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Decomposition of organic matters in volcanic soils (ando soils) is generally slowed by sorption onto short-range-order minerals, while decomposition of non-charged substrates such as cellulose and glucose is hypothesized to be promoted by high microbial biomass and nitrogen availability, irrespective of short-range-order minerals. To analyze factors regulating decomposition activities of cellulose and glucose, we measured the decomposition rates of cellulose filter papers and the mineralization rates of 14C-labeled glucose in five volcanic soils in Japan. Glucose mineralization activities increased with increasing microbial biomass C and N, while cellulose decomposition activities (standardized with cumulative temperature) were not related to microbial biomass C or N. Cellulose decomposition activities increased with increasing ratio of soil available N relative to microbial biomass N (microbial N availability), while they decreased with decreasing soil pH and with increasing fungal activities. Soils with relatively high soil pH and microbial N availability exhibit the relatively high potentials of cellulose decomposition. Because cellulose decomposition, rather than glucose mineralization, is a rate-limiting step, soil pH and microbial N availability, rather than microbial biomass, could primarily regulate decomposition rates of cellulose and glucose in volcanic soils. [ABSTRACT FROM AUTHOR]

The cellulose-degrading fungus strain Talaromyces cellulolyticus (formerly known as Acremonium cellulolyticus) Y-94, which was isolated in 1982 from soil in Japan, and strain S6-25, a derivative of Y-94 with higher cellulase productivity, are fungi that exhibit promise as alternatives to Trichoderma reesei for the industrial production of cellulase. MALDI-TOF MS analysis of the T. cellulolyticus Y-94 protein secretome demonstrated that strain Y-94 expressed and secreted a broad spectrum of proteins for the degradation of hemicellulose, starch, or pectin; these proteins include 2 types of α-L-arabinofuranosidases, 2 types of putative glucoamylases, Streptomyces laminarinase-like protein, mutanase, α-amylase, polysaccharide lyase family 6/pectate lyase 3, and β-N-acetylhexosaminidase. The cellulase system of strain S6-25 had the same cellobiohydrolases (Cel6A and Cel7A), β-glucosidase (Bgl3A), xylanase (Xyl10A), and endoglucanase (Cel5A) as strain CF-2612, another derivative of Y-94. However, instead of Cel7B, S6-25 cells expressed another endoglucanase (Cel5C). Two cellobiohydrolases, Cel7A and Cel6A, represented approximately 60% (wt/wt) of the proteins secreted by the strain and were the main enzymes of the cellulase complex. The increase in cellulase complex activity in the S6-25 strain compared with Y-94 may be explained, at least partly, by the presence of an additional copy of the cel7A gene in the cellular genome, which was confirmed by RT-qPCR analysis. [ABSTRACT FROM AUTHOR]

The ascomycete Trichoderma reesei is known to produce a variety of cellulases and hemicellulases and the hyper-cellulolytic mutants of this fungus are useful as industrial cellulase producers. In Japan, PC-3-7, derived from the early mutant QM9414, is well-known as a cellulase hyperproducing mutant. In addition to the productivity of enzymes, the composition of secreted enzymes greatly influences biomass saccharification. Therefore, we evaluated the cellulase productivity of T. reesei mutants in Japan at different pH as a factor influencing enzyme production. At higher pH values, QM9414 exhibited reduced cellulase productivity whereas PC-3-7 maintained high cellulase productivity and gene expression at the transcriptional level. The gene encoding the pH-responsive transcription factor PACI did not mutate in PC-3-7, and its expression pattern against different pH conditions was similar between QM9414 and PC-3-7. Furthermore, the deletion of pac1 encoding PACI caused different expression patterns of cellulase genes between QM9414 and PC-3-7. Therefore, we suggest that T. reesei possesses a pH-responsive cellulase production mechanism that is different from the PACI-related mechanism. Finally, we identified that N-25, a strain developed at an early stage of mutant development acquired cellulase productivity at a higher pH. In this investigation, we also found and tested candidate genes possibly affecting pH response using comparative genome analysis. [ABSTRACT FROM AUTHOR]

