Search

A comparative proteome analysis of extracellular proteins is carried out under solid-state and submerged culture conditions and protein secretion profiles are determined. A Northern analysis of seven genes from the four groups have indicated that the secretion of alpha-amylase (TAA) and beta-glucosidase (Bgl) are regulated by trapping these proteins in the cell wall in submerged culture and that secretion of glucoamylase A (GlaA) and xylanase G2 (XynG2) are regulated at the posttranscriptional level in the solid-state culture.

Author(s): Masayuki Machida (corresponding author) [1]; Kiyoshi Asai [2]; Motoaki Sano [1]; Toshihiro Tanaka [3]; Toshitaka Kumagai [2]; Goro Terai [2, 20]; Ken-Ichi Kusumoto [4]; Toshihide Arima [5]; Osamu Akita [...]

Manganese complexes of enantiomerically strapped porphyrins bearing two chemically distinct, diastereotopic faces successfully mediated the asymmetric epoxidation of prochiral olefins. The catalysts were obtained from enantiotopic porphyrins containing either p-xylylene, m-xylylene or dodecamethylene straps. Reactions involving the chiral metalloporphyrin catalysts procceded with good enantioselectivity. Additionally, the presence of imidazole affected the enantioselectivity of the catalytic process.

The article presents a study on the gene regulation of kojic acid (KA) synthesis in Aspergillus oryzae. The study used real-time polymerase chain reaction (PCR) to confirm the recovery of KA in the fermentation using LaeA complement strain which was lost during the laeA disruption strain. The results indicate that KA biosynthesis are being regulated by LaeA.

Aspergillus luchuensis is a kuro (black) koji fungus that has been used as a starch degrader for the awamori- and shochu-making industries in Japan. In this study, we investigated the effect of ion beam irradiation on A. luchuensis RIB2601 and obtained a high starch-degrading mutant strain U1. Strain U1 showed reduced growth rate, whereas it showed higher α-amylase, glucoamylase, and α-glucosidase activities on a mycelial mass basis than the wild type (wt) strain both on agar plates and in rice koji. In addition, strain U1 showed higher N-acetylglucosamine content in the cell wall and higher sensitivity to calcofluor white, suggesting a deficiency in cell wall composition. Interestingly, produced protein showed higher expression of acid-labile α-amylase (AmyA) and glucoamylase (GlaA) in strain U1, although real-time RT-PCR indicated no significant change in the transcription of the amyA or glaA gene. These results suggested that the high amylolytic activity of strain U1 is attributable to a high AmyA and GlaA production level, but the elevated production is not due to transcriptional regulation of the corresponding genes. Furthermore, RNA-seq analysis indicated that strain U1 shows transcriptional changes in at least 604 genes related to oxidation-reduction, transport, and glucosamine-containing compound metabolic processes, which may be involved in the deficient cell wall composition of strain U1.

Aspergillus fumigatus is the most common airborne pathogen causing fatal mycoses in immunocompromised patients. During the first 8 hours of development A. fumigatus conidia break dormancy, expand isotopically, establish an axis of polarity, and begin to extend germ tubes in a polar manner. The transition from isotropic to polar growth is critical for tissue invasion and pathogenesis. In the current work, we used two-color microarrays to examine the A. fumigatus transcriptome during early development, focusing on the isotropic to polar switch. The most highly regulated transcripts in the isotropic to polar switch did not include known polarity genes. Transcripts encoding the Cdc42 module, polarisome components, and septins, known to be critical players in polarity, showed relatively steady levels during the isotropic to polar switch. Indeed, these transcripts were present in dormant conidia, and their levels changed little from dormancy through germ tube emergence. Not only did the isotropic to polar switch show little change in the expression of key polarity genes of the Cdc42 module, polarisome, and septins, it also showed the lowest overall levels of both up- and downregulation in early development., (© The Author 2016. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

A gene of exo-1,3-beta-D-glucanase (exgS) was cloned from a koji mold, Aspergillus saitoi, genomic DNA using PCR. The exgS has an ORF comprising 2832 bp, which contains one intron of 45 bp, and encodes 945 amino acids. The deduced amino acid sequences showed that the ExgS has a non-homologous linker region consisting of 180 amino acids, which encompassed highly conserved regions observed in Exg homologues from filamentous fungi. A recombinant protein (ExgS) has been recovered from the cultural filtrate of an Aspergillus oryzae strain that carried an expression vector containing full length of the exgS. The N-terminal amino acid sequences of the recombinant exo-1,3-beta-D-glucanase (ExgS) were identical to that of native ExgS from A. saitoi.