High Galacto-Oligosaccharide Production and a Structural Model for Transgalactosylation of β-Galactosidase II from .

The transgalactosylase activity of β-galactosidase produces galacto-oligosaccharides (GOSs) with prebiotic effects similar to those of major oligosaccharides in human milk. β-Galactosidases from ATCC 31382 are important enzymes in industrial-scale GOS production. Here, we show the high GOS yield of β-galactosidase II from (β-Gal-II, Lactazyme-B), compared to other commercial enzymes.

The putative CH transcription factor RocA is a novel regulator of development and secondary metabolism in Aspergillus nidulans.

Multiple transcriptional regulators play important roles in the coordination of developmental processes, including asexual and sexual development, and secondary metabolism in the filamentous fungus Aspergillus nidulans. In the present study, we characterized a novel putative CH-type transcription factor (TF), RocA, in relation to development and secondary metabolism. Deletion of rocA increased conidiation and caused defective sexual development.

The NADP-dependent glutamate dehydrogenase Gdh1 is subjected to glucose starvation-induced reversible aggregation that affects stress resistance in yeast.

The yeast Saccharomyces cerevisiae has two isoforms of NADP-dependent glutamate dehydrogenase (Gdh1 and Gdh3) that catalyze the synthesis of glutamate from α-ketoglutarate and NH. In the present study, we confirmed that Gdh3, but not Gdh1, mainly contributes to the oxidative stress resistance of stationary-phase cells and found evidence suggesting that the insignificance of Gdh1 to stress resistance is possibly resulted from conditional and reversible aggregation of Gdh1 into punctuate foci initiated in parallel with post-diauxic growth. Altered localization to the mitochondria or peroxisomes prevented Gdh1, which was originally localized in the cytoplasm, from stationary phase-specific aggregation, suggesting that some cytosolic factors are involved in the process of Gdh1 aggregation.

Quantitative Proteomic Analysis of 2D and 3D Cultured Colorectal Cancer Cells: Profiling of Tankyrase Inhibitor XAV939-Induced Proteome.

Recently there has been a growing interest in three-dimensional (3D) cell culture systems for drug discovery and development. These 3D culture systems better represent the in vivo cellular environment compared to two-dimensional (2D) cell culture, thereby providing more physiologically reliable information on drug screening and testing. Here we present the quantitative profiling of a drug-induced proteome in 2D- and 3D-cultured colorectal cancer SW480 cells using 2D nanoflow liquid chromatography-tandem mass spectrometry (2D-nLC-MS/MS) integrated with isobaric tags for relative and absolute quantitation (iTRAQ).

Differential Control of Asexual Development and Sterigmatocystin Biosynthesis by a Novel Regulator in Aspergillus nidulans.

The filamentous fungus Aspergillus nidulans primarily reproduces by forming asexual spores called conidia and produces the mycotoxin sterigmatocystin (ST), the penultimate precursor of aflatoxins. It has been known that asexual development and ST production are tightly co-regulated by various regulatory inputs. Here, we report that the novel regulator AslA with a CH domain oppositely regulates development and ST biosynthesis.

Negative regulation of the vacuole-mediated resistance to K(+) stress by a novel C2H2 zinc finger transcription factor encoded by aslA in Aspergillus nidulans.

In fungi and plants, vacuoles function as a storage and sequestration vessel for a wide variety of ions and are responsible for cytosolic ion homeostasis and responses to ionic shock. In the filamentous fungus Aspergillus nidulans, however, little is known about the molecular genetic mechanisms of vacuolar biogenesis and function. In the present study, we analyzed the function of the aslA gene (AN5583) encoding a novel C2H2-type zinc finger transcription factor (TF) in relation to K(+) stress resistance, vacuolar morphology, and vacuolar transporters.

Respiratory syncytial virus infection disrupts monolayer integrity and function in cystic fibrosis airway cells.

Background: Respiratory Syncytial Virus (RSV) infection is a common contributor to pulmonary symptoms in children with cystic fibrosis (CF). Here we examined RSV infection in immortalized bronchial epithelial cells (CFBE41o-) expressing wild-type (wt) or F508del cystic fibrosis transmembrane conductance regulator (CFTR), for monolayer integrity and RSV replication.

