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301.
N-Acetylgalactosamine 4-sulfate 6-O-sulfotransferase (GalNAc4S-6ST) transfers sulfate to position 6 of GalNAc(4SO(4)) residues in chondroitin sulfate (CS). We previously purified squid GalNAc4S-6ST and cloned a cDNA encoding the partial sequence of squid GalNAc4S-6ST. In this paper, we cloned squid GalNAc4S-6ST cDNA containing a full open reading frame and characterized the recombinant squid GalNAc4S-6ST. The cDNA predicts a Type II transmembrane protein composed of 425 amino acid residues. The recombinant squid GalNAc4S-6ST transferred sulfate preferentially to the internal GalNAc(4SO(4)) residues of chondroitin sulfate A (CS-A); nevertheless, the nonreducing terminal GalNAc(4SO(4)) could be sulfated efficiently when the GalNAc(4SO(4)) residue was included in the unique nonreducing terminal structure, GalNAc(4SO(4))-GlcA(2SO(4))-GalNAc(6SO(4)), which was previously found in CS-A. Shark cartilage chondroitin sulfate C (CS-C) and chondroitin sulfate D (CS-D), poor acceptors for human GalNAc4S-6ST, served as the good acceptors for the recombinant squid GalNAc4S-6ST. Analysis of the sulfated products formed from CS-C and CS-D revealed that GalNAc(4SO(4)) residues included in a tetrasaccharide sequence, GlcA-GalNAc(4SO(4))-GlcA(2SO(4))-GalNAc(6SO(4)), were sulfated efficiently by squid GalNAc4S-6ST, and the E-D hybrid tetrasaccharide sequence, GlcA-GalNAc(4,6-SO(4))-GlcA(2SO(4))-GalNAc(6SO(4)) was generated in the resulting sulfated glycosaminoglycans. These observations indicate that the recombinant squid GalNAc4S-6ST is a useful enzyme for preparing a unique chondroitin sulfate containing the E-D hybrid tetrasaccharide structure. 相似文献
302.
Sato Takashi Onoma Noriyasu Fujikake Hiroyuki Ohtake Norikuni Sueyoshi Kuni Ohyama Takuji 《Plant and Soil》2001,237(1):129-135
Soybean nodules contain four major leghemoglobin (Lb) components, Lba, Lbc1, Lbc2 and Lbc3. A sensitive and selective method for quantitative analysis of the four Lb components was devised with capillary isoelectric focusing (CIEF). The changes in the concentrations of four Lb components in nodules during the initial stages of development were compared between hypernodulating soybean mutant NOD1–3 and its parent cv. Williams. The hydroponically cultivated soybean plants were periodically sampled. All the visible nodules were collected from the roots, and then the four Lb components in the largest nodules were analyzed with the CIEF method. In NOD1–3 Lbs were initially detected at 19 days after sowing (DAS), a few days earlier than in Williams at 22 DAS. The Lbcs (Lbc1, Lbc2 and Lbc3) were the main component at the earliest nodule growth stage, and the relative proportion of Lba increased with nodule growth in both NOD1–3 and Williams. This result is in agreement with previous observation, and the CIEF method is considered to be useful for Lb components analysis to define their function and gene expression. 相似文献
303.
Zhang Chunzhi Jin Fengxie Hisao Ohtake ** Kiyoshi TodaInstitute of Applied Microbiology of the University of Tokyo Department of Food Science Biotechnology Dalian College of Light Industry Baoding-Jie No. Zhongshan-Qu Dalian P. 《中国微生态学杂志》1999,(6)
Celluloseisthemostabundantnaturalbiopolymer.Howtoutilizeorhydrolyseitisaveryimportantprob-leminthefieldofbiotechnology.Sixstrains(JT)ofthermophilicanaerobicandcellulyticbacteriawereiso-latedfromcamelfeces,compost,soilandhotspringwa-terinJapan.Thesest… 相似文献
304.
