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Comparison of OspA Serotypes for Borrelia burgdorferi Sensu Lato from Japan,Europe and North America
Toshiyuki Masuzawa Bettina Wilske Tetsuro Komikado Hiroyuki Suzuki Hiroki Kawabata Nanao Sato Koichi Muramatsu Nobutake Sato Emiko Isogai Hiroshi Isogai Russell C. Johnson Yasutake Yanagihara 《Microbiology and immunology》1996,40(8):539-545
Sixty-one Borrelia burgdorferi sensu lato strains from various sources (ticks, human, and wild animals) in Japan and two strains from ticks in Far Eastern Russia were classified on the basis of reactivity with 16 monoclonal antibodies (mAb) to outer surface protein A (OspA) and by DNA-DNA hybridization assay. Eleven OspA serotypes (J1 to J11) were recognized among the Japanese and the Far East Russian isolates (serotypes J1 to J9 were identified as B. garinii, serotype J10 was identified as B. afzelii, and serotype J11 corresponded to B. japonica), whereas 7 OspA serotypes for North American and European isolates previously reported (Bettina Wilske et al, J. Clin. Microbiol. 31:340-350, 1993) were not observed except for OspA serotype 2 which showed identical reactivity with OspA serotype J10. This finding provides helpful information for understanding the geographical distribution of Lyme disease borrelia and the development of vaccine and diagnostic tests. In conclusion: 1. B. burgdorferi sensu stricto has not been observed in Japan, 2. Japanese B. afzelii isolates are closely related to those from Europe, 3. B. garinii isolates from Japan are highly heterogeneous and apparently different from European B. garinii isolates. 相似文献
13.
Il-Kuk Chang Atsushi Tajima Tateki Chikamune Tadao Ohno 《Cell biology international》1995,19(2):143-150
Fluorescent reagent-labelled PGCs isolated from the blood of 2-day-old chick embryos were cultured on stroma cells derived from 5-day-old germinal ridge in Medium 199 supplemented with 10% FBS, human IGF-1, bovine FGF-b, and murine LIF. In 7 experiments, the number of MCs increased by an average of 4.8 fold in 4 days. Intrinsic PGCs in the 5-day embryonic germinal ridge were observed loosely attached to the stroma cells, and they also increased 3.8 fold during culture for 4 days. These results indicate the possibility of applying this culture method to the production of transgenic chickens. 相似文献
14.
Tatsuo Omata Xanja Andriesse Atsushi Hirano 《Molecular & general genetics : MGG》1993,236(2-3):193-202
Summary The nrtA gene, which has been proposed to be involved in nitrate transport of Synechococcus sp. PCC7942 (Anacystis nidulans R2), was mapped at 3.9 kb upstream of the nitrate reductase gene, narB. Three closely linked genes (designated nrtB, nrtC, and nrtD), which encode proteins of 279, 659, and 274 amino acids, respectively, were found between the nrtA and narB genes. NrtB is a hydrophobic protein having structural similarity to the integral membrane components of bacterial transport systems that are dependent on periplasmic substrate-binding proteins. The N-terminal portion of NrtC (amino acid residues 1–254) and NrtD are 58% identical to each other in their amino acid sequences, and resemble the ATP-binding components of binding protein-dependent transport systems. The C-terminal portion of NrtC is 30% identical to NrtA. Mutants constructed by interrupting each of nrtB and nrtC were unable to grow on nitrate, and the nrtD mutant required high concentration of nitrate for growth. The rate of nitrate-dependent O2 evolution (photosynthetic O2 evolution coupled to nitrate reduction) in wild-type cells measured in the presence of l-methionine d,l-sulfoximine and glycolaldehyde showed a dual-phase relationship with nitrate concentration. It followed saturation kinetics up to 10 mM nitrate (the concentration required for half-saturation = 1 M), and the reaction rate then increased above the saturation level of the first phase as the nitrate concentration increased. The high-affinity phase of nitrate-dependent O2 evolution was absent in the nrtD mutant. The results suggest that there are two independent mechanisms of nitrate uptake and that the nrtB-nrtC-nrtD cluster encodes a high-affinity nitrate transport system. 相似文献
15.
Sakamoto Atsushi; Ohsuga Hiroyuki; Wakaura Makoto; Mitsukawa Norihiro; Hibino Takashi; Masumura Takehiro; Sasaki Yukiko; Tanaka Kunisuke 《Plant & cell physiology》1993,34(6):965-968
A cDNA clone for copper/zinc-superoxide dismutase (Cu/Zn-SOD)was isolated from spinach (Spinacia oleracea L.) leaves. Itsnucleotide sequence showed that it codes for a precursor polypeptideof 222 amino acids, including the NH2-terminal 68-residue extensionwhich corresponds to a plastidic transit peptide. Northern hybridization,using plastidic and cytosolic Cu/Zn-SOD cDNAs as the probes,revealed that these two genes are differentially expressed inthe roots and leaves of spinach.
