For the intracytoplasmic sperm injection (ICSI) procedure in pigs, an electrical pulse (EP) has been used as an effective method for oocyte stimulation, but unlike sperm, EP is unable to induce Ca oscillations. In this study, we investigated the effects of generating artificial Ca oscillations with phospholipase Cζ (PLCζ) mRNA, a candidate sperm factor, on fertilization, embryonic development, and gene expression after ICSI. Firstly, the concentration of PLCζ mRNA of a fixed volume (1.
View Article and Find Full Text PDFRandom and rational mutagenesis of an α-amino acid ester acyl transferase from Sphingobacterium siyangensis AJ2458 (SAET) was conducted to examine the production of aspartame, an α-l-aspartyl-l-phenylalanine methyl ester. We previously reported aspartame production via combination of enzymatic and chemical methods. However, the productivity of the aspartame intermediate by SAET was approximately one-fifth that of l-alanyl-l-glutamine (Ala-Gln), whose production method has already been established.
View Article and Find Full Text PDFIn pigs, the efficiency of embryo production after intracytoplasmic sperm injection (ICSI) is still low because of frequent failure of normal fertilization, which involves formation of two polar bodies and two pronuclei. To clarify the reasons for this, we hypothesized that ICSI does not properly trigger sperm-induced fertilization events, especially intracellular Ca signaling, also known as Ca oscillation. We also suspected that the use of in vitro-matured oocytes might negatively affect fertilization events and embryonic development of sperm-injected oocytes.
View Article and Find Full Text PDFIn pigs, the damaged sperm membrane leads to leakage of phospholipase C-ζ (PLCζ), which has been identified as a sperm factor, and a reduction of oocyte-activating ability. In this study, we investigated whether sperm selected by Percoll gradient centrifugation (Percoll) have sufficient PLCζ, and whether the efficiency of fertilization and blastocyst formation after intracytoplasmic sperm injection (ICSI) using Percoll-selected sperm can be improved. Percoll-selected sperm (Percoll group) or sperm without Percoll selection (Control group) were used.
View Article and Find Full Text PDFBiosci Biotechnol Biochem
September 2016
For the production of enantiopure β-amino acids, enantioselective resolution of N-acyl β-amino acids using acylases, especially those recognizing N-acetyl-β-amino acids, is one of the most attractive methods. Burkholderia sp. AJ110349 had been reported to exhibit either (R)- or (S)-enantiomer selective N-acetyl-β-Phe amidohydrolyzing activity, and in this study, both (R)- and (S)-enantioselective N-acetyl-β-Phe acylases were purified to be electrophoretically pure and determined the sequences, respectively.
View Article and Find Full Text PDFIt has been reported that colon cancer patients with KRAS and BRAF mutations that lie downstream of epidermal growth factor receptor (EGFR) acquire resistance against therapy with anti‑EGFR antibodies, cetuximab and panitumumab. On the other hand, some reports say KRAS codon 13 mutation (p.G13D) has lower resistance against anti-EGFR antibodies, thus there is a substantial need for detection of specific KRAS mutations.
View Article and Find Full Text PDFGM3 synthase (ST3GAL5) is the first biosynthetic enzyme of a- and b-series gangliosides. Patients with GM3 synthase deficiency suffer severe neurological disability and deafness. Eight children (ages 4.
View Article and Find Full Text PDFGenetic testing prior to treatment, pharmacogenetic analysis, is key to realizing personalized medicine which is a topic that has attracted much attention recently. Through the optimization of therapy selection and dosage, a reduction in side effects is expected. Genetic testing has been conducted as a type of pharmacogenetic analysis in recent years, but it faces challenges in terms of cost effectiveness and its complicated procedures.
View Article and Find Full Text PDFThe aim of the present study was to examine the feasibility of fluorescent in situ hybridization (FISH) for detecting a chromosome 1-specific sequence as a means of assessing the ploidy of porcine parthenotes. In vitro-matured oocytes with the first polar body (PB) were electrically activated; some were treated with cytochalasin B to prevent second PB extrusion (1PB embryos), and the others extruded the second PB (2PB embryos). At the 2-cell stage, one and two FISH signals were detected in each nucleus of 2PB and 1PB embryos, respectively.
View Article and Find Full Text PDFEndo-alpha-N-acetylgalactosaminidase catalyzes the release of Galbeta1-3GalNAc from the core 1-type O-glycan (Galbeta1-3GalNAcalpha1-Ser/Thr) of mucin glycoproteins and synthetic p-nitrophenyl (pNP) alpha-linked substrates. Here, we report the enzymatic syntheses of core 1 disaccharide-containing glycopeptides using the transglycosylation activity of endo-alpha-N-acetylgalactosaminidase (EngBF) from Bifidobacterium longum. The enzyme directly transferred Galbeta1-3GalNAc to serine or threonine residues of bioactive peptides such as PAMP-12, bradykinin, peptide-T and MUC1a when Galbeta1-3GalNAcalpha1-pNP was used as a donor substrate.
View Article and Find Full Text PDFThe ganglioside GM3 synthase (SAT-I), encoded by a single-copy gene, is a primary glycosyltransferase for the synthesis of complex gangliosides. In SAT-I null mice, hearing ability, assessed by brainstem auditory-evoked potentials (BAEP), was impaired at the onset of hearing and had been completely lost by 17 days after birth (P17), showing a deformity in hair cells in the organ of Corti. By 2 months of age, the organ of Corti had selectively and completely disappeared without effect on balance or motor function or in the histology of vestibule.
