subfractions of MT. However, SDS (sodium dodecyl sulphate)/12% (w/v)-polyacrylamide-gel electrophoresis resulted in marked differences in migration of the two corresponding forms of MT and TMBP-3. Co-electrophoresis of MT-II and TMBP-3 form II by SDS/polyacrylamide-gel electrophoresis revealed two distinct proteins. Amino acid analysis indicated much lower content of cysteine in the testicular than in the hepatic proteins. TMBP-3 also contained significant amounts of tyrosine, phenylalanine and histidine, whereas MT did not. U.v.-spectral analysis of TMBP-3 showed a much lower A250/A280 ratio than for MT. Thus this major metal-binding protein in testes, which has been assumed to be MT is, in fact, a quite different protein.


1992 ◽  
Vol 38 (3) ◽  
pp. 203-208 ◽  
Author(s):  
C. Yanze Kontchou ◽  
Roland Blondeau

Biodegradation of soil humic acids by Streptomyces viridosporus ATCC 39115 growing in a mineral salts – glucose medium was demonstrated. This biodegradation accompanies bacterial growth and is, therefore, presumed to be a primary metabolic activity, but humic acids were not used as the sole source of carbon. This bacterial activity was enhanced when cells were shaken and within a pH range of 6.5–8.5. In further experiments, the relative abilities of S. viridosporus to mineralize [14C]melanoidin, used as synthetic humic acid, were also established. In contrast to the white rot fungus Phanerochaete chrysosporium, another microorganism exhibiting humic acid degrading activity at acidic pH, poor extracellular activities were found in culture medium of S. viridosporus, and veratryl alcohol does not result in increased humic acid degradation. In spite of some peroxidase activity measured in culture filtrates and analyzed by polyacrylamide gel electrophoresis, the humic acid degrading system of S. viridosporus, in these experimental conditions, seems to be cell associated. Key words: humic acid biodegradation, melanoidin mineralization, Streptomyces viridosporus, cell-bound humic acids.


2001 ◽  
Vol 354 (1) ◽  
pp. 161-168 ◽  
Author(s):  
Ying-Ming WANG ◽  
Suei-Rong WANG ◽  
Inn-Ho TSAI

The major coagulating fibrinogenase of Deinagkistrdon acutus venom, designated acutobin, was purified by anion-exchange chromatography, gel filtration and reverse-phase HPLC. Approximately 80% of its protein sequence was determined by sequencing the various fragments derived from CNBr cleavage and digestion with endoprotease. Extensive screening of the venom gland cDNA species after amplification by PCR resulted in the isolation of four distinct cDNA clones encoding acutobin and three other serine proteases, designated Dav-PA, Dav-KN and Dav-X. The complete amino acid sequences of these enzymes were deduced from the cDNA sequences. The amino-acid sequence of acutobin contains a single chain of 236 residues including four potential N-glycosylation sites. The purified acutobin (40kDa) contains approx. 30% carbohydrate by weight, which could be partly removed by N-glycanase. The phylogenetic tree of the complete amino acid sequences of 40 serine proteases from 18 species of Crotalinae shows functional clusters reflecting parallel evolution of the three major venom enzyme subtypes: coagulating enzymes, kininogenases and plasminogen activators. The possible structural elements responsible for the functional specificity of each subtype are discussed.


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