Sequence variation of bovine prion protein gene in Japanese cattle (Holstein and Japanese Black)   总被引：3，自引：0，他引：3  

Nakamitsu S  Miyazawa T  Horiuchi M  Onoe S  Ohoba Y  Kitagawa H  Ishiguro N 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(1):27-33

To assess relationships between nucleotide polymorphisms of the prion protein (PRNP) gene and susceptibility to bovine spongiform encephalopathy (BSE), we investigated polymorphisms in the open reading frame (ORF) and 2 upper regions of the PRNP gene from 2 Japanese cattle breeds: 863 healthy Holstein cattle, 6 BSE-affected Holstein cattle, and 186 healthy Japanese Black (JB) cattle. In the ORF, we found single-nucleotide polymorphisms (SNPs) at nucleotide positions 234 and 576 and found 5 or 6 copies of the octapeptide repeat, but we did not find any amino acid substitutions. In the upper region, we examined 2 sites of insertion/deletion (indel) polymorphisms: a 23-bp indel in the upper region of exon 1, and a 12-bp indel in the putative promoter region of intron 1. A previous report suggests that the 23-bp indel polymorphism is associated with susceptibility to BSE, but we did not find a difference in allele frequency between healthy and BSE-affected Holstein cattle. There were differences in allele frequency between healthy Holstein and JB cattle at the 23- and 12-bp indels and at the SNPs at nucleotide positions 234 and 576, but there was no difference in allele frequency of the octapeptide repeat. We identified a unique PRNP gene lacking a 288-bp segment (96 amino acids) in DNA samples stocked in our laboratory, but this deletion was not found in any of the 1049 cattle examined in the present study. The present results provide data about variations and distribution of the bovine PRNP gene.  相似文献   

Uptake and transformation of pesticide metabolites by duckweed (Lemna gibba)     

Fujisawa T  Kurosawa M  Katagi T 《Journal of agricultural and food chemistry》2006,54(17):6286-6293

Uptake and transformation of 14C-labeled metabolites from several pesticides, 3-methyl-4-nitrophenol (1), 3,5-dichloroaniline (2), 3-phenoxybenzoic acid (3), (R,S)-2-(4-chlorophenyl)-3-methylbutanoic acid (4), and (1RS)-trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylic acid (5), were examined by using duckweed (Lemna gibba) in Hoagland's medium. More uptake into duckweed from the exposure water at pH 7.0 was observed for non-ionized 1 and 2 than for 3-5 in an ionized form, and their hydrophobicity accounted for these differences. While carboxylic acids 4 and 5 were scarcely transformed in duckweed, 1-3 mainly underwent phase II conjugation with glucose for 1 and 2, malic acid for 3, glutamic acid for 2, and malonylglucose for 3, the chemical identities of which were confirmed by various spectrometric analyses (LC-MS, LC-MS/MS, and NMR) and/or HPLC cochromatography with reference synthetic standards.  相似文献   

Furan-2,5-dimethylene-tethered bis-imidacloprid insecticide conferring high potency     

Kagabu S  Ohno I  Tomizawa M  Durkin KA  Matsuura R  Uchiyama D  Nagae N  Kumazawa S 《Journal of agricultural and food chemistry》2010,58(22):11832-11836

Bis-imidacloprid (bis-IMI) analogues with suitable alkylene spacers have plant-systemic insecticidal properties. The alkylene-tethered bis-IMI binds in a unique mode to the insect nicotinic acetylcholine receptor (nAChR) wherein the chloropyridine moieties are embraced by two distinct and distant domains. The heptamethylene spacer optimally bridges these two subsites, yet the linker itself binds in a relatively nonspecific manner. This investigation examines the hypothesis that a bis-IMI analogue with a heteroaromatic tether, which undergoes specific interaction(s) with the newly recognized receptor cavity, may enhance the potency relative to those of the alkylene-tethered derivatives. Remarkably, a novel bis-IMI with a furan-2,5-dimethylene fulcrum showed highest receptor potency and insecticidal activity among the analogues with various chemotype spacers. The nAChR structural model, simulating the binding site interactions of the furan-2,5-dimethylene-tethered bis-IMI, reveals that the furan ring is nestled in a hydrophobic pocket, consisting of three aromatic amino acids, and is stabilized via hydrogen bonding.  相似文献   

Surface plasmon resonance analysis on interactions of food components with a taste epithelial cell model     

Miyano M  Yamashita H  Sakurai T  Nakajima K  Ito K  Misaka T  Ishimaru Y  Abe K  Asakura T 《Journal of agricultural and food chemistry》2010,58(22):11870-11875

A new device for evaluating the continuity of taste was developed with the use of surface plasmon resonance (SPR). The model of lingual cells was constructed with liposomes immobilized onto an L1 sensor chip for SPR. Using this device, we classified food components into three categories according to the sensorgram pattern and residual ratio on lipid bilayer. Samples in group A strongly interacted with lipid bilayer, those in group B poorly interacted, and those in group C belong to neither group A nor group B. Sweet proteins and gymnemic acids that prolonged sweet perception were categorized in group A. Almost all the carbohydrates investigated and aspartame, of which the taste perception does not continue, belonged to group B. This device made it possible to detect the interaction with lipid bilayer and dissected the mechanism of taste continuity.  相似文献   

Nereistoxin and cartap neurotoxicity attributable to direct block of the insect nicotinic receptor/channel     

