Mass spectral measurements by electrospray ionization mass spectrometry (ESI-MS) detected the ions of β-cyclodextrin (βCD) or branched βCDs (glucosyl-, galactosyl-, mannosyl- and maltosyl-βCD)–prostaglandins (PGs: PGA2, PGD2, PGE1, PGE2, PGF2α and PGJ2) complexes, i.e., βCD–PG complexes, with a host:guest ratio of 1:1 in the negative ion mode. This is the first study to report the ions of branched βCD–PG complexes using ESI-MS. The inclusion complexes were determined by a flow injection analysis using acetonitrile/water. We could confirm by this method the presence of a βCD–PGE2 complex with a host:guest ratio of 1:1 in a solution-dissolved pharmaceutical formulation consisting of βCD–PGE2 (ProstarmonTM E tablet).
In our studies on the development of new promoters for the root formation of tree cuttings, 4-trifluoromethylindole-3-acetic acid (4-CF3-IAA), a new fluorinated auxin, was synthesized via 4-trifluoromethylindole and 4-trifluoromethylindole-3-acetonitrile by using 2-methyl-3-nitrobenzotrifluoride as the starting material. As a control compound for comparing biological activities, 4-methylindole-3-acetic acid (4-CH3-IAA) was also synthesized by using 2,3-dimethylnitrobenzene as the starting material. The biological activities of these compounds were compared by three bioassays with those of indole-3-acetic acid and 4-chloroindole-3-acetic acid (4-Cl-IAA), which, like 4-CF3-IAA and 4-CH3-IAA, has a substituent at the 4-position of the indole nucleus. 4-CF3-IAA showed strong root formation-promoting activity with black gram cuttings which was 1.5 times higher than that of 4-(3-indole)butyric acid at 1×10−4 M. 4-CH3-IAA, however, only weakly promoted root formation in spite of its strong inhibition of hypocotyl growth in Chinese cabbage and promotion of hypocotyl swelling and lateral root formation in black gram. On the other hand, 4-CF3-IAA demonstrated weaker activities than 4-CH3-IAA and 4-Cl-IAA in these two bioassays.
D-Trigalacturonic acid methylglycoside (3) was synthesized to evaluate the previously synthesized sulfur analogue 1 by comparison. The NOE experiments revealed that both 3 and 1 took on a similar conformation around their glycosyl linkage.
Two new cyclohexene compounds related to theobroxide (3) were isolated from the mycelia of Lasiodiplodia theobromae OCS71. The structures of these compounds were determined to be (4S,5S)-4,5-dihydroxy-2-methyl-cyclohex-2-enone (1) and (3aS,4R,5S,7aR)-4,5-dihydroxy-7-methyl-3a,4,5,7a-tetrahydrobenzo[1,3]dioxol-2-one (2) by means of spectroscopic analyses and chemical correlation to 3. Compound 2 was shown to take up the carbonate ion to form a carbonic acid ester non-enzymatically. The compounds also showed potato micro-tuber-inducing activities at a concentration of 10−3 M, using a culture of single-node segments of potato stems in vitro.
Regioselectivity of Larock indole synthesis, a palladium-catalyzed heteroannulation between o-iodoaniline and internal acetylene, was estimated using acetylenes substituted with ester and/or Boc-protected amine at the homopropargylic position and with perbenzyl- and unprotected glucose. Low to moderate regioselectivities were observed in all the cases, indicating these functional groups do not exert good directing effects, in the Larock indole synthesis.