The land crabs, Chiromantes haematocheir (Akate-gani) and Chiromantes dehaani (Kurobenkei-gani) inhabit seaside forests in Japan. The crabs mainly consume plant material and its detritus. Therefore, they are expected to possess the ability to degrade the major components of biomass, cellulose and lignin in order to digest plant materials. In this study, we analyzed biomass-degrading activities of the land crabs, especially guaiacol oxidation activity, which seems to be related to lignin degradation. Cellulase activity was detected from almost all gut samples including the stomach, midgut gland and intestine of all dissected crabs. Conversely, high guaiacol oxidation activity was detected in the midgut gland of all C. dehaani and several female C. haematocheir crabs. This is consistent with a previous study showing that female crabs were more herbivorous than male crabs were and observation that C. dehaani crabs are more herbivorous than C. haematocheir. Guaiacol oxidation activity might play an important role in the herbivorous behavior of land crabs. [ABSTRACT FROM AUTHOR]

Abstract: This study aimed to clarify the relationship between cellulase activity and habitat segregation for two dotillid crabs – Scopimera globosa and Ilyoplax pusilla – on the marsh-dominated Tanakagawa tidal flat in central Japan. Both species are deposit feeders, and represent the dominant crab species in the study area. S. globosa was found to occur within sandy sediment habitats on the tidal flat, while I. pusilla occurred in both muddy sediment on the tidal flat and salt marsh habitats. This study was the first to detect cellulase activity in dotillid crabs. Cellulase activity was detected for both species; I. pusilla was found to exhibit significantly higher activity than S. globosa. Organic matter content, which is known to have a strong positive correlation with the cellulose content of sediments in estuarine areas, was higher in the sediments of muddy and salt marsh habitats compared with those in sandy habitats. Our findings indicate a close relationship between the habitat segregation of these two crabs and their cellulase activity. Given that cellulose is abundant in refractory organic materials and is a major component of food resources in tidal flat sediments, it is likely that these two crab species, especially I. pusilla, would play an important role in material cycling in tidal flat and estuarine areas. [Copyright &y& Elsevier]

The article discusses isolation and characterization of cellulolytic microbes in the soil of the Yanbaru which is a subtropical forest with an endemic biota on Okinawa Island, Japan. It reports that bacterial and fungal isolates that belongs different bacterial genera were characterized on the basis of phylogenetic analysis. It mentions that the isolates possess cellulose and xylanose degrading properties.

To reduce the volume of seaweed wastes and extract polysaccharides, seaweed-degrading bacteria were isolated from drifting macroalgae harvested along the coast of Toyama Bay, Japan. Sixty-four bacterial isolates were capable of degrading 'Wakame' ( Undaria pinnatifida) thallus fragments into single cell detritus (SCD) particles. Amongst these, strain 6532A was the most active degrader of thallus fragments, and was capable of degrading thallus fragments to SCD particles within a day. Although the sequence similarity of the 16S rRNA gene of strain 6532A was 100% similar to that of Microbulbifer elongatus JAMB-A7, several distinct differences were observed between strains, including motility, morphology, and utilization of d-arabinose and gelatin. Consequently, strain 6532A was classified as a new Microbulbifer strain, and was designated Microbulbifer sp. 6532A. Strain 6532A was capable of degrading both alginate and cellulose in the culture medium, zymogram analysis of which revealed the presence of multiple alginate lyases and cellulases. To the best of our knowledge, this is the first study to directly demonstrate the existence of these enzymes in Microbulbifer species. Shotgun cloning and sequencing of the alginate lyase gene in 6532A revealed a 1,074-bp open reading frame, which was designated algMsp. The reading frame encoded a PL family seven enzyme composed of 358 amino acids (38,181 Da). With a similarity of 74.2%, the deduced amino acid sequence was most similar to a Saccharophagus enzyme ( alg 7C). These findings suggest that algMsp in strain 6532A is a novel alginate lyase gene. [ABSTRACT FROM AUTHOR]

To validate the involvement of meiobenthos in cellulose breakdown in wetlands, meiobenthos were collected from sediments of Lake Furen and the Biwase River in Hokkaido Prefecture, the Kako River in Hyogo Prefecture, and the Chinai River in Shiga Prefecture. Cellulase activities of the meiobenthos were measured by cellulose zymographic analysis using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) gels containing 0.5% carboxymethyl cellulose. The results showed that most of the Turbellaria, Nematoda, Harpacticoida, and Oligochaeta species exhibited cellulase activity. The molecular sizes of the cellulase-active bands of the sediments in Lake Furen, the Biwase River, and the Chinai River coincided with those of meiobenthos. The findings suggest that meiobenthos might play a major function in cellulose breakdown in these wetlands. This paper is the first to report cellulase activity in meiobenthos and that they are possibly involved in the breakdown of cellulose in wetlands. [ABSTRACT FROM AUTHOR]

