Comparison of kinetic properties of a hydrophilic form of acetylcholinesterase purified from strains susceptible and resistant to carbamate and organophosphorus insecticides of green rice leafhopper (Nephotettix cincticeps Uhler)     

Yohei Kato 《Pesticide biochemistry and physiology》2004,79(2):64-73

A hydrophilic form of acetylcholinesterase (AChE) was purified from N-methyl carbamate susceptible (SA) and highly N-methyl carbamate-resistant (N3D) strains of the green rice leafhopper (GRLH), Nephotettix cincticeps Uhler. Both of purified AChE from SA and N3D strains displayed the highest activities toward acetylthiocholine (ATCh) at pH 8.5. In the SA strain, the optimum concentrations for ATCh, propionylthiocholine (PTCh), and butyrylthiocholine (BTCh) were about 1 × 10⁻³, 2.5 × 10⁻³, and 1 × 10⁻³ M, respectively. However, in the N3D strain, substrate inhibition was not identified for ATCh, PTCh, and BTCh to 1 × 10⁻² M. The K_m value in the SA strain was 51.1, 39.1, and 41.6 μM and that in the N3D strain was 91.8, 88.1, and 85.2 μM for ATCh, PTCh, and BTCh, respectively. The K_m value in the N3D strain indicated about 1.80-, 2.25-, and 2.05-fold lower affinity than that of the SA strain for ATCh, PTCh, and BTCh, respectively. The V_max value in the SA strain was 70.2, 30.5, and 4.6 U/mg protein and that in the N3D strain was 123.0, 27.0, and 14.5 U/mg protein for ATCh, PTCh, and BTCh, respectively. The V_max value in the N3D strain was 1.75- and 3.15-fold higher for ATCh and BTCh than that in the N3D strain. However, it was 1.13-fold lower for PTCh. The increased activity of AChE in the N3D strain is due to the qualitatively modified enzyme with a higher catalytic efficiency. The bimolecular rate constant (k_i) for propoxur was 27.1 × 10⁴ and 0.51 × 10⁴ M⁻¹ min⁻¹ in the SA and N3D strain and that for monocrotophos was 0.031 × 10⁴ and 2.0 × 10⁴ M⁻¹ min⁻¹ in the SA and N3D strain. AChE from the N3D strain was 53-fold less sensitive than SA strain to inhibition by propoxur. In contrast, AChE from the N3D strain was 65-fold more sensitive to inhibition by monocrotophos than AChE from the SA strain. This indicated negatively correlated cross-insensitivity of AChE to propoxur and monocrotophos.  相似文献   

Leak detection by monitoring pressure to preserve integrity of agricultural pipe     

Asada  Yohei  Kimura  Masaomi  Azechi  Issaku  Iida  Toshiaki  Kubo  Naritaka 《Paddy and Water Environment》2019,17(3):351-358

Paddy and Water Environment - Leakage of agricultural pipes has been increasingly frequent problems due to corrosion, loosening of joints, and cracks, which result in the subsidence of peripheral...  相似文献   

Sequence and unique phylogeny of G genes of bovine respiratory syncytial viruses circulating in Japan     

Asuka Kumagai  Kyoko Kawauchi  Kiyohiko Andoh  Shinichi Hatama 《Journal of veterinary diagnostic investigation》2021,33(1):162

Bovine respiratory syncytial virus (BRSV) is an etiologic agent of bovine respiratory disease. The rapid evolutionary rate of BRSV contributes to genetic and antigenic heterogeneity of field strains and causes occasional vaccine failure. We conducted molecular epidemiologic characterization of BRSV circulating in Japan to obtain genetic information for vaccine-based disease control. Phylogenetic analysis of G and F gene sequences revealed that all of the isolated Japanese BRSV strains clustered in the same genetic subgroup, which was distinct from the 9 known groups. We assigned the Japanese group to subgenotype X. The Japanese isolates formed 2 temporal clusters: isolates from 2003 to 2005 clustered in lineage A; isolates from 2017 to 2019 formed lineage B. The alignment of the deduced amino acid sequences of the G gene revealed that the central hydrophobic region responsible for viral antigenicity is conserved in all of the isolates; unique amino acid mutations were found mainly in mucin-like regions. Our results suggest that BRSV has evolved uniquely in Japan to form the new subgenotype X; the antigenic homogeneity of the viruses within this group is inferred.  相似文献   

Identification of the core rumen bacterial taxa and their population dynamics during the fattening period in Japanese Black cattle     

Hiroto Miura  Takuya Hashimoto  Yukiko Kawanishi  Hiroki Kawauchi  Ryo Inoue  Noriaki Shoji  Kunihiko Saito  Mario Sekiya  Yosuke Saito  Jumpei Yasuda  Chiemi Yonezawa  Tetsushiro Endo  Hirotaka Kasuya  Yutaka Suzuki  Yasuo Kobayashi  Satoshi Koike 《Animal Science Journal》2021,92(1):e13601