Brassinolide (BL), a plant 7-oxalactone-type steroid hormone, is one of the active brassinosteroids (BRs) that regulates plant growth and development. BL is biosynthesized from castasterone by the cytochrome P450 monooxygenase, CYP85A2. We showed that a Pichia pastoris transformant that synchronously expresses Arabidopsis P450 reductase gene ATR1 and P450 gene CYP85A2 converts teasterone and typhasterol to 7-oxateasterone and 7-oxatyphasterol, respectively. Thus, CYP85A2 catalyzes the lactonization reactions of not only castasterone but also teasterone and typhasterol. The two 2-deoxy-7-oxalactone-type BRs were identified in Arabidopsis plants. Although the reversible conversion between 7-oxateasterone and 7-oxatyphasterol was observed in vivo, no conversion of 7-oxatyphasterol to BL was observed. The biological activity of 7-oxatyphasterol toward Arabidopsis hypocotyl elongation was nearly the same as that of castasterone. These results suggest that a new BR biosynthetic pathway, a BR lactonization pathway, functions in Arabidopsis and plays an important role in regulating the concentration of active BRs, even though the metabolism of 7-oxatyphasterol to BL is still unknown.
Two phenolics, 1,2,6-trigalloylglucose (1) and 1,2,3,6-tetragalloylglucose (2), isolated from the stem-bark of Juglans mandshurica were evaluated for their antioxidative activities. The results showed that compounds 1 and 2 exhibited strong scavenging activities against 1,1′-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis-(3-ethylbenzenthiazoline-6-sulphonic) acid (ABTS•+), and superoxide radicals (O2•−), and also had a significant inhibitory effect on lipid peroxidation and low-density lipoprotein (LDL) oxidation. The strong superoxide radical scavenging of 1 and 2 resulted from the potential competitive inhibition with xanthine at the active site of xanthine oxidase (OX). In addition, compounds 1 and 2 displayed significant lipoxygenase inhibitory activity, the mode of inhibition also being identified as competitive. In comparison, the antioxidative activities of compounds 1 and 2, together with gallic acid, indicated that the number of galloyl moieties could play an important role in the antioxidative activity.
Formation of the intermolecular β-sheet is a key event in the aggregation of 42-residue amyloid-β (Aβ42). We have recently identified a physiological and toxic conformer, the turn positions of which are slightly different from each other, in the aggregates of E22K-Aβ42 (one of the mutants related to cerebral amyloid angiopathy). However, it remains unclear whether the intermolecular β-sheet in the E22K-Aβ42 aggregates is parallel or antiparallel. We prepared an equal mixture of E22K-Aβ42 aggregates labeled at Cα and those labeled at C=O with 13C, whose intermolecular 13C–13C distance was estimated by solid-state NMR using rotational resonance (R2). The intermolecular proximity of β-strands at positions 21 and 30 was less than 6 Å, supporting the existence of the intermolecular parallel β-sheet in the E22K-Aβ42 aggregates as well as in wild-type Aβ42 aggregates. The results also suggest that each conformer would not accumulate alternately, but form a relatively large assembly.
Two flavan-3-ol glycosides together with seven flavan-3-ols were isolated from stems of the mangrove plant, Rhizophora stylosa. Their structures were established as glabraoside A (7) and glabraoside B (8) by spectroscopic and chemical methods. The antioxidative activity of these isolated compounds evaluated by the diphenylpicrylhydrazyl (DPPH) radical scavenging reaction was higher than that of L-ascorbic acid.
Cecropins belong to the antibacterial peptides family and are induced after injection of bacteria or their cell-wall components. By silkworm cDNA microarray analysis, a novel type of Cecropin family gene was identified as a cDNA up-regulated in early embryo, 1 day after oviposition. The cDNA isolated was 394 bp with 198 ORF translating 65 amino acids, encoding BmCecropin-E (BmCec-E). Using Southern hybridization and genome search analysis, the number of BmCec-E gene was estimated to be at least two per haploid, which consisted of two exons, as in other Cecropin family members. BmCec-E mRNA was expressed transiently 1 day after egg-laying (AEL, germ-band formation stage), and was specifically expressed in the degenerating intestine during the pre-pupal and pupal stages, unlike other Cecropin family genes. Immune challenge analysis showed that BmCec-E gene expression was more strongly induced by Escherichia coli (gram-negative) than by Micrococus luteus (gram-positive), and not by virus injection. By bacterial challenge, expression of BmCec-E mRNA was induced 12 h after injection, and was maintained for 24 h. Expression of BmCec-E after immune challenge was observed strongly in excretory organs, such as hindgut and malphigian, slightly in fat body, skin, and midgut.
