Biomedical subjects

Yoko Takahashi

Publications and source records attributed to Yoko Takahashi.

At least 19 recordsLinked to original sources

PubMed2007

17beta-Estradiol differentially regulates androgen-responsive genes through estrogen receptor-beta- and extracellular-signal regulated kinase-dependent pathways in LNCaP human prostate cancer cells.

The molecular mechanism underlying the actions of estrogens in normal prostate physiology and prostate cancer development remains unclear. In the present study we tested the hypothesis that estrogens modulate androgen-dependent events in prostate cells by examining the effects of 17beta-estradiol (E2) on androgen-responsive genes (ARGs) in the androgenresponsive LNCaP cells. We found that LNCaP cells express estrogen receptor-beta (ER-beta) as the major form of ER and ER treatment with E2 led to an increase in cell growth. The proliferative effect of E2 correlated with induction of several ARGs by E2. Interestingly, some other ARGs did not respond to E2. Consistent with involvement of ER-beta, the induction of both cell growth and ARG mRNA levels by E2 was attenuated by the pure antiestrogen ICI 182,780. Moreover, we found ER-beta small interfering RNA attenuated induction of ARG mRNAs by E2. However, the effect of E2 on ARG mRNA appeared also to require the androgen receptor and to be mediated through activation of the extracellular-signal regulated kinase (ERK) pathway. These results provide mechanistic evidence supporting a direct effect of estrogen, mediated through ER-beta- and ERK-dependent pathways, on specific molecular targets in human prostate cancer cells.

Androgens↗

PubMed2007

Comparative analysis of sesame lignans (sesamin and sesamolin) in affecting hepatic fatty acid metabolism in rats.

Effects of sesamin and sesamolin (sesame lignans) on hepatic fatty acid metabolism were compared in rats. Rats were fed either a lignan-free diet, a diet containing 0.6 or 2 g/kg lignan (sesamin or sesamolin), or a diet containing both sesamin (1.4 g/kg) and sesamolin (0.6 g/kg) for 10 d. Sesamin and sesamolin dose-dependently increased the activity and mRNA abundance of various enzymes involved in hepatic fatty acid oxidation. The increase was much greater with sesamolin than with sesamin. These lignans increased parameters of hepatic fatty acid oxidation in an additive manner when added simultaneously to an experimental diet. In contrast, they decreased the activity and mRNA abundance of hepatic lipogenic enzymes despite dose-dependent effects not being necessarily obvious. Sesamin and sesamolin were equally effective in lowering parameters of lipogenesis. Sesamolin accumulated in serum at 33- and 46-fold the level of sesamin at dietary concentrations of 0.6 and 2 g/kg, respectively. The amount of sesamolin accumulated in liver was 10- and 7-fold that of sesamin at the respective dietary levels. Sesamolin rather than sesamin can account for the potent physiological effect of sesame seeds in increasing hepatic fatty acid oxidation observed previously. Differences in bioavailability may contribute to the divergent effects of sesamin and sesamolin on hepatic fatty acid oxidation. Sesamin compared to sesamolin was more effective in reducing serum and liver lipid levels despite sesamolin more strongly increasing hepatic fatty acid oxidation.

Animals↗

PubMed2006

HOXD3-overexpression increases integrin alpha v beta 3 expression and deprives E-cadherin while it enhances cell motility in A549 cells.