View Article and Find Full Text PDFActa Crystallogr Sect F Struct Biol Cryst Commun
December 2008
The integral membrane protein Mhp1 from Microbacterium liquefaciens transports hydantoins and belongs to the nucleobase:cation symporter 1 family. Mhp1 was successfully purified and crystallized. Initial crystals were obtained using the hanging-drop vapour-diffusion method but diffracted poorly.
View Article and Find Full Text PDFThe nucleobase-cation-symport-1 (NCS1) transporters are essential components of salvage pathways for nucleobases and related metabolites. Here, we report the 2.85-angstrom resolution structure of the NCS1 benzyl-hydantoin transporter, Mhp1, from Microbacterium liquefaciens.
View Article and Find Full Text PDFThe amelogenin (AMEL) gene exists on both sex chromosomes of various mammalian species and the length and sequence of the noncoding regions differ between the two chromosome-specific alleles. Because both forms can be amplified using a single primer set, the use of AMEL in polymerase chain reaction (PCR)-based methods has facilitated sex identification in various mammalian species, including cattle, sheep and humans. In this study, we designed PCR primers to yield different-sized products from the AMEL genes on the X (AMELX) and Y (AMELY) chromosomes of pigs.
View Article and Find Full Text PDFThe gene hyuP from Microbacterium liquefaciens AJ 3912 with an added His6 tag was cloned into the expression plasmid pTTQ18 in an Escherichia coli host strain. The transformed E. coli showed transport of radioisotope-labeled 5-substituted hydantoins with apparent K(m) values in the micromolar range.
View Article and Find Full Text PDFThe possibility of using aged porcine oocytes treated with caffeine, which inhibits the decrease in M-phase promoting factor activity, for pig cloning was evaluated. Cumulus-oocyte complexes (COCs) were cultured initially for 36 h and subsequently with or without 5 mM caffeine for 24 h (in total for 60 h: 60CA+ or 60CA- group, respectively). As a control group, COCs were cultured for 48 h without caffeine (48CA-).
View Article and Find Full Text PDFA DNA fragment from Microbacterium liquefaciens AJ 3912, containing the genes responsible for the conversion of 5-substituted-hydantoins to alpha-amino acids, was cloned in Escherichia coli and sequenced. Seven open reading frames (hyuP, hyuA, hyuH, hyuC, ORF1, ORF2, and ORF3) were identified on the 7.5 kb fragment.
View Article and Find Full Text PDFBiosci Biotechnol Biochem
March 2005
A hydantoin racemase that catalyzed the racemization of 5-benzyl-hydantoin was detected in a cell-free extract of Microbacterium liquefaciens AJ 3912, a bacterial strain known to produce L-amino acids from their corresponding DL-5-substituted-hydantoins. This hydantoin racemase was purified 658-fold to electrophoretic homogeneity by serial chromatography. The N-terminal amino acid sequence of the enzyme showed homology with known hydantoin racemases from other microorganisms.
View Article and Find Full Text PDFTwo genes, gusB and gusC, from a natural fecal isolate of Escherichia coli are shown to encode proteins responsible for transport of beta-glucuronides with synthetic [(14)C]phenyl-1-thio-beta-d-glucuronide as the substrate. These genes are located in the gus operon downstream of the gusA gene on the E. coli genome, and their expression is induced by a variety of beta-d-glucuronides.
View Article and Find Full Text PDFPuromycin N-acetyl transferase gene (pac), of which the gene product catalyzes antibiotic puromycin (an effective inhibitor of protein synthesis), has been widely used as a dominant selection marker in embryonic stem (ES) cell-mediated transgenesis. The present study is the first to report on the usefulness of puromycin for production of enhanced green fluorescent protein (EGFP) transgenic piglets after somatic cell cloning and embryo transfer. Somatic cells isolated from porcine fetuses at 73 days of gestation were immediately electroporated with a transgene (pCAG-EGFPac) carrying both EGFP cDNA and pac.
View Article and Find Full Text PDFXylitol production from D-arabitol by the membrane and soluble fractions of Gluconobacter oxydans was investigated. Two proteins in the soluble fraction were found to have the ability to increase xylitol production. Both of these xylitol-increasing factors were purified, and on the basis of their NH(2)-terminal amino acid sequences the genes encoding both of the factors were cloned.
View Article and Find Full Text PDFA general strategy for the amplified expression in Escherichia coli of membrane transport and receptor proteins from other bacteria is described. As an illustration we report the cloning of the putative alpha-ketoglutarate membrane transport gene from the genome of Helicobacter pylori, overexpression of the protein tagged with RGS(His)6 at the C-terminus, and its purification in mg quantities. The retention of structural and functional integrity was verified by circular dichroism spectroscopy and reconstitution of transport activity.
View Article and Find Full Text PDFBiosci Biotechnol Biochem
September 2003
A potent producer of D-arabitol was isolated by screening of natural sources and identified as Metschnikowia reukaufii AJ14787. Resting cells of this strain can efficiently produce D-arabitol from D-glucose with a weight yield of more than 60%, and can also produce D-arabitol from several other types of sugars such as polyols, ketoses, and aldoses. To improve productivity, various culture conditions such as temperature and the concentrations of D-glucose and nitrogen sources were examined.
View Article and Find Full Text PDFXylitol dehydrogenase (XDH) was purified from the cytoplasmic fraction of Gluconobacter oxydans ATCC 621. The purified enzyme reduced D-xylulose to xylitol in the presence of NADH with an optimum pH of around 5.0.
View Article and Find Full Text PDFBiosci Biotechnol Biochem
December 2002
Microorganisms capable of producing xylitol from D-arabitol were screened for. Of the 420 strains tested, three bacteria, belonging to the genera Acetobacter and Gluconobacter, produced xylitol from D-arabitol when intact cells were used as the enzyme source. Among them, Gluconobacter oxydans ATCC 621 produced 29.
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