An expression system for aqualysin I from Thermus aquaticus YT-1, a thermophilic serine protease belonging to the proteinase K family, in Escherichia coli is available, but the efficiency of production has been rather low for detailed analysis of the product. We developed a maltose biding protein (MBP)-fused proaqualysin I expression plasmid (pMAQ-c2Δ) in which MBP is attached to the N-terminus of proaqualysin I. MBP appeared effectively to suppress the folding-promoting activity of the N-terminal propeptide when the bacteria were grown at 30 °C, leading to a massive accumulation of fusion aqualysin I precursor. The precursor was converted efficiently to mature aqualysin I by heat treatment at 70 °C, enabling us to obtain 40 times more aqualysin I than is available using expression systems such as pAQNΔC105. By analyzing the product of the pMAQ-c2Δ-derived inactive mutant expression vector, pMAQ-S222A, it was confirmed that aqualysin I was initially expressed as a whole fusion protein and then processed autocatalytically.
Pseudomonas putidabenF, benK, benE1, and benE2 genes encode proteins belonging to benzoate transporter super family, but those functions have not yet been elucidated. In this study we analyzed the functions of these gene products using the yeast Saccharomyces cerevisiae. P. putida gene products expressed in yeast cells were localized to the yeast plasma membrane and were involved in taking up benzoate into the cells. According to the sensitivity of yeast cell-growth to benzoate, it is proposed that benK, benE1, and benE2 gene products function as transporters, that take up benzoate into the cells, whereas the benF gene product functions as an efflux pump of benzoate.
Hevea brasiliensis Müll. Arg. is a tree that produces natural rubber, an industrially vital isoprenoid polymer. Biosynthesis of natural rubber is known to take place biochemically by a mevalonate (MVA) pathway, but molecular biological characterization of related genes has been insufficient. From H. brasiliensis, we obtained full-length cDNA of genes encoding all of the enzymes that catalyze the six steps of the MVA pathway. Alignment analysis and phylogenetic analysis revealed that in H. brasiliensis there are three acetyl-CoA acetyltransferase genes, two HMG-CoA synthase (HMGS) genes, and four HMG-CoA reductase (HMGR) genes. Gene expression analysis by type of tissue indicated that MVA pathway genes were highly expressed in latex, as compared to other types of tissue and that HMGS and HMGR, which exist in multiple copies, have different expression patterns. Moreover, these MVA pathway genes in H. brasiliensis were found to complement MVA pathway deletion mutations in yeast.
Pseudomonas sp. A-01, isolated as a strain with chitosan-degrading activity, produced a 28 kDa chitosanase. Following purification of the chitosanase (Cto1) and determination of its N-terminal amino acid sequence, the corresponding gene (cto1) was cloned by a reverse-genetic technique. The gene encoded a protein, composed of 266 amino acids, including a putative signal sequence (1-28), that showed an amino acid sequence similar to known family-46 chitosanases. Cto1 was successfully overproduced and was secreted by a Brevibacillus choshinensis transformant carrying the cto1 gene on expression plasmid vector pNCMO2. The purified recombinant Cto1 protein was stable at pH 5–8 and showed the best chitosan-hydrolyzing activity at pH 5. Replacement of two acidic amino acid residues, Glu23 and Asp41, which correspond to previously identified active centers in Streptomyces sp. N174 chitosanase, with Gln and Asn respectively caused a defect in the hydrolyzing activity of the enzyme.