We have previously shown that transduction of HOXD3, one of homeobox genes, into human lung cancer A549 cells enhances cell motility, invasion and metastasis. In the present study, we examined the roles of integrin beta3 which was up-regulated by HOXD3-overexpression in the HOXD3-induced motility of A549 cells. We first established integrin beta3-transfectants and compared their motile activity to those of the HOXD3-transfected, control-transfected and parental cells by three different assays. The integrin beta3-transfectants as well as the HOXD3-transfectants formed heterodimer with integrin alphav subunit, and showed highly motile activities assessed by haptotaxis or phagokinetic track assay compared to the control transfectants or parental cells. In vitro wound-healing assay revealed that migratory activities were graded as the HOXD3-transfectants > the integrin beta3-transfectants > the control transfectants or parental cells. E-cadherin was expressed in the integrin beta3-transfectants but not expressed in the HOXD3-transfectants. An addition of function-blocking antibody to E-cadherin into the wound-healing assay promoted the migratory activity of the integrin beta3-transfectants, suggesting that E-cadherin prevented the cells from dissociating from the wound edges. These results indicate that increased expression of integrin alphav beta3 and loss of E-cadherin by HOXD3-overexpression are responsible for the enhanced motility and dissociation.

Animals↗

PubMed2006

Activity and mRNA levels of enzymes involved in hepatic fatty acid oxidation in mice fed citrus flavonoids.

OBJECTIVE: We investigated the physiologic activity of citrus flavonoids, naringenin, and hesperetin in affecting the activity and mRNA levels of enzymes involved in hepatic fatty acid oxidation and serum and liver lipid levels in male ICR mice. METHODS: Six-week-old male ICR mice were fed experimental diets containing 1% naringenin or hesperetin and a control diet free of citrus flavonoids for 21 d. RESULTS: Naringenin caused a significant 56.1% increase in the hepatic cyanide-insensitive palmitoyl-coenzyme A oxidation rate. This compound also caused significant increases ranging from 9.8% to 55.6% in activity levels of various enzymes involved in hepatic fatty acid oxidation. These increases were accompanied by upregulation of gene expression of enzymes involved in peroxisomal fatty acid oxidation including increases of 46.8% to 88.7% of carnitine octanoyltransferase, acyl-coenzyme A oxidase, bifunctional enzyme, and 3-ketoacyl-coenzyme A thiolase. Messenger RNA levels of mitochondrial proteins involved in fatty acid oxidation except for trifunctional enzyme subunit-beta were not affected by naringenin. Naringenin also significantly increased more than five-fold the mRNA level of microsomal cytochrome P-450 IV A1 involved in omega-oxidation of fatty acids. However, hesperetin did not affect any parameter of hepatic fatty acid oxidation. Naringenin, but not hesperetin, significantly lowered serum levels of triacylglycerol, cholesterol, phospholipids, and free fatty acid. CONCLUSION: We demonstrated that naringenin has the physiologic effect of increasing hepatic fatty acid oxidation through upregulation of gene expression of enzymes involved in peroxisomal beta-oxidation in mice. The change may account for the propensity of this compound to lower serum lipid levels.

Animals↗

PubMed2006

PTEN tumor suppressor associates with NHERF proteins to attenuate PDGF receptor signaling.

PTEN, a tumor suppressor frequently inactivated in many human cancers, directly antagonizes the activity of phosphatidylinositol-3-OH kinase (PI3K) by dephosphorylating phosphoinositides. We show here that PTEN interacts directly with the NHERF1 and NHERF2 (Na+/H+ exchanger regulatory factor) homologous adaptor proteins through the PDZ motif of PTEN and the PDZ1 domain of NHERF1 or both PDZ domains of NHERF2. NHERFs were shown to interact directly with platelet-derived growth factor receptor (PDGFR), and we demonstrate the assembly of a ternary complex between PTEN, NHERFs and PDGFR. The activation of the PI3K pathway after PDGFR stimulation was prolonged in NHERF1(-/-) mouse embryonic fibroblasts as compared to wild-type cells, consistent with defective PTEN recruitment to PDGFR in the absence of NHERF1. Depletion of NHERF2 by small interfering RNA similarly increased PI3K signaling. Phenotypically, the loss of NHERF1 enhanced the PDGF-induced cytoskeletal rearrangements and chemotactic migration of the cells. These data indicate that, in normal cells, NHERF proteins recruit PTEN to PDGFR to restrict the activation of the PI3K.