Lee SJ  Tomizawa M  Casida JE 《Journal of agricultural and food chemistry》2003,51(9):2646-2652

Nereistoxin (NTX) (4-dimethylamino-1,2-dithiolane) is the naturally occurring prototype for cartap [the bis(thiocarbamate) derivative of the NTX dithiol], which is generally regarded as a proinsecticide reverting to NTX. The aim of this study is to define the target site(s) for dithiolanes and dithiol esters. The affinity of [(3)H]NTX was not suitable for binding assays with honeybee (Apis mellifera) head membranes. However, NTX and cartap are equally potent, direct-acting, and competitive displacers of [(3)H]thienylcyclohexylpiperidine binding at the noncompetitive blocker (NCB) site of the Apis nicotinic acetylcholine receptor (nAChR)/channel. NTX also binds at the Apis [(3)H]imidacloprid agonist site, but cartap does not. As candidate metabolic pathways, sequential N-desmethylation and S-oxidation of NTX progressively reduce its potency at the NCB site and toxicity to houseflies. A P450 inhibitor reduces the toxicity of NTX and enhances it with cartap. Surprisingly, cartap is not just a pro-NTX but instead directly induces inhibitory neurotoxicity by blocking the nAChR/channel, whereas NTX may have dual NCB and agonist targets.  相似文献   

The response of collembolan community to the amount and composition of organic matter of a forest floor: Proceedings of the Xth international Colloquium on Apterygota, České Budějovice 2000: Apterygota at the Beginning of the Third Millennium     

Motohiro Hasegawa   《Pedobiologia》2002,46(3-4)

  相似文献   

Identification of distinctive volatile compounds in fish sauce   总被引：9，自引：0，他引：9  

Fukami K  Ishiyama S  Yaguramaki H  Masuzawa T  Nabeta Y  Endo K  Shimoda M 《Journal of agricultural and food chemistry》2002,50(19):5412-5416

  相似文献   

The relationship between the organic matter composition of a forest floor and the structure of a soil arthropod community     

Motohiro Hasegawa   《European Journal of Soil Biology》2001,37(4)

The relationship between the amount and conposition of organic matter of a forest floor and the structure of the soil arthropod community was investigated in a temperate mixed forest of beech and pine trees. Seven enivronmental variables, i.e. broad leaves, pine needles, twigs, roots, others, total organic matter (sum of broad leaves, pine needles, twigs and others) and water content, were related to the soil arthropods in the statistical analysis. Pearson correlation was used to analyze the relation between environmental variables and total abundance of Collembola, Oribatida and Mesostigmata. Total abundance of Collembola and Oribatida did not show a clear correlation with total organic matter. Total abundance of Mesostigmata showed the positive correlation with broad leaves or total organic matter. The result in this study might be due to the fact that ‘organic matter’ treated in this study was the material which was left on the 2 mm mesh sieve, and most of small fragmental organic matter in the F or H layer was not included. Canonical correspondence analysis (CCA) was used to relate the variables of the organic matter to the community organizations of Collembola and Oribatida. CCA ordination indicated that the total amount of organic matter was the most important variable for the organization of both communities. These results suggest that the amount and composition of organic matter influenced the community organization of soil arthropods in a mixed forest.  相似文献   

Natural antibiotic function of a human gastric mucin against Helicobacter pylori infection     

Kawakubo M  Ito Y  Okimura Y  Kobayashi M  Sakura K  Kasama S  Fukuda MN  Fukuda M  Katsuyama T  Nakayama J 《Science (New York, N.Y.)》2004,305(5686):1003-1006

Helicobacter pylori infects the stomachs of nearly a half the human population, yet most infected individuals remain asymptomatic, which suggests that there is a host defense against this bacterium. Because H. pylori is rarely found in deeper portions of the gastric mucosa, where O-glycans are expressed that have terminal alpha1,4-linked N-acetylglucosamine, we tested whether these O-glycans might affect H. pylori growth. Here, we report that these O-glycans have antimicrobial activity against H. pylori, inhibiting its biosynthesis of cholesteryl-alpha-D-glucopyranoside, a major cell wall component. Thus, the unique O-glycans in gastric mucin appeared to function as a natural antibiotic, protecting the host from H. pylori infection.  相似文献   

Requirement of phospholipase Cdelta4 for the zona pellucida-induced acrosome reaction     

Fukami K  Nakao K  Inoue T  Kataoka Y  Kurokawa M  Fissore RA  Nakamura K  Katsuki M  Mikoshiba K  Yoshida N  Takenawa T 《Science (New York, N.Y.)》2001,292(5518):920-923

Several phospholipase C (PLC) isoforms have been found in male and female mammalian gametes, and splicing isoforms of PLCdelta4 are predominantly expressed in testis. Here we report that male mice in which the PLCdelta4 gene had been disrupted either produced few small litters or were sterile. In vitro fertilization studies showed that insemination with PLCdelta4-/- sperm resulted in significantly fewer eggs becoming activated and that the calcium transients associated with fertilization were absent or delayed. PLCdelta4-/- sperm were unable to initiate the acrosome reaction, an exocytotic event required for fertilization and induced by interaction with the egg coat, the zona pellucida. These data demonstrate that PLCdelta4 functions in the acrosome reaction that is induced by the zona pellucida during mammalian fertilization.  相似文献