The rumen microbiota comprises a vast range of bacterial taxa, which may affect the production of high-quality meat in Japanese Black cattle. The aim of this study was to identify core rumen microbiota in rumen fluid samples collected from 74 Japanese Black cattle raised under different dietary conditions using 16S rRNA gene amplicon sequencing. In the rumen of fattening Japanese Black cattle, 10 bacterial taxa, showing >1% average relative abundance and >95% prevalence, irrespective of the dietary conditions and the fattening periods, were identified as the core rumen bacterial taxa, which accounted for approximately 80% of the rumen microbiota in Japanese Black cattle. Additionally, population dynamics of the core rumen bacterial taxa revealed two distinct patterns: Prevotella spp. and unclassified Bacteroidales decreased in the mid-fattening period, whereas unclassified Clostridiales, unclassified Ruminococcaceae, Ruminococcus spp., and unclassified Christensenellaceae increased during the same period. Therefore, the present study reports the wide distribution of the core rumen bacterial taxa in Japanese Black cattle, and the complementary nature of the population dynamics of these core taxa, which may ensure stable rumen fermentation during the fattening period.  相似文献   

Ability of salmon growth hormone to accelerate somatic growth of juvenil abalone Haliotis discus hannai     

Shunsuke Moriyama  Katsuo Tashiro  Suehiro Furukawa  Hiroshi Kawauchi 《Fisheries Science》2008,74(4):860-866

ABSTRACT:   The ability of salmon growth hormone (sGH) to accelerate the somatic growth of juvenile abalone Haliotis discus hannai by immersion was examined. After immersion for one hour into a sGH-rich solution at a concentration of 30 mg/L, the sGH immunoreactivity in the body fluid of abalone was maximal after one day, and levels were still detectable at two days. No immunoreactivity was observed in the control group. Following immersion for one hour at one or two-week intervals for 120 weeks into the sGH-rich solution at 30 mg/L, the sGH-immersed abalone exhibited a significant increase in shell length and body weight. On the other hand, abalone immersed into a salmon prolactin (sPRL)-rich solution at 30 mg/L for one hour showed a lower increase in both shell length and body weight than the sGH-immersed abalone. No increases in shell length and body weight were observed in either the bovine serum albumin-immersed abalone or untreated controls. These results provide evidence that sGH can be transported from ambient water into the circulatory system of abalone, and can subsequently improve the somatic growth of juveniles.  相似文献   

Identification of cDNA for the HSPA2, HSPA5 and HSPA8 orthologs of the heat shock protein 70 family from guinea fowl (Numida meleagris)     

Shigehisa IWAMOTO  Yohei KOIKE  Kazuyoshi HOSOMICHI  Hiromi HARA  Yutaka YOSHIDA  Hiroshi OGAWA  Kei HANZAWA 《Animal Science Journal》2005,76(5):519-524

  相似文献   

Medication control of flunixin in racing horses: Possible detection times using Monte Carlo simulations     

Taisuke Kuroda  Yohei Minamijima  Motoi Nomura  Shozo Yamashita  Masayuki Yamada  Shunichi Nagata  Hiroshi Mita  Norihisa Tamura  Kentaro Fukuda  Atsutoshi Kuwano  Kanichi Kusano  Pierre-Louis Toutain  Fumio Sato 《Equine veterinary journal》2022,54(5):979-988

  相似文献   

The duality of teleost gonadotropins   总被引：5，自引：0，他引：5  

Hiroshi Kawauchi  Kunimasa Suzuki  Hiromichi Itoh  Penny Swanson  Nobuko Naito  Yoshitaka Nagahama  Masumi Nozaki  Yasumitu Nakai  Seiga Itoh 《Fish physiology and biochemistry》1989,7(1-6):29-38

The duality of salmon gonadotropins has been proved by biochemical, biological, and immunological characterization of two chemically distinc gonadotropins. GTH I and GTH II were equipotent in stimulating estradiol production, whereas GTH II appears to be more potent in stimulating maturational steroid synthesis. The ratio of plasma levels and pituitary contents of GTHs and the secretory control by a GnRH suggest that GTH I is the predominant GTH during vitellogenesis and early stages of spermatogenesis in salmonids, whereas GTH II is predominant at the time of spermiation and ovulation. GTH I and GTH II are found in distinctly separate cells. In trout, GTH I is expressed first in ontogeny, whereas GTH II cells appear coincident with the onset of spermatogenesis and vitellogenesis, and increase dramatically at the time of final reproductive maturation. Comparison of the amino acid sequences of polypeptides and the base sequences of cDNA revealed that salmon GTH I β is more similar to bovine FSHβ than bovine LHβ and salmon GTH II β shows higher homology to bovine LHβ than to bovine FSHβ. The existence of two pituitary gonadotropins in teleosts as well as tetrapods suggests that the divergence of the GTH gene took place earlier than the time of divergence of teleosts from the main line of evolution leading to tetrapods.  相似文献   

Salmon gonadotropes secrete free form alpha (α)-subunit: quantitative analysis by the sandwich cell immunoblot assay     

N. Naito  Y. Koide  T. Yada  T. Azuma  H. Kawauchi 《Fish physiology and biochemistry》2003,28(1-4):103-108

The sandwich cell immunoblot assay confirmed that salmon LH-cells secreted the free form α-subunit along with the dimeric LH, but lower in amounts than the LH.  相似文献   

Regulation of Tenomodulin Expression Via Wnt/β-catenin Signaling in Equine Bone Marrow-derived Mesenchymal Stem Cells     

Shihori MIYABARA  Yohei YUDA  Yoshinori KASASHIMA  Atsutoshi KUWANO  Katsuhiko ARAI 《Journal of Equine Science》2014,25(1):7-13

  相似文献