Animals↗

PubMed2006

Genistein affects androgen-responsive genes through both androgen- and estrogen-induced signaling pathways.

This study examined the mechanisms by which the prostate cancer chemopreventive agent genistein modulates gene expression in LNCaP human prostate cancer cells. Expression of androgen- and estrogen-regulated genes was measured in LNCaP cells cultured in the presence or absence of hormonal stimulation and the presence or absence of genistein. Genistein strongly suppressed basal expression of androgen-responsive gene (ARG) mRNAs, including prostate-specific antigen (PSA) and Ste20-related proline-alanine-rich kinase (SPAK). However, genistein had little or no effect on basal expression of two other ARGs, beta2-microglobulin (B2M) or selenoprotein P (SEPP1). Culturing LNCaP cells in the presence of the synthetic androgen R1881-induced increases in PSA, SPAK, B2M, and SEPP1 mRNA levels. The R1881-induced expression of these genes was uniformly blocked by genistein. For PSA and SPAK, genistein also blocked or downregulated 17beta-estradiol-induced increases in mRNA expression. These results indicate that genistein selectively alters expression of ARG mRNAs in LNCaP cells through modulation of both androgen- and estrogen-induced signaling pathways.

Androgens↗

PubMed2006

Molecular signatures of soy-derived phytochemicals in androgen-responsive prostate cancer cells: a comparison study using DNA microarray.

The present study utilized microarray technology as a tool to elucidate the molecular signatures of soy-derived phytochemicals in the human androgen-responsive prostate cancer cell line LNCaP. Global gene expression pattern analysis of LNCaP cells exposed to 0, 1, 5, or 25 microM of the soy-derived phytochemicals equol and daidzein were conducted and compared. The data were further compared with previously generated data from exposure of LNCaP cells to the same doses of genistein, a soy isoflavone. Multidimensional scaling (MDS) analyses of the expression patterns suggest that these compounds exerted differential effects on gene expression in LNCaP cells. Further examination of specific gene changes revealed that these compounds differentially modulated genes in multiple cellular pathways, including the cell-cycle pathway genes. However, the three compounds also exerted similar effect on genes belonging to several other important cellular pathways. A universal effect of the three compounds on androgen-responsive genes, IGF-1 pathway gene, and MAP kinase-related pathway gene was observed. These results provide the foundation for establishing molecular signatures for equol, daidzein, and genistein. Moreover, these results also allow for the identification of candidate mechanism(s) by which soy phytochemicals and soy may act in prostate cancer cells.

Androgens↗

PubMed2006

Dietary sesamin and docosahexaenoic and eicosapentaenoic acids synergistically increase the gene expression of enzymes involved in hepatic peroxisomal fatty acid oxidation in rats.

The interaction of sesamin, one of the most abundant lignans in sesame seed, and highly purified docosahexaenoic acid (DHA) or eicosapentaenoic acid (EPA) in the form of ethyl ester in affecting hepatic fatty acid oxidation was examined in rats. In the first experiment, 3 groups of rats were fed with purified experimental diets free of n-3 fatty acid ethyl ester and containing 0%, 0.2%, and 0.4% sesamin (1:1 mixture of sesamin and episesamin), and 2 groups of animals were fed with a 2% DHA ethyl ester diet containing either 0% or 0.2% sesamin. In the second trial, 4 groups of rats were fed with either a 0% or a 2% EPA ethyl ester diet containing 0% or 0.2% sesamin. After 15 days of feeding, DHA and EPA ethyl esters added to a sesamin-free diet little affected the activity and messenger RNA (mRNA) levels of various enzymes involved in fatty acid oxidation. Sesamin increased the activity levels of various hepatic enzymes involved in fatty acid oxidation irrespective of the presence or absence of n-3 fatty acid ethyl ester in diets. However, the diet containing sesamin and DHA or EPA ethyl ester in combination increased many of these parameters synergistically. In particular, the peroxisomal palmitoyl-coenzyme A oxidation rate and acyl-coenzyme A oxidase activity level were much higher in rats fed with sesamin and DHA or EPA in combination than in animals fed with a diet free of n-3 fatty acid ethyl ester and containing sesamin. Analyses of mRNA levels revealed that a diet simultaneously containing sesamin and n-3 fatty acid ethyl ester increased the gene expression of various enzymes involved in peroxisomal fatty acid oxidation in a synergistic manner. However, the combination of sesamin and n-3 fatty acid ethyl esters was ineffective in causing a synergistic increase in mRNA levels of enzymes of mitochondrial fatty acid oxidation, microsomal cytochrome P-450 IV A1, and cytosolic liver-type fatty acid-binding protein. It was concluded that sesamin and DHA or EPA ethyl ester synergistically increased hepatic fatty acid oxidation primarily through up-regulation of the gene expression of peroxisomal fatty acid oxidation enzymes. The results essentially reproduced those observed in our previous study with a diet containing both fish oil and sesamin despite the fact that DHA and EPA ethyl esters were much less effective than fish oil in increasing hepatic fatty acid oxidation.