Novel basic proteins, duck basic protein small 1 (dBPS1) and 2 (dBPS2), were isolated from duck egg white by cation-exchange and gel filtration chromatography. Protein sequence analyses indicated that they possessed 39 amino acid residues with three disulfide bonds. The amino acid sequence of dBPS1 showed 45% identity with dBPS2. The amino acid sequence of dBPS2 was the same as cygnin, a small protein from black swan, and strongly homologous with meleagrin from turkey and chicken. Phylogenic relationships implied that dBPS1 and dBPS2 share a common ancestry with cygnin and meleagrin. Based on MALDI-TOF mass spectra, the molecular masses of dBPS1 and dBPS2 were 4,373, and the 4,486 Da. pI of dBPS1 and dBPS2 elucidated by isoelectric focusing were 9.35 and 9.44. FT-IR spectra classified these proteins as (β) proteins. Both dBPS1 and dBPS2, possessed high heat stability, Td 101.2 and 98.3 °C. Indirect ELISA results showed that the dBPS1/dBPS2-related proteins were distributed in the oviduct and gallbladder.
Cytochrome c552 (PH c552) from moderately thermophilic Hydrogenophilus thermoluteolus exhibits stability intermediate between those of cytochrome c552 (HT c552) from thermophilic Hydrogenobacter thermophilus and cytochrome c551 (PA c551) from mesophilic Pseudomonas aeruginosa. To understand the mechanism of stabilization of PH c552, we introduced mutations into PH c552 at five sites, which, in HT c552, are occupied by the amino acids responsible for stability higher than the less stable PA c551. When PH c552 Val-78 was mutated to Ile, as found in HT c552, the resulting variant showed increased stability. Mutation of Ala-7, Met-13, and Tyr-34 to the corresponding residues in PA c551 (Phe, Val, and Phe, respectively) resulted in destabilization. We also found that PH c552 Lys-43 contributed to stability through the formation of an attractive electrostatic interaction with Asp-39. These results suggest that the intermediate stability of PH c552 is due to the amino acids at these five sites.
3,3′-Dinitrobisphenol A (dinitro-BPA) is formed in a mixture of bisphenol A (BPA) and nitrite under acidic conditions. It shows genotoxicity in male ICR mice on a micronucleus test, but its estrogenic activity has not been examined in vivo. We examined its estrogenic activity using goldfish (Carassius auratus) by measuring plasma levels of vitellogenin (VTG) by the ELISA method. Expression of VTG didn’t increase in the plasma of goldfish intraperitoneal injected with dinitro-BPA at a dose of 10 mg/kg of body weight. We also examined the genotoxicity of dinitro-BPA by single-cell gel electrophoresis (comet assay) and a micronucleus test using goldfish. The DNA tail moment of blood cells increased after intraperitoneal injection of dinitro-BPA. Dinitro-BPA at the same dose significantly increased micronucleus frequency in gills of goldfish. On the other hand, BPA did not significantly increase the frequency of micronucleated cells. In conclusion, we found that dinitro-BPA did not show estrogenic activity, but had genotoxic potency stronger than that of BPA.
Several ω-laurolactam degrading microorganisms were isolated from soil samples. These strains were capable of growing in a medium containing ω-laurolactam as sole source of carbon and nitrogen. Among them, five strains (T7, T31, U124, U224, and U238) were identified as Cupriavidus sp. T7, Acidovorax sp. T31, Cupriavidus sp. U124, Rhodococcus sp. U224, and Sphingomonas sp. U238, respectively. The ω-laurolactam hydrolyzing enzyme from Rhodococcus sp. U224 was purified to homogeneity, and its enzymatic properties were characterized. The enzyme acts on ω-octalactam and ω-laurolactam, but other lactam compounds, amides and amino acid amides, cannot be substrates. The enzyme gene was cloned, and the deduced amino acid sequence showed high homology with 6-aminohexanoate-cyclic-dimer hydrolase (EC 22.214.171.124) from Arthrobacter sp. KI72 and Pseudomonas sp. NK87. Enzymatic synthesis of 12-aminolauric acid was performed using partially purified ω-laurolactam hydrolase from Rhodococcus sp. U224.