Isolation and Characterization of Two Cryptic Plasmids in the Ammonia-Oxidizing Bacterium Nitrosomonas sp. Strain ENI-11
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Akira Yamagata Junichi Kato Ryuichi Hirota Akio Kuroda Tsukasa Ikeda Noboru Takiguchi Hisao Ohtake 《Journal of bacteriology》1999,181(11):3375-3381
Two plasmids were discovered in the ammonia-oxidizing bacterium Nitrosomonas sp. strain ENI-11, which was isolated from activated sludge. The plasmids, designated pAYS and pAYL, were relatively small, being approximately 1.9 kb long. They were cryptic plasmids, having no detectable plasmid-linked antibiotic resistance or heavy metal resistance markers. The complete nucleotide sequences of pAYS and pAYL were determined, and their physical maps were constructed. There existed two major open reading frames, ORF1 in pAYS and ORF2 in pAYL, each of which was more than 500 bp long. The predicted product of ORF2 was 28% identical to part of the replication protein of a Bacillus plasmid, pBAA1. However, no significant similarity to any known protein sequences was detected with the predicted product of ORF1. pAYS and pAYL had a highly homologous region, designated HHR, of 262 bp. The overall identity was 98% between the two nucleotide sequences. Interestingly, HHR-homologous sequences were also detected in the genomes of ENI-11 and the plasmidless strain Nitrosomonas europaea IFO14298. Deletion analysis of pAYS and pAYL indicated that HHR, together with either ORF1 or ORF2, was essential for plasmid maintenance in ENI-11. To our knowledge, pAYS and pAYL are the first plasmids found in the ammonia-oxidizing autotrophic bacteria. 相似文献
305.
Involvement of an Extracellular Protease in Algicidal Activity of the Marine Bacterium Pseudoalteromonas sp. Strain A28 总被引:9,自引:0,他引:9
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Sun-og Lee Junichi Kato Noboru Takiguchi Akio Kuroda Tsukasa Ikeda Atsushi Mitsutani Hisao Ohtake 《Applied microbiology》2000,66(10):4334-4339
The marine bacterium Pseudoalteromonas sp. strain A28 was able to kill the diatom Skeletonema costatum strain NIES-324. The culture supernatant of strain A28 showed potent algicidal activity when it was applied to a paper disk placed on a lawn of S. costatum NIES-324. The condensed supernatant, which was prepared by subjecting the A28 culture supernatant to ultrafiltration with a 10,000-Mw-cutoff membrane, showed algicidal activity, suggesting that strain A28 produced extracellular substances capable of killing S. costatum cells. The condensed supernatant was then found to have protease and DNase activities. Two Pseudoalteromonas mutants lacking algicidal activity, designated NH1 and NH2, were selected after N-methyl-N′-nitrosoguanidine mutagenesis. The culture supernatants of NH1 and NH2 showed less than 15% of the protease activity detected with the parental strain, A28. The protease was purified to homogeneity from A28 culture supernatants by using ion-exchange chromatography followed by preparative gel electrophoresis. Paper-disk assays revealed that the purified protease had potent algicidal activity. The purified protease had a molecular mass for 50 kDa, and the N-terminal amino acid sequence was determined to be Ala-Thr-Pro-Asn-Asp-Pro. The optimum pH and temperature of the protease were found to be 8.8 and 30°C, respectively, by using succinyl-Ala-Ala-Pro-Phe-p-nitroanilide as a substrate. The protease activity was strongly inhibited by phenylmethylsulfonyl fluoride, diisopropyl fluorophosphate, antipain, chymostatin, and leupeptin. No significant inhibition was detected with EDTA, EGTA, phenanthroline or tetraethylenepentamine. These results suggest that Pseudoalteromonas sp. strain A28 produced an extracellular serine protease which was responsible for the algicidal activity of this marine bacterium. 相似文献
306.
Shinichi Yoshihiro Masaru Ohtake Hajime Matsubara Koichiro Zamma Goro Han'ya Yasuaki Tanimura Hiroyuki Kubota Ritsuko Kubo Tatsuhiro Arakane Toru Hirata Mari Furukawa Aki Sato Yukio Takahata 《Primates; journal of primatology》1999,40(2):409-415
A census of wild Yakushima macaques (Macaca fuscata yakui) was carried out in a 23-km2 area of the western coast of Yakushima Island, Japan. We analyzed the census data to investigate changes in monkey distribution
associated with the vertical distribution of vegetation. In the lowland coastal zone of 0–300 m above sea level (a.s.l.),
4.8 troops and 62.4–99.8 monkeys are estimated to have existed per km2. In the mountainside zones of 300–900 m a.s.l., the troop density decreased to 1.3–1.6 troops/km2. Since there was no difference in size between the coastal and mountainside troops, population density should decrease with
altitude to about 30–36 monkeys per km2. On the other hand, 2.4 troops and about 36 monkeys were estimated to have inhabited per km2 in the mountain summit zone of 900–1,323 m a.s.l.