Animals↗

PubMed2006

Polyunsaturated fats attenuate the dietary phytol-induced increase in hepatic fatty acid oxidation in mice.

The effects of dietary phytol and the type of dietary fat on hepatic fatty acid oxidation were examined in male ICR mice. Mice were fed diets containing 0 or 5 g/kg phytol and 100 g/kg palm, safflower, or fish oil for 21 d. Among the groups fed phytol-free diets, the activities and mRNA abundance of various enzymes involved in fatty acid oxidation were greater in mice fed fish oil than in those fed palm or safflower oil. Dietary phytol profoundly increased the activities and mRNA abundance of hepatic fatty acid oxidation enzymes in mice fed palm oil. However, safflower and fish oils, especially the latter, greatly attenuated the phytol-dependent increase in hepatic fatty acid oxidation. The hepatic concentration of phytanic acid, a metabolite of phytol that is the ligand and activator of retinoid X receptors and peroxisome proliferator-activated receptors, was higher in mice fed fish oil than safflower or palm oil, and in those administered safflower oil than palm oil. The hepatic mRNA abundance of sterol carrier protein-2, a lipid-binding protein involved in phytol metabolism, was inversely correlated with the hepatic concentration of phytanic acid. We demonstrated that polyunsaturated fats attenuate the enhancing effect of dietary phytol on hepatic fatty acid oxidation. Dietary fat-dependent changes in the hepatic phytanic acid concentration cannot account for this phenomenon.

Aldehyde Dehydrogenase↗

PubMed2006

Immunoglobulin preparations attenuate organ dysfunction and hemostatic abnormality by suppressing the production of cytokines in lipopolysaccharide-induced disseminated intravascular coagulation in rats.

OBJECTIVE: We attempted to clarify the effect of immunoglobulin concentrates on the rat lipopolysaccharide (LPS)-induced disseminated intravascular coagulation (DIC) model. DESIGN: Prospective, comparative, experimental study. SETTING: Laboratory at a university hospital. SUBJECTS: Male Wistar rats, aged 6 to 7 wks and weighing 160 to 170 g. INTERVENTIONS: Two kinds of experiments were performed. In the first, experimental DIC was induced by sustained infusion of 30 mg/kg LPS for 4 hrs via the tail vein, and two doses of immunoglobulin (25 or 100 mg/kg/4.5 hrs) were administered to rats 30 mins before infusion of LPS, after which immunoglobulin infusion was continued for a further 4 hrs. In the second, experimental DIC was induced by sustained infusion (5 mg/kg/1 hr) of LPS for 1 hr, and one dose of immunoglobulin (100 mg/kg/4 hrs) was administered to rats after LPS induction. The parameters were estimated at 4 hrs and 8 hrs in the first experiment and at 1, 5, and 10 hrs in the second one. MEASUREMENT AND MAIN RESULTS: Similar results were observed in the two experiments. Consumption coagulopathy and hemostatic activation were attenuated, especially when immunoglobulin was administered before LPS infusion. Plasma levels of creatinine and alanine aminotransferase were significantly depressed by coadministration of immunoglobulin. Marked glomerular fibrin deposition was observed in the LPS-induced DIC model, but this deposition was reduced by immunoglobulin. In the first stage of the experiment, plasma levels of tumor necrosis factor (TNF) and interleukin (IL)-6 were suppressed by coadministration of immunoglobulin. In the second, plasma levels of IL-6 were significantly suppressed by immunoglobulin. CONCLUSION: It was concluded that plasma levels of TNF and IL-6 could be significantly suppressed by immunoglobulin in the LPS-induced DIC model. Moreover, hemostatic abnormality, organ dysfunction, and glomerular fibrin deposition in this model were all ameliorated by immunoglobulin.