A sensitive and simple liquid chromatography/tandem mass spectrometry (LC-MS/MS) method was developed for the detection of alginate oligosaccharides (AOs) in mouse plasma and urine after oral administration. In an AO mixture, dimer, trimer, and tetramer were detected by LC-MS/MS equipped with an anion-exchange column with extremely high sensitivity. By this method, we detected certain levels of AOs in samples prepared from mouse plasma and urine after a single oral administration of the AO mixture. Based on a calibration curve made with an AO trimer peak area as a standard, the maximum plasma and urine concentrations of AOs were estimated to be 24.5 μg/ml at 5 min and 425.5 μg/ml at 30 min, respectively. These results suggest that the LC-MS/MS method is well suited to pharmacokinetic analysis of AOs in an in vivo system, and that some of orally administered AOs, at least from dimer to tetramer, are absorbed by digestive organs promptly, and that unaltered, these oligomers were excreted into an urine after a single oral administration to a mouse.
A gene encoding a glycoside hydrolase (GH) family 36 α-galactosidase was cloned from Yersinia pestis biovar Microtus str. 91001 and expressed in Escherichia coli. The purified recombinant α-galactosidase (Aga-Y) was optimally active at 37 °C and pH 6.8. The features of temperature profile, thermoliability, kinetics, and amino acid composition indicated that Aga-Y had properties of a cold-adapted enzyme.
Curcumin analogs were first investigated for their inhibitory effects on thioredoxin reductase (TrxR). Most of them were more potent TrxR inhibitors than natural curcumin. The structure-activity relationship was summarized, and the curcumin analog was found to inhibit TrxR irreversibly in a time-dependent manner. The action was caused by covalent modification of the redox-active residues Cys497 and Sec498 in TrxR.
Disruption of an SCS2 ortholog impaired the growth of the alkane-assimilating yeast Yarrowia lipolytica on n-alkanes, particularly on n-decane, although the mRNA level of the ALK1 gene encoding a highly inducible cytochrome P450ALK was not much affected. The same disruption did not cause inositol auxotrophy, implying that Y. lipolyticaSCS2 has a different function from its Saccharomyces cerevisiae counterpart.
We isolated a cDNA clone with homology to known desaturase genes from Oblongichytrium sp., recently classified as a new genus of thraustochytrids (Labyrinthulomycetes), and found that it encoded Δ5-desaturase by its heterologous expression in yeast. The enzyme had higher activity toward 20:4n-3 than 20:3n-6, indicating that this Δ5-desaturase can be used in the production of n-3 polyunsaturated fatty acids in transgenic organisms.
Scytalidopepsin A, a pepstatin-insensitive acid endopeptidase from the fungus Scytalidium lignicolum was found to be a member of the sedolisin family of serine-carboxyl peptidases through analyses of the amino acid sequences of peptides derived from the reduced, pyridylethylated enzyme by enzymatic digestion. Hence it should be renamed scytalidolisin (or Scytalidium sedolisin).
Arabidopsis E3 ligase salt- and drought-induced RING-finger 1 (SDIR1) has been found to be involved in abscisic acid (ABA)-related stress signaling. SDIR1-overexpressing Arabidopsis plants exhibit improved tolerance to drought. Tobacco (Nicotiana tabacum) and rice (Oryza sativa) are two important agronomic crop plants. To determine whether SDIR1 enhances drought resistance in crop plants, SDIR1 transgenic tobacco and rice plants were generated. Ectopic expression of SDIR1 in both plants conferred improved drought tolerance ability. These results suggest that SDIR1 can function as a drought-tolerance gene in both dicotyledons and monocotyledons, and that it can serve as a drought-tolerance engineering candidate gene in crop plants.
We evaluated the effects of a casein hydrolysate (CH) prepared from Aspergillus oryzae protease on rat adjuvant arthritis, a model of human rheumatoid arthritis. CH was administered orally once a day to the animals for 22 d after the adjuvant injection. CH suppressed swelling in the adjuvant-uninjected hind paws, and a higher dose of CH suppressed the increase in arthritic score and swelling of the adjuvant-injected hind paws. A histopathological examination revealed evidence that the higher dose of CH suppressed the articular changes in the rats. In addition, CH suppressed the production of nitric oxide and prostaglandin E2 in the plasma of the rats. These results suggest that CH had a suppressive effect on adjuvant arthritis by inhibiting the acute and chronic inflammatory reactions.