Methods: CFBE41o- monolayers expressing wt or F508del CFTR were grown on permeable supports and inoculated with RSV A2 strain.

Mutational biosynthesis of tacrolimus analogues by fkbO deletion mutant of Streptomyces sp. KCTC 11604BP.

Tacrolimus (FK506) is an important macrocyclic polyketide showing antifungal and immunosuppressive activities, as well as neuroregenerative properties. Tacrolimus biosynthetic machinery should incorporate the shikimate-derived 4,5-dihydroxycyclohex-1-enecarboxylic acid (DHCHC) as a biosynthetic starter unit into the biosynthetic line of tacrolimus. fkbO is a homologue of rapK encoding chorismatase related to the biosynthesis of starter unit DHCHC from chorismate in the rapamycin biosynthetic gene cluster.

Detection and genotyping of vancomycin-resistant Enterococcus spp. by multiplex polymerase chain reaction in Korean aquatic environmental samples.

The distribution characteristics of Enterococcus spp., which are indicators of fecal pollution, were investigated at 33 sites within the 3 major water systems of Korea. Enterococci were detected at concentrations ranging from 1 to 37 CFU/100mL in 41 of 132 samples (31.

Involvement of GDH3-encoded NADP+-dependent glutamate dehydrogenase in yeast cell resistance to stress-induced apoptosis in stationary phase cells.

Glutamate metabolism is linked to a number of fundamental metabolic pathways such as amino acid metabolism, the TCA cycle, and glutathione (GSH) synthesis. In the yeast Saccharomyces cerevisiae, glutamate is synthesized from α-ketoglutarate by two NADP(+)-dependent glutamate dehydrogenases (NADP-GDH) encoded by GDH1 and GDH3. Here, we report the relationship between the function of the NADP-GDH and stress-induced apoptosis.

The fission yeast GATA factor, Gaf1, modulates sexual development via direct down-regulation of ste11+ expression in response to nitrogen starvation.

Gaf1 is the first GATA family zinc-finger transcription factor identified in Schizosaccharomyces pombe. Here, we report that Gaf1 functions as a negatively acting transcription factor of ste11(+), delaying the entrance of cells exposed to transient nitrogen starvation into the meiotic cycle. gaf1Δ strains exhibited accelerated G(1)-arrest upon nitrogen starvation.

TCA cycle-independent acetate metabolism via the glyoxylate cycle in Saccharomyces cerevisiae.

In Saccharomyces cerevisiae, the accepted theory is that due to TCA cycle dysfunction, the Δcit1 mutant lacking the mitochondrial enzyme citrate synthase (Cit1) cannot grow on acetate, regardless of the presence of the peroxisomal isoenzyme (Cit2). In this study, we re-evaluated the roles of Cit1 and Cit2 in acetate utilization and examined the pathway of acetate metabolism by analysing mutants defective in TCA or glyoxylate cycle enzymes. Although Δcit1 cells showed significantly reduced growth on rich acetate medium (YPA), they exhibited growth similar to Δcit2 and the wild-type cells on minimal acetate medium (YNBA).

Regioselective deglycosylation of onion quercetin glucosides by Saccharomyces cerevisiae.

Bioconversion of quercetin glucosides using four generally recognized as safe (GRAS) organisms (Aspergillus oryzae, Bacillus subtilis, Lactobacillus plantarum, and Saccharomyces cerevisiae) was evaluated by measuring changes in the levels of quercetin compounds of onion. Of the four organisms, S. cerevisiae increased the content of quercetin-3-O-β-D-glucoside (III; isoquercitrin) and quercetin (IV), whereas decreasing quercetin-3,4'-O-β-D-glucoside (I) and quercetin-4'-O-β-D-glucoside (II).

A new fibrinolytic enzyme (55 kDa) from Allium tuberosum: purification, characterization, and comparison.

