Invertase production by Saccharomyces cerevisiae protoplasts immobilized in strontium alginate gel beads.

The invertase productivity of Saccharomyces cerevisiae IFO 0309 protoplasts in a static culture was 35 times (extracellular) and 9 times (extracellular + intracellular) higher than those of cells. When S. cerevisiae protoplasts were immobilized in 1.

Efficient conversion of itaconic acid to (S)-(+)-citramalic acid by Alcaligenes xylosoxydans IL142.

The effective production of (S)-(+)-citramalic acid from itaconic acid with an enantiomeric purity of more than 99.9% was successfully achieved using resting cells of a newly isolated strain, Alcaligenes xylosoxydans IL142. The highest conversion activity was obtained with an itaconic acid concentration of 65.

Production of highly concentrated xylitol by Candida magnoliae under a microaerobic condition maintained by simple fuzzy control.

Microbial production of xylitol from xylose was investigated using Candida magnoliae. In particular, the effect of the oxygenation condition on the xylitol production yield was examined and the significance of maintaining a microaerobic condition was demonstrated. A simple system of fuzzy logic control (FLC) was devised to maintain the microaerobic condition in the xylitol production phase by regulating the proportion of air (air flow rate) supplied to the fermentor.

Synergistic effect of active oxygen species and alginate on chitinase production by Wasabia japonica cells and its application.

The specific chitinase productivity of a Wasabia japonica cell suspension culture under pure oxygen aeration was 3.8 times higher than that of a suspension culture aerated with ordinary air. During aeration with pure oxygen, both oxygen consumption by the cells and the H2O2 concentration in the medium increased.

The alpha-aminoadipate pathway for lysine biosynthesis is widely distributed among Thermus strains.

We previously reported that lysine is synthesized through the alpha-aminoadipate pathway in Thermus thermophilus HB27 (T. Kosuge and T. Hoshino, FEMS Microbiol.

Purification and properties of culture-broth-secreted esterase from the polyurethane degrader Comamonas acidovorans TB-35.

The polyester-polyurethane (PUR)-degrading bacterium Comamonas acidovorans TB-35 produces two kinds of esterases, one cell-bound esterase (PUR esterase) and the other secreted in the culture broth (CBS esterase). In this study, the CBS esterase and the two recombinant esterases were purified. Identification of the physical and biochemical properties of the CBS and PUR esterases revealed that they have the same polypeptide from one gene.

Biodegradation of dibenzothiophene and 4,6-dimethyldibenzothiophene by Sphingomonas paucimobilis strain TZS-7.

Strain TZS-7, tentatively identified as Sphingomonas paucimobilis, was isolated from crude oil for its ability to degrade dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-dmDBT). This strain did not utilize DBT or 4,6-dmDBT as the sole source of sulfur. However, the degradative activity was induced by various aromatic compounds, including DBT, fluorene, anthracene, naphthalene and toluene.

Growth and hydrocarbon production of microalga Botryococcus braunii in bubble column photobioreactors.

Microalga Botryococcus braunii, which produces high levels of liquid hydrocarbons called botryococcenes, was cultivated in bubble column photobioreactors. Algal cells, adapted to low irradiance (3 klx) in the preculture, showed lower biomass and hydrocarbons productivity in the photobioreactor illuminated at high irradiance (10 klx) due to the effects of photoinhibition. The degree of photoinhibition was reduced by partial shading, the lighted volume ratio being varied from 25 to 100%.

Development of an apparatus for monitoring protoplast isolation from plant tissues based on both dielectric and optical methods.

In order to develop a method allowing objective determination of the optimal conditions for the isolation of protoplasts, the process of protoplast isolation from plant tissues was quantitatively evaluated. First, a specialized spectrophotometer cuvette (working volume = 2.0 ml) was designed for the continuous monitoring of protoplast isolation from plant tissues based on the optical method.

Methyl alpha-D-mannopyranoside-responsive release of microencapsulated glucoamylase.

Microcapsules are made of porous membranes through which enzymes or proteins can readily permeate. Glucoamylase was encapsulated into microcapsules in the presence of concanavalin A. Microencapsulated glucoamylase was released from the microcapsules into the bulk phase in the presence of methyl alpha-D-mannopyranoside, while it was not released in the absence of methyl alpha-D-mannopyranoside.

Decolorization of molasses wastewater by Bacillus sp. under thermophilic and anaerobic conditions.

Various microorganisms were screened for their ability to decolorize molasses wastewater under thermophilic and anaerobic conditions. Strain MD-32, which was newly isolated from a soil sample, was selected as the best strain. From taxonomical studies, the strain was concluded to belong to the genus Bacillus, most closely resembling B.

Polyelectrolyte gel transitions: experimental aspects of charge inhomogeneity in the swelling and segmental attractions in the shrinking.

This paper aims to provide a systematic discussion based on our experimental results both previously published and unpublished, to promote better understanding of volume-phase transitions in polyelectrolyte gels. Special attention was paid to the distribution of network charges as well as to the attractive interaction among polymer segments. From looking at how these effects appear in the swelling curves, an exploration of the nature of polyelectrolyte gel transitions was attempted.

Noninvasive visualization of molecular events in the mammalian zygote.

Following fertilization, a number of molecular events are triggered in the mammalian zygote. As biochemical studies using mammalian gametes and zygotes have inherent difficulties, the molecular nature of these processes is currently unclear. We have developed a method to visualize these events.

Formation of intra- and interparticle polyelectrolyte complexes between cationic nanogel and strong polyanion.