Nature Conservation College 相似文献
307.
We determined as to indole-3-acetic acid (IAA), endogenous levels byliquid chromatography-mass spectrometry using 13C6-IAA, diffusible levels byfluorometric detection using indole-propionic acid, and polar transportactivityby radioactive IAA in 3-month-old tomato plants (stems, leaves or roots). TheIAA concentration in the apoplast (AP) solution was higher than those in thesymplast (SP) solution in both the upper and lower parts of stems, showing thatIAA analysis of AP solution is important. Younger leaves exported much morediffusible IAA than older leaves. The IAA concentration in the main roots wasalmost at the same level as in the stems. The results suggested that thetransport capacity of IAA is probably the limiting factor for the amount of IAAtransported in stems and the amount of polar IAA transport might be only 19% ofthe endogenous IAA amount in stems. 相似文献
308.
David M Markusic Niek P van Til Johan K Hiralall PJ Oude Ronald Elferink Jurgen Seppen 《BMC biotechnology》2009,9(1):85
Background
Lentiviral vectors are well suited for gene therapy because they can mediate long-term expression in both dividing and nondividing cells. However, lentiviral vectors seem less suitable for liver gene therapy because systemically administered lentiviral vectors are preferentially sequestered by liver macrophages. This results in a reduction of available virus and might also increase the immune response to the vector and vector products. 相似文献309.
Effects of histamine and related compounds on the release of immunoreactive thyrotropin-releasing hormone (ir-TRH) from the rat stomach in vitro were studied. The rat stomach was incubated in medium 199 with 1.0 mg/ml of bacitracin and 100 micrograms/ml of ascorbic acid (pH 7.4) for 20 min. The amount of TRH release into the medium was measured by radioimmunoassay. The ir-TRH release from the rat stomach was enhanced significantly in a dose-related manner with the addition of histamine and inhibited with the addition of famotidine, but not with mepyramine. The stimulatory effect of histamine on ir-TRH release from the stomach was partially blocked with the addition of famotidine, but not with mepyramine. The elution profile of acid-methanol-extracted rat stomach on Sephadex G-10 was identical to that of synthetic TRH. These findings suggest that histamine stimulated ir-TRH release from the rat stomach in vitro, and that histamine's effects may be mediated via a H2-receptor. 相似文献
310.
Ishida T Ikeda T Takiguchi N Kuroda A Ohtake H Kato J 《Applied and environmental microbiology》2007,73(10):3183-3188
N-octanoyl cyclopentylamide (C8-CPA) was found to moderately inhibit quorum sensing in Pseudomonas aeruginosa PAO1. To obtain more powerful inhibitors, a series of structural analogs of C8-CPA were synthesized and examined for their ability to inhibit quorum sensing in P. aeruginosa PAO1. The lasB-lacZ and rhlA-lacZ reporter assays revealed that the chain length and the ring structure were critical for C8-CPA analogs to inhibit quorum sensing. N-decanoyl cyclopentylamide (C10-CPA) was found to be the strongest inhibitor, and its concentrations required for half-maximal inhibition for lasB-lacZ and rhlA-lacZ expression were 80 and 90 microM, respectively. C10-CPA also inhibited production of virulence factors, including elastase, pyocyanin, and rhamnolipid, and biofilm formation without affecting growth of P. aeruginosa PAO1. C10-CPA inhibited induction of both lasI-lacZ by N-(3-oxododecanoyl)-L-homoserine lactone (PAI1) and rhlA-lacZ by N-butanoyl-L-homoserine lactone (PAI2) in the lasI rhlI mutant of P. aeruginosa PAO1, indicating that C10-CPA interferes with the las and rhl quorum-sensing systems via inhibiting interaction between their response regulators (LasR and RhlR) and autoinducers. 相似文献