Alanine Transaminase↗

PubMed2006

No interplay between the pathways mediating coagulation and inflammation in tissue factor-induced disseminated intravascular coagulation in rats.

OBJECTIVE: Previous reports have suggested an interplay between the pathways mediating coagulation and inflammation in endotoxemia and sepsis. The present study was designed to examine whether cross-signaling between the pathways mediating coagulation and inflammation occurs, as suggested by the pattern of cytokine production observed following tissue-factor (TF)-induced disseminated intravascular coagulation (DIC). DESIGN: Prospective, comparative, experimental study. SETTING: Laboratory at a university hospital. SUBJECTS: Male Wistar rats, aged 6-7 wks, and weighing 160-170 g. INTERVENTIONS: Male Wistar rats were administered TF (3.75 units/kg every 4 hrs), TF, and tranexamic acid (TA; 50 mg/kg every 4.5 hrs) or lipopolysaccharide (30 mg/kg every 4 hrs) via the tail vein, and blood was sampled at 0, 4, 8 and 12 hrs. MEASUREMENTS AND MAIN RESULTS: Subsequent alterations in thrombin-antithrombin complex and fibrinogen levels, as well as platelet counts, indicated that the severity of both types of experimental DIC (TF-induced and lipopolysaccharide-induced) was similar with respect to hemostatic activation and development of consumption coagulopathy. In lipopolysaccharide-induced DIC, a sharp increase in plasma tumor necrosis factor levels was observed at 4 hrs, after which a sharp decline was noted. Plasma levels of interleukin-6 were markedly increased at 4 hrs, after which a sustained elevation was observed for the duration of the experimental period (tumor necrosis factor, 1270 +/- 280, 180 +/- 40, and 120 +/- 30 pg/mL at 4, 8 and 12 hrs, respectively; interleukin-6, 5810 +/- 1320, 4850 +/- 730, and 5230 +/- 1280 pg/mL at 4, 8 and 12 hrs, respectively). On the other hand, tumor necrosis factor and interleukin-6 were not detected following TF-induced DIC (0 +/- 0 at 4, 8, and 12 hrs for both tumor necrosis factor and interleukin-6). In the TF+TA group, significant increases in tumor necrosis factor and interleukin-6 were observed, compared with the TF group. CONCLUSIONS: There is no overt interplay between the pathways mediating coagulation and inflammation in TF-induced DIC, as observed in lipopolysaccharide-induced DIC.

Animals↗

PubMed2006

Microbacterium deminutum sp. nov., Microbacterium pumilum sp. nov. and Microbacterium aoyamense sp. nov.