Polyelectrolyte complex formation of a strong polyanion, potassium poly(vinyl alcohol) sulfate (KPVS), with positively charged nanogels was studied at 25 degrees C in aqueous solutions with different KCl concentrations (C(s)) as a function of the polyion-nanogel mixing ratio based on moles of anions versus cations. Used as the gel sample was a polyampholytic nanogel consisting of lightly cross-linked terpolymer chains of N-isopropylacrylamide, acrylic acid, and 1-vinylimidazole; thus, the complexation was performed at pH 3 at which the imidazole groups are fully protonated to generate positive charges. Turbidimetric titration was employed to vary the mixing ratio.

Swelling-shrinking behavior of a polyampholyte gel composed of positively charged networks with immobilized polyanions.

Polyampholyte gels were prepared by free radical polymerization of aqueous monomer solutions with the following composition: 69% N-isopropylacrylamide (thermosensitive neutral monomer), 1% N,N'-methylenebisacrylamide (cross-linker), 15% 1-vinylimidazole (cationic monomer), and either 15% acrylic acid (AAc, anionic monomer) or poly(acrylic acid) (PAAc, polyanion). We thus obtained two sorts of polyampholyte gels; that is, G1 with immobilized PAAc and G2 with randomly copolymerized AAc. The equilibrium swelling ratio (Qe) was studied as a function of the pH, NaCl concentration, and temperature.

Stopped-flow spectrophotometric and resonance Raman analyses of aldoxime dehydratase involved in carbon-nitrogen triple bond synthesis.

On stopped-flow analysis of aliphatic aldoxime dehydratase (OxdA), a novel hemoprotein, a spectrum derived from a reaction intermediate was detected on mixing ferrous OxdA with butyraldoxime; it gradually changed into that of ferrous OxdA with an isosbestic point at 421 nm. The spectral change on the addition of butyraldoxime to the ferrous H320A mutant showed the formation of a substrate-coordinated mutant, the absorption spectrum of which closely resembled that of the above intermediate. These observations and the resonance Raman investigation revealed that the substrate actually binds to the heme in OxdA, forming a hexa-coordinate low-spin heme.

High-level expression of a novel amine-synthesizing enzyme, N-substituted formamide deformylase, in Streptomyces with a strong protein expression system.

N-substituted formamide deformylase (NfdA) from Arthrobacter pascens F164 is a novel deformylase involved in the metabolism of isonitriles. The enzyme catalyzes the deformylation of an N-substituted formamide, which is produced from the corresponding isonitrile, to yield the corresponding amine and formate. The nfdA gene from A.

Light/dark cyclic movement of algal culture (Synechocystis aquatilis) in outdoor inclined tubular photobioreactor equipped with static mixers for efficient production of biomass.

Synechocystis aquatilis SI-2 was grown outdoors in a 12.5 cm diam. tubular photobioreactor equipped with static mixers.

Differential roles of renin and angiotensinogen in the feto-maternal interface in the development of complications of pregnancy.

We previously identified a transgenic mouse model that developed pregnancy-associated hypertension (PAH) and intrauterine growth restriction (IUGR) by mating females expressing human angiotensinogen (hANG) with males expressing human renin (hRN). These phenotypic defects were not observed in the opposite type of mating combination, despite the feto-placental overexpression of hRN and hANG detected in both types of crossbreeding. Detailed analysis of transgene localization in the labyrinth and its permeability to the maternal circulation revealed that hRN produced in trophoblast giant cells was secreted into the maternal circulation, whereas hANG, produced in chorionic trophoblasts and trophoblastic epithelium, was undetectable in the maternal plasma, probably due to their distinct spatial and temporal expression in labyrinth.

Nitrile pathway involving acyl-CoA synthetase: overall metabolic gene organization and purification and characterization of the enzyme.

Two open reading frames (nhpS and acsA) were identified immediately downstream of the previously described Pseudomonas chlororaphis B23 nitrile hydratase (NHase) gene cluster (encoding aldoxime dehydratase, amidase, the two NHase subunits, and an uncharacterized protein). The amino acid sequence deduced from acsA shows similarity to that of acyl-CoA synthetase (AcsA). The acsA gene product expressed in Escherichia coli showed acyl-CoA synthetase activity toward butyric acid and CoA as substrates, with butyryl-CoA being synthesized.

Hyper-inducible expression system for streptomycetes.

Streptomycetes produce useful enzymes and a wide variety of secondary metabolites with potent biological activities (e.g., antibiotics, immunosuppressors, pesticides, etc.

Identification of crucial histidines involved in carbon-nitrogen triple bond synthesis by aldoxime dehydratase.

Aldoxime dehydratase (OxdA), which is a novel heme protein, catalyzes the dehydration of an aldoxime to a nitrile even in the presence of water in the reaction mixture. The combination of site-directed mutagenesis of OxdA (mutation of all conserved histidines in the aldoxime dehydratase superfamily), estimation of the heme contents and specific activities of the mutants, and CD and resonance Raman spectroscopic analyses led to the identification of the proximal and distal histidines in this unique enzyme. The heme contents and CD spectra in the far-UV region of all mutants except for the H299A one were almost identical to those of the wild-type OxdA, whereas the H299A mutant lost the ability of binding heme, demonstrating that His(299) is the proximal histidine.

Characterization of BHC80 in BRAF-HDAC complex, involved in neuron-specific gene repression.

BRAF-HDAC complex (BHC) has been shown to contain six components, including BHC80, and to mediate REST-dependent transcriptional repression of neuron-specific genes in non-neuronal cells. In this study, we have examined the functional role(s) of BHC80 in mouse tissues and human cultured cells. Two isoforms of mouse BHC80 were predominantly present in the central nervous system and spermatogenic cells.