Abstract: Silage production from rice straw and whole-plant forage paddy rice is increasing in Japan because of decrease in rice consumption. One potential use for this silage is bioethanol production. In this study, we analyzed the effectiveness of three different commercially available cellulases at saccharification of sun-dried rice straw, ensiled rice straw, and rice whole-crop silage (WCS). Furthermore, the ethanol productivity of the simultaneous saccharification and ethanol fermentation process (SSF) from the same plant substrates was analyzed. Among the three kinds of cellulases tested (Novozymes NS50013, Genencor GC220, and Acremonium cellulase), Acremonium cellulase showed the highest ethanol production for the three plant substrates, and the WCS produced the highest ethanol level. Analysis of the enzymatic degradation activity of the cellulases revealed that Acremonium cellulase contained remarkably high glucoamylase and pectinase side activities relative to the other cellulase preparations. The addition of glucoamylase and pectinase to the other two cellulases significantly increased ethanol productivity to levels observed for the Acremonium cellulase preparation, which showed little enhanced performance with the addition of the same enzymes. Finally, we tested whether milling and sterilization had an effect on ethanol production and found that sterilized silage produced higher ethanol levels but that the milling process had no significant effect. These results show that (i) silage made from whole-plant rice can be used for bioethanol production and (ii) the proper selection and combination of commercially available enzymes can make SSF more cost efficient by removing the need for a pre-treatment step. [Copyright &y& Elsevier]

Corbicula japonica is a typical brackish water bivalve species belonging to the order Veneroida, and it is the most important inland fishery resource in Japan. Corbicula japonica has been suggested to assimilate organic matter from terrestrial plants, unlike Ruditapes phiippinarum and Mactra veneriformis, which selectively assimilate organic matter of marine origin. This led us to hypothesize that C. japonica, despite being a suspension feeder, could assimilate cellulosic materials derived from terrestrial plants. In the present study, we measured cellulase and hemicellulase activities in the crystalline styles of C. japonica and other commercially important Veneroida bivalve species in Japan: Ruditapes philippinarum, Meretrix lamarckii and Meretrix lusoria. Corbicula japonica demonstrated notably higher cellulase, xylanase and β-mannanase activities than the other marine bivalves, suggesting that this species possesses a far greater biochemical capacity to break down the structural polysaccharides of plant cell walls than the other species. In contrast, the β-1 ,3-glucanase and pectinase activities of C. japonica were similar to or even lower than those of the others. This is possibly due to the presence of these polysaccharides in the cell walls of diatoms, a principal food of most marine bivalves. Although direct evidence is lacking, the high cellulase, xylanase and β-mannanase activities of C. japonica may result from adaptation to an upstream estuarine environment where phytoplankton and diatoms are scarce, but plant-derived substances are abundant. [ABSTRACT FROM AUTHOR]

Cellulose is the most naturally abundant biopolymer on the Earth and a low- cost energy source. It consists of a linear homopolysaccharide composed by beta-D-glucopyranose units linked by beta-1,4 glycosidic bonds. Cellulases hydrolyze beta-1,4 linkages in cellulose chains. In nature, complete cellulose hydrolysis is mediated by a combination of three main types of cellulases: endoglucanases, exoglucanases (including cellobiohydrolases), and beta- glucosidase. Cellulases play a major role in industries such as paper, textile, detergent, food, and biorefinery. Halophilic microorganisms are excellent sources for salt stable enzymes that can effectively withstand and react under extreme salinity conditions. For instance, they play an essential role in various fermentation processes that occur in the presence of salt. Recently, we isolated 6 moderate halophilic, CMC-degrading strains from non-saline garden soil samples in Japan. After incubated at 37°C for 3 weeks, they produced clearance zone around colonies on agar plates containing 0.2% carboxymethyl cellulose (CMC), when stained with 0.1 % Congo red on the agar plates. Based on the 16S rRNA gene sequencing the isolates were found as closely related to Piscibacillus, Halobacillus, Thalassobacillus, Lentibacillus, and Virgibacillus, respectively. The activity profile of their enzymes showed the optimum residual activity at temperature 50 °C. The cellulase activity was found to be stabilized in the salt range of 6-15% and thus evident for halophilic nature of the enzyme. [ABSTRACT FROM AUTHOR]