Three novel bacterial strains were isolated from a soil sample collected in Japan by culture on a GPM agar plate supplemented with superoxide dismutase and catalase. The strains were Gram-positive, catalase-positive, non-motile bacteria with L-ornithine as a diagnostic diamino acid of the peptidoglycan. The acyl type of the peptidoglycan was N-glycolyl. The major menaquinones were MK-12, 13 and 14. Mycolic acids were not detected. G+C contents of the DNA were in the range 69-71 mol%. Comparative 16S rRNA gene sequence analysis revealed that the isolates belonged to the genus Microbacterium and were closely related to Microbacterium terregens, Microbacterium aurum, Microbacterium koreense, Microbacterium schleiferi and Microbacterium lacticum. However, M. aurum, M. koreense and M. lacticum clearly differed from the isolated strains based on the presence of L-lysine as the cell-wall diamino acid and various other chemotaxonomic characteristics. Levels of DNA-DNA relatedness showed that the isolated strains represented three separate genomic species. Based on both phenotypic and genotypic data, the following novel species of the genus Microbacterium are proposed: Microbacterium deminutum sp. nov. (type strain KV-483(T)=NRRL B-24453(T)=NBRC 101278(T)), Microbacterium pumilum sp. nov. (type strain KV-488(T)=NRRL B-24452(T)=NBRC 101279(T)) and Microbacterium aoyamense sp. nov. (type strain KV-492(T)=NRRL B-24451(T)=NBRC 101280(T)).

Actinomycetales↗

PubMed2006

Disordered expression of HOX genes in human non-small cell lung cancer.

We hypothesized that the disordered tissue architecture in cancer results from the cells executing the program designed during ontogeny in a spatio-temporally inappropriate manner. HOX genes are known as master regulators of embryonic morphogenesis, and encode transcription factors which regulate the transcription of the downstream genes to realize the program of body plan. In this study, we quantified the expression levels of 39 HOX genes in 41 human non-small cell lung cancer (non-SCLC) and non-cancerous lung tissues by a comprehensive analysis system based on the real-time RT-PCR method. We found that the expression levels of HOXA1, A5, A10 and C6 in squamous cell carcinoma tissues (and HOXA5 and A10 in adenocarcinoma tissues) were significantly higher than those in the non-cancerous tissues. Comparison of HOX gene expressions between adenocarcinoma and squamous cell carcinoma tissues showed higher expressions of HOXA1, D9, D10 and D11 in squamous cell carcinoma tissues than in adenocarcinoma tissues. Immunohistochemical analysis revealed that HOXA5 and A10 proteins were localized in the cytoplasm of tumor cells in both adenocarcinoma and squamous cell carcinoma tissues. These results suggest that the disordered patterns of HOX gene expressions were involved not only in the development of non-SCLC but also in the histologically aberrant diversity such as adenocarcinoma and squamous cell carcinoma.

Adult↗

PubMed2005

Altered expressions of HOX genes in human cutaneous malignant melanoma.

HOX genes act as master genes to control morphogenesis. In human, HOX genes form 4 clusters composing 9 to 11 HOX genes (39 genes in total) on different chromosomes. We hypothesized that aberrant expression of HOX genes was associated with development and subsequent progression of melanoma and that the 39 HOX gene expression pattern determined the sites where melanoma grew. The expression levels of 39 HOX genes in 15 human cutaneous melanoma specimens and 7 nevus pigmentosus specimens were quantified by a comprehensive analysis system based on the real-time RT-PCR method. We found that the expression levels of HOXA11, A13, B9, D12 and D13 in melanoma were higher than those in nevus pigmentosus and that the expression levels of HOXA11, B2 and C13 were significantly different between pT4 melanoma and pT1 to pT3 melanoma. It was most notable that the expression levels of HOXA1, A2, C4 and B13 in melanoma with distant metastasis were higher than those in melanoma without it. On the other hand, we found no relationship between HOX genes expression patterns and the growing sites of melanoma. These results indicated that the misexpressions of some specific HOX genes were implicated in melanoma genesis and metastasis but had no linkage with melanoma sites.

Adult↗

PubMed2005

The effect of periocular warming on accommodation.