Chives have been used both as food and as medicine. Previously, two fibrinolytic enzymes, ATFE-I (90 kDa) and ATFE-II (55 kDa), were identified in chives (Allium tuberosum), a perennial herb. In the present work, ATFE-II was purified by ion-exchange chromatography followed by gel filtration.

Differential expression of citA gene encoding the mitochondrial citrate synthase of Aspergillus nidulans in response to developmental status and carbon sources.

As an extension of our previous studies on the mitochondrial citrate synthase of Aspergillus nidulans and cloning of its coding gene (citA), we analyzed differential expression of citA in response to the progress of development and change of carbon source. The cDNA consisted of 1,700 nucleotides and was predicted to encode a 474-amino acid protein. By comparing the cDNA sequence with the corresponding genomic sequence, we confirmed that citA gene contains 7 introns and that its transcription starts at position -26 (26-nucleotide upstream from the initiation codon).

Remodeling of global transcription patterns of Cryptococcus neoformans genes mediated by the stress-activated HOG signaling pathways.

The ability to sense and adapt to a hostile host environment is a crucial element for virulence of pathogenic fungi, including Cryptococcus neoformans. These cellular responses are evoked by diverse signaling cascades, including the stress-activated HOG pathway. Despite previous analysis of central components of the HOG pathway, its downstream signaling network is poorly characterized in C.

Purification and characterization of a novel thermoacid-stable fibrinolytic enzyme from Staphylococcus sp. strain AJ isolated from Korean salt-fermented Anchovy-joet.

A novel fibrinolytic enzyme (AJ) was purified from Staphylococcus sp. strain AJ screened from Korean salt-fermented Anchovy-jeot. Relative molecular weight of AJ was determined as 26 kDa by using SDS-PAGE and fibrin zymography.

Genome-wide identification of haploinsufficiency in fission yeast.

Abnormal phenotypes resulting from haploinsufficiency (HI) are due to the loss of one allele. Recent studies in budding yeast have shown that HI originates from insufficient protein levels or from a stoichiometric imbalance between subunits of protein complexes. In humans, however, HI often involves transcription factors.

Hepatitis B virus X protein enhances NFkappaB activity through cooperating with VBP1.

Hepatitis B virus X protein (HBx) is essential for hepatitis B virus infection and exerts a pleiotropic effect on various cellular machineries. HBx has been also demonstrated as an indirect transcriptional transactivator of various different viral and cellular promoters. In addition, HBx is involved in the development of various liver diseases including hepatocellular carcinoma.

Yeast cells lacking the CIT1-encoded mitochondrial citrate synthase are hypersusceptible to heat- or aging-induced apoptosis.

In Saccharomyces cerevisiae, the initial reaction of the tricarboxylic acid cycle is catalyzed by the mitochondrial citrate synthase Cit1. The function of Cit1 has previously been studied mainly in terms of acetate utilization and metabolon construction. Here, we report the relationship between the function of Cit1 and apoptosis.

Mutational and functional analysis of the cryptic N-terminal targeting signal for both mitochondria and peroxisomes in yeast peroxisomal citrate synthase Cit2p.

We previously found that the peroxisomal citrate synthase of Saccharomyces cerevisiae, Cit2p, contains a cryptic targeting signal for both peroxisomes (PTS) and mitochondria (MTS) within its 20-amino acid N-terminal segment [Lee et al. (2000) J. Biochem.

A method for direct application of human plasmin on a dithiothreitol-containing agarose stacking gel system.

A new simplified procedure for identifying human plasmin was developed using a DTT copolymerized agarose stacking gel (ASG) system. Agarose (1 %) was used for the stacking gel because DTT inhibits the polymerization of acrylamide. Human plasmin showed the lowest activity at pH 9.

IFN-gamma regulates the expression of B7-H1 in dermal fibroblast cells.

Background: Programmed cell death ligand 1 (B7-H1) was recently cloned in antigen presenting cells (APCs) and represents a third member of the B7 family. Thus, B7-H1 may be a novel target for clinical intervention in human inflammatory disease.

Objective: The aim of this study is to investigate the signal transduction mechanism and transcriptional regulation of B7-H1 expression in human dermal fibroblasts.