1Present address: Department of Biochemistry and Microbiology,Cook College, Rutgers University New Brunswick, NJ 08903-0231,U.S.A. 相似文献
16.
Hydrogen peroxide formed during the course of the copper(II)-catalysed oxidation of cysteamine with oxygen was continuously determined by a peroxidase (POD)-catalysed luminol chemiluminescence (CL) method. Horseradish peroxidase (HRP), lactoperoxidase (LPO) and Arthromyces ramosus peroxidase (ARP) were used as a CL catalyst. The respective PODs gave specific CL intensity-time profiles. HRP caused a CL delay, and ARP gave a time-response curve which followed the production rate of H2O2. LPO gave only a weak CL flash which decayed promptly. These differences of CL response curves could be explained in terms of the different reactivities of PODs for superoxide anion and the different formation rate of luminol radicals in the peroxidation of luminol catalysed by POD. 相似文献
17.
Histological studies on male sterility of hybrids between laboratory and wild mouse strains 总被引:1,自引:0,他引:1
Atsushi Yoshiki Kazuo Moriwaki Teruyo Sakakura Moriaki Kusakabe 《Development, growth & differentiation》1993,35(3):271-281
In this study the cellular mechanisms of male sterility in F1 hybrids (BNF1) between BALB/c and wild-derived M.MUS-NJL (NJL) was investigated. Cell proliferation and differentiation in the sterile testis were examined by bromodeoxyuridine-labeling and use of germ cell stage-specific antibodies. In BNF1 testes, spermatogonia actively proliferated with a seminiferous epithelial cycle, and were retained in the basal layer of the tubules. However, preleptotene, leptotene and zygotene spermatocytes moved to the adluminal region. Immunohistological data with germ cell stage-specific antibodies indicated the presence of few, if any, pachytene spermatocytes in BNF1 testes. Thus, spermatogenesis seemed to be blocked at the zygotene stage. For examination of germ cell-Sertoli cell interactions, testes of aggregation chimeras between BNF1 and C3H/HeN were analyzed immunohistologically with C3H-specific antibody. Results showed that spermatogenesis of C3H-germ cells was normal, even when these cells in contact with BNF1-Sertoli cells. Differentiation of BNF1-germ cells progressed from zygotene to pachytene stage spermatocytes when these cells were surrounded by C3H-Sertoli cells, but never proceeded beyond the pachytene stage. These observations suggest that at least two different cellular factors may be involved in spermatogenesis, one acting in the germ cells and the other mediated by Sertoli cells. Furthermore, mating experiments revealed that the degree of spermatogenesis varied in different F1 hybrids, and that the major sterility factor was closely linked to the T -locus on chromosome 17. 相似文献
18.
Tokuo Ogawa Junichi Sugenoya Norikazu Ohnishi Keiko Natsume Kazuno Imai Yoshikazu Kandori Akira Ishizuka Atsushi Osada 《European journal of applied physiology and occupational physiology》1993,67(4):354-359
We have examined the nonparallel changes in tampanic membrane temperatures (T
ty) from the two ears in response to various changes in body and head positions. Upon assuming a lateral recumbent position, the T
ty on the lower side increased while that on the upper side decreased. Pressure application over a wide area of the lateral chest only caused inconsistent and obscure asymmetric changes in T
ty. A lateral flexion of the head with the subject sitting upright and a rotation of the head to the side in a supine position induced an increase in the T
ty on the lower side compared to that on the upper side. The temperature and blood flow of the forehead often decreased on the lower side and increased on the upper side, although such responses were not always concomitant with the asymmetric changes in T
ty. A dorsal flexion of the head with the subject in a reclining position caused a slight increase in the T
ty, whereas raising the head upright induced a slight decrease in them. Two additional experiments were carried out with single photon emission computed tomography using 99mTc-hexamethylpropyleneamine oxime as tracer, and a slight, relative decrease in counts was noted in the right hemisphere during rotation of the head to the right. These results would strongly suggest that unilateral increases and decreases in T
ty could have been caused by one-sided decreases and increases, respectively, in blood flow to the brain and/or the tympanic membrane, induced by a vasomotor reflex involving vestibular stimulation. 相似文献
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