PURPOSE: To investigate the effect of periocular warming on accommodation amplitude and near vision after prolonged near work in visual display terminal (VDT) workers in an office setting. DESIGN: Prospective interventional observational case series. PARTICIPANTS: Ten healthy Japanese male volunteers (mean age, 39.3+/-2 years [range, 36-43]) with a best distance corrected visual acuity (VA) of >20/20 who performed near work for 7 hours were included in the study. MAIN OUTCOME MEASURES: The differences of subjective and objective accommodations, near acuity, and pupil diameters were compared and studied in 2 experimental settings with and without periocular warming. METHODS: Two experiments were performed on each subject on 2 different days. In one experiment, the subjects wore an eye mask and closed their eyelids for 10 minutes after 7 hours of VDT work (lid closure [LC] group). In the other experiment, the subjects applied warming sheets (WSs) to their eyelids and the periocular region and wore masks for 10 minutes again after 7 hours of VDT work (WS group). Visual display terminal work was performed under the same settings on both days. Subjective and objective accommodations, near vision, and pupil diameters were measured immediately before and immediately after the resting or warming procedure and again 90 minutes after the resting or warming procedures. RESULTS: Fifty percent of eyes had an increase in the accommodation amplitude of at least 0.5 diopters immediately after application of the WSs. Forty percent of eyes still maintained the accommodation amplitude level at 90 minutes. The mean near logarithm of the minimum angle of resolution VA immediately after application of WSs and at 90 minutes significantly improved relative to the near acuity values after simple eyelid closure. CONCLUSION: Periocular warming was found to be associated with increases in subjective and objective accommodations, with a concomitant improvement in near VA. Periocular warming with disposable WSs is a simple and effective method of increasing near work-related ergonomy.

Accommodation, Ocular↗

PubMed2005

A new antibiotic, antimycin Ag, produced by Streptomyces sp. K01-0031.

A new antimycin group antibiotic, antimycin A9, was isolated from a cultured broth of Streptomyces sp. K01-0031 together with antimycins A3a, A3b, A4, and A7, and flazin methyl ester. Antimycin A9 is the first antimycin having an aromatic 8-acyl residue. It showed potent nematocidal and insecticidal activities against Caenorhabditis elegans and Artemia salina, respectively. It inhibited bovine heart NADH oxidase at nanomolar level like other known antimycins.

Animals↗

PubMed2005

Phenatic acids A and B, new potentiators of antifungal miconazole activity produced by Streptomyces sp. K03-0132.

Two new phenols, designated phenatic acids A and B, were isolated along with known actiphenol, from the culture of Streptomyces sp. K03-0132 by solvent extraction, silica gel column chromatography and HPLC. Their structures were elucidated by spectroscopic analyses including mainly various NMR experiments. They have a common 1-hydroxy 2, 4-dimethyl benzene ring. These compounds potentiate miconazole activity against Candida albicans. Phenatic acid B also showed moderate antimicrobial activity against Bacillus subtilis, Staphylococcus aureus, Bacteroides fragilis and Acholeplasma laidlawii.

Acetates↗

PubMed2005

Oryzihumus leptocrescens gen. nov., sp. nov.

Three novel strains were isolated from a soil sample collected in Japan using GPM agar plates supplemented with superoxide dismutase and/or catalase. The strains were Gram-positive, catalase-positive, irregular rod-shaped bacteria with meso-diaminopimelic acid as a peptidoglycan diagnostic diamino acid, and the acyl type of the peptidoglycan was acetyl. The major menaquinone was MK-8(H4). Mycolic acids were not detected. The G+C content of the DNA was 72-73 mol%. On the basis of morphological and chemotaxonomic properties and a phylogenetic analysis using 16S rRNA gene sequences, these strains were classified as a novel genus and species, Oryzihumus leptocrescens gen. nov., sp. nov., in the family Intrasporangiaceae of the order Actinomycetales. The type strain is KV-628T (=NRRL B-24347T=JCM 12835T=NBRC 100762T).

Actinomycetales↗