We investigated to determine why heating of squid muscle at 60 °C induced the liberation of actin from myofibrils. When a mixture of a myofibrillar fraction and a low-molecular sarcoplasmic fraction prepared from squid muscle was heated at 60 °C, actin liberation occurred. When a myofibrillar fraction was heated with ATP, AMP, or IMP, actin liberation occurred. Hence, AMP is perhaps one of the factors causing actin liberation in postmortem squid muscle. It was found that AMP and IMP reversibly dissociated actomyosin of chicken, bovine, and porcine skeletal muscles into actin and myosin on incubation at 0 °C at pH 7.2 in 0.2 M
KCl. These results led us to conclude that AMP and IMP were the most responsible factors causing actin liberation from myofibrils in the heated muscle and causing reversible dissociation of actomyosin on storage of skeletal muscle at a low temperature. Hence, AMP and IMP are possible factors causing the resolution of rigor mortis in muscles.
Dioscorea batatas Decne (DBD) is used to heal various disorders of the kidney and lungs as an herbal agent in Korea. The purpose of the present study was to determine whether the DBD glycoprotein regulates the inflammatory reaction stimulated by phorbol-12-myristate 13-acetate plus calcium ionophore A23187 (PMACI) in human mast cells (HMC-1). The results indicate that DBD glycoprotein decreased gene expression of interleukin (IL)-1β and cyclooxygenase (COX)-2 in PMACI-stimulated HMC-1 cells through blocking of phosphorylation of p44/42 mitogen-activated protein kinase (MAPK) and p38 MAPK and DNA binding activities of nuclear factor (NF)-κB and activator protein (AP)-1. The production of intracellular reactive oxygen species (ROS) and nitric oxide (NO) is gradually reduced by concentration-dependent DBD glycoprotein treatment in PMACI-stimulated HMC-1 cells. Hence, we propose the hypothesis that DBD glycoprotein can serve as a potent anti-inflammatory agent in the treatment of inflammatory allergic diseases through inhibition of inflammation-related signal transduction in mast cell activation.
We investigated the effect of dietary phospholipid (PL) concentrate from bovine milk on the epidermis. Thirteen-week-old hairless male and female mice (Hos:HR-1) were separated into two experimental groups, each fed two experimental diets: the control group and the PL group. The mice were given the experimental diets for 6 weeks. Stratum corneum hydration and transepidermal water loss (TEWL) were measured using Corneometer CM825 and Tewameter TM300 (Courage and Khazaka Electronics, Cologne, Germany) at 3 weeks and 6 weeks. After the feeding period, ceramides in stratum corneum were analyzed. We found that stratum corneum hydration and ceramides in the PL group were significantly higher than those in the control group and that TEWL in the PL group tended to decrease. These results indicate that dietary PL concentrate improves epidermal function by increasing the amount of ceramides, resulting in higher hydration.
Carotenoids are used in wide-ranging food applications, but they are susceptible to degradation by many factors including light. We examined the photodegradation of five kinds of carotenoids and three kinds of anthocyanins to clarify which structures of pigments were favorable to accelerated degradation by sulfides under UVA irradiation. Under UVA irradiation, crocetin and crocin were decomposed more rapidly in the presence of dimethyl tetrasulfide than in the absence of the sulfide, but not as rapidly as β-carotene, zeaxanthin and β-cryptoxanthin were. However, cyanidin was decomposed more slowly in the presence of sulfide than in the absence of sulfide. Moreover, the photodegradation of kuromanin and keracyanin was not affected by the addition of a sulfide. We also examined the mechanism for this accelerated degradation. Normal hexane was more favorable to the photodegradation of β-carotene than methanol and ethanol. The accelerated degradation was inhibited by free radical scavengers, but enhanced by the addition of deuterium oxide. These results suggest that conjugated double bonds were favorable to the accelerated photodegradation by sulfide and that this reaction was mediated by free radicals.
It has been reported that the circulating glucose-dependent insulinotropic polypeptide (GIP) levels were reduced by an intake of some foods/drugs capable of delaying carbohydrate digestion/absorption. In this study, we revealed that feeding rats with dietary resistant starch reduced the GIP mRNA levels along the entire length of the jejunoileum in both Wistar and type 2 diabetic GK rats.
Mulberry 1-deoxynojirimycin (DNJ) is a potent α-glucosidase inhibitor. Although it is useful for the treatment of diabetes, the human absorption and metabolism of DNJ have never been characterized. We developed a method using hydrophilic interaction chromatography coupled with ion trap tandem mass spectrometry, and found that orally administered DNJ was absorbed into the blood and then excreted into the urine.
A specific and qualitative detection method for buckwheat in foods using the polymerase chain reaction (PCR) was developed. Trace amounts of buckwheat in commercial food products were qualitatively detected by this method. It should be reliable for detecting buckwheat residues in processed foods and practical for monitoring the labeling system for allergenic food materials.
Trp-P-2(3-amino-1-methyl-5H-pyrido [4,3-b] indole) ingestion for 42 d by C3H/HeJJcl mice caused elevation of serum alanine transaminase (ALT) activity and several signs of liver injury. These alterations were not observed in mice fed the diet supplemented with 10% miso. This suggests a preventive effect of miso as to Trp-P-2 induced liver injury.
Indole-3-carbinol (I3C) has been reported to exert anticancer activity in vivo. However, its anticancer mechanism has not been fully elucidated. In this study, we demonstrate that I3C suppressed tumor-induced angiogenesis and tube formation of endothelial cells. I3C also induced apoptosis in endothelial cells by activating the caspase cascade. We propose that I3C exerts its anticancer effect through the induction of endothelial apoptosis.
Molybdenum (Mo) and chromium (Cr) in 79 Japanese breast milk samples were measured by inductively coupled plasma-mass spectrometry. For Mo, 51 samples (64.6%) showed less than 5 ng/ml and only 12 samples (15.2%) showed more than 10 ng/ml. The range and median were <0.1 to 25.91 and 3.18 ng/ml respectively. For Cr, 38 samples (48.1%) showed less than 1 ng/ml, 20 samples (25.3%) showed 1 to 2 ng/ml, and only six samples (7.6%) showed more than 5 ng/ml. The range and median were <0.1 to 18.67 and 1.00 ng/ml respectively.
Salinivibrio costicola subsp. yaniae is a moderately halophilic bacterium which can grow over a wide range of salinity. In response to external osmotic stress (1–3 M NaCl), S. costicola subsp. yaniae can accumulate ectoine, glycine betaine, and glutamate as compatible solutes. We used suicide plasmids pSUP101 to introduce transposon Tn1732 into S. costicola subsp. yaniae via Escherichia coli SM10 mediated by conjugation. One Tn1732-induced mutant, MU1, which was very sensitive to the external salt concentration, was isolated. Mutant MU1 did not grow above 1.5 M NaCl and did not synthesize ectoine, but accumulated Nγ-acetyldiaminobutyrate, an ectoine precursor, as confirmed by 1H-NMR analysis. From these data, we concluded that ectoine performs a key role in osmotic adaptation towards high salinity environments in strain S. costicola subsp. yaniae.
Debaryomyces vanrijiae MH201 produces formate oxidase (FOD) at estimated pI values by native isoelectric focusing of 5.1, 5.4, and 5.9. We cloned and expressed three formate oxidase cDNAs, FOD1, FOD2, and FDO3, of the yeast using Escherichia coli. The open reading frames of FOD1, FOD2, and FDO3 were 1,731 bp long, and encoded 576-amino acid polypeptides with molecular masses of 64,142, 63,794, and 63,836 Da respectively. Expression of FOD1, FOD2, and FOD3 resulted in the production of three isozymes, with pI values of 5.1, 5.9, and 5.9 respectively. Co-expression of FOD1 and FOD2 and of FOD1 and FOD3 resulted in the production of additional isozymes with pI values, of 5.4. The three amino acid sequences of FOD1, FOD2, and FOD3 contained a consensus motif of a flavin adenine dinucleotide binding site in their N-terminal parts and a glucose-methanol-choline oxidoreductase signature pattern, suggesting that formate oxidase ought to be classified in the glucose-methanol-choline oxidoreductase family.
A slightly thermophilic strain, CBS-01, producing trehalose synthase (TreS), was isolated from geothermal water in this study. According to the phenotypic characteristics and phylogenetic analysis of the 16s rRNA gene sequence, it was identified as Meiothermus ruber. The trehalose synthase gene of Meiothermus ruber CBS-01 was cloned by polymerase chain reaction and sequenced. The TreS gene consisted of 2,895 nucleotides, which specified a 964-amino-acid protein. This novel TreS catalyzed reversible interconversion of maltose and trehalose.
Biosurfactant production by Pichia anomala PY1, a thermotorelant strain isolated from fermented food, was examined as grown in media containing various carbon and nitrogen sources. The optimal conditions for biosurfactant production included 4% soybean oil as carbon source at pH 5.5 at 30 °C for 7 d. Under these conditions, the surface tension of the medium decreased to 28 mN/m with oil displacement measured at 69.43 cm2. Comparative studies of biosurfactant production in media containing glucose or soybean oil were performed. The biosurfactants obtained were isolated and purified by chromatographic methods. The molecular weights of samples were further investigated by mass spectrometry. In medium containing glucose, biosurfactants of molecular weights of 675, 691, and 707 were obtained, while those isolated from medium containing soybean oil were of molecular weights of 658, 675, and 691. These results reveal that sophorolipid compounds containing fatty acids of C20 and C18:1 were produced from both media.
It is well known that in oxidative fermentation microbial growth is improved by the addition of glycerol. In a wild strain, glycerol was converted rapidly to dihydroxyacetone (DHA) quantitatively in the early growth phase by the action of quinoprotein glycerol dehydrogenase (GLDH), and then DHA was incorporated into the cells by the early stationary phase. Two DHA reductases (DHARs), NADH-dependent (NADH-DHAR) (EC 126.96.36.199) and NADPH-dependent (NADPH-DHAR) (EC 188.8.131.52), were detected in the same cytoplasm of Gluconobacter suboxydans IFO 3255. The former appeared to be inducible and labile in nature while the latter was constitutive and stable. The two DHARs were separated each other and were finally purified to crystalline enzymes. This report might be the first one dealing with NADPH-DHAR that has been crystallized. The two DHARs were specific only to DHA reduction to glycerol and thus contributed to cytoplasmic DHA metabolism, resulting in an improved biomass yield with the addition of glycerol.
We identified 16S rRNA gene sequences in sediment samples from Ago Bay in Japan, forming a new branch of the anammox group or closely related to anaerobic ammonium oxidizing (anammox) bacterial sequences. Anammox activity in the sediment samples was detected by 15N tracer assays. These results, along with the results of fluorescence in situ hybridization (FISH) analysis, suggest the presence of anammox bacteria in the marine sediments.
Three hundred sixty-six Aspergillus strains preserved at the National Institute of Technology and Evaluation (NITE) were compared as to phylogenetic relationships (11 species-clusters) based on the DNA sequences of the D1/D2 domains of LSU rRNA and ITS regions, including the 5.8S rRNA and biological activities of their secondary metabolites. The results showed relatively well correlation between the phylogenetic distribution and the production of bioactive compounds, especially, antimicrobial activities.
Staphylococcus hominis KQU-131, isolated from Thai fermented marine fish, produces a heat stable bacteriocin. Structural and genetic analysis indicated that the bacteriocin is a variant of nukacin ISK-1, a type-A(II) lantibiotic, and we termed the bacteriocin nukacin KQU-131. There were three different amino acid residues between nukacin ISK-1 and nukacin KQU-131, one residue in the leader peptide and the other two in the mature peptide.