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11.
Hiromi Toyama Eriko Hayashi Kozo Nagaoka Yujiro Yamada 《Bioscience, biotechnology, and biochemistry》2013,77(8):1859-1864
To establish a procedure for high frequency transfection in streptomycetes, the conditions and factors affecting the polyethyleneglycol (PEG) mediated transfection of S. chartreusis SF1623 by actinophage Φr5 DNA were studied. Protoplasts of S. chartreusis SF1623 prepared by treatment with lysozyme and achromopeptidase were very stable. Protoplasts from 20 to 22hr culture cells were more competent for transfection. The optimal pH of the medium for transfection was pH 7.6. The presence of NaCl, thymidine, ATP, ADP or adenosine in the transfection medium enhanced the frequency of transfection. The optimal conditions determined for protoplast transfection were 12.5% PEG 4,000, 300 mm NaCl, 1 mm thymidine, final concentration, Φr5 DNA and protoplasts in P3 medium (pH 7.6). The frequency of transfection under the optimal conditions was 5 × 105 per μg Φr5 DNA and was about 3 × 10?3 per regenerated protoplasts.Progenitively mature phages appeared 4hr after incubation in the regeneration solution and their number continued to increase for about 11 hr. The burst size was estimated to be about 400. 相似文献
12.
Adam Ahanchédé José E. F. Alfaya L. W. Andersen Didier Azam Ma. Anita M. Bautista Anne‐Laure Besnard Gregorio Bigatti Anthony Bouétard Marie‐Agnès Coutellec Eben‐Ezer B. K. Ewédjè Reiko Fuseya Ricardo GarcÍa‐Jiménez M. Haratian Olivier J. Hardy L.‐E. Holm Casey W. Hoy Eriko Koshimizu V. Loeschcke Violeta López‐Márquez Carlos A. Machado Annie Machordom C. Marchi Andrew P. Michel Claire Micheneau Omprakash Mittapalli Takahiro Nagai Nobuaki Okamoto Ying Pan F. Panitz N. Safaie Takashi Sakamoto B. Sharifnabi En‐Wei Tian Hui Yu 《Molecular ecology resources》2013,13(1):158-159
This article documents the addition of 83 microsatellite marker loci and 96 pairs of single‐nucleotide polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Bembidion lampros, Inimicus japonicus, Lymnaea stagnalis, Panopea abbreviata, Pentadesma butyracea, Sycoscapter hirticola and Thanatephorus cucumeris (anamorph: Rhizoctonia solani). These loci were cross‐tested on the following species: Pentadesma grandifolia and Pentadesma reyndersii. This article also documents the addition of 96 sequencing primer pairs and 88 allele‐specific primers or probes for Plutella xylostella. 相似文献
13.
14.
Hiyoshi W Sasaki T Takayama-Watanabe E Takai H Watanabe A Onitake K 《Journal of experimental zoology. Part A, Ecological genetics and physiology》2007,307(6):301-311
The acrosome reaction of newt sperm is induced at the surface of egg jelly and the acrosome-reacted sperm acquire the ability to bind to the vitelline envelope. However, because the substance that induces the acrosome reaction has not been identified, the mechanism by which the acrosome-reacted sperm bind to the vitelline envelope remains unclear. We found here that a Dolichos biforus agglutinin (DBA) specifically mimicked the acrosome reaction immediately upon its addition in the presence of milimolar level Ca(2+). Fluorescein isothiocyanate-labeled DBA bound specifically to the acrosomal cap of the intact sperm in the presence of a Ca(2+)-chelating agent, EDTA, suggesting that binding of DBA to the native receptor for the egg jelly substance on the acrosomal region took the place of the egg jelly substance-induced acrosome reaction. In contrast, the sperm that had been acrosome reacted by DBA treatment did not bind to the vitelline envelope of the egg whose jelly layers were removed. Subsequent addition of jelly extract caused the sperm binding to vitelline envelope, indicating that the egg jelly of the newt contains substances that are involved in not only inducing the acrosome reaction but also binding to the vitelline envelope. This is the first demonstration of the involvement of egg jelly substance in the binding of acrosome-reacted sperm to the vitelline envelope. 相似文献
15.
Taurine inhibits apoptosis by preventing formation of the Apaf-1/caspase-9 apoptosome 总被引:5,自引:0,他引:5
Takatani T Takahashi K Uozumi Y Shikata E Yamamoto Y Ito T Matsuda T Schaffer SW Fujio Y Azuma J 《American journal of physiology. Cell physiology》2004,287(4):C949-C953
Cardiomyocyte apoptosis contributes to cell death during myocardial infarction. One of the factors that regulate the degree of apoptosis during ischemia is the amino acid taurine. To study the mechanism underlying the beneficial effect of taurine, we examined the interaction between taurine and mitochondria-mediated apoptosis using a simulated ischemia model with cultured rat neonatal cardiomyocytes sealed in closed flasks. Exposure to medium containing 20 mM taurine reduced the degree of apoptosis following periods of ischemia varying from 24 to 72 h. In the untreated group, simulated ischemia for 24 h led to mitochondrial depolarization accompanied by cytochrome c release. The apoptotic cascade was also activated, as evidenced by the activation of caspase-9 and -3. Taurine treatment had no effect on mitochondrial membrane potential and cytochrome c release; however, it inhibited ischemia-induced cleavage of caspase-9 and -3. Taurine loading also suppressed the formation of the Apaf-1/caspase-9 apoptosome and the interaction of caspase-9 with Apaf-1. These findings demonstrate that taurine effectively prevents myocardial ischemia-induced apoptosis by inhibiting the assembly of the Apaf-1/caspase-9 apoptosome. ischemia; cultured cardiomyocytes 相似文献
16.
Sese J Kurokawa Y Monden M Kato K Morishita S 《Bioinformatics (Oxford, England)》2004,20(17):3137-3145
MOTIVATION: Gene expression profiles should be useful in distinguishing variations in disease, since they reflect accurately the status of cells. The primary clustering of gene expression reveals the genotypes that are responsible for the proximity of members within each cluster, while further clustering elucidates the pathological features of the individual members of each cluster. However, since the first clustering process and the second classification step, in which the features are associated with clusters, are performed independently, the initial set of clusters may omit genes that are associated with pathologically meaningful features. Therefore, it is important to devise a way of identifying gene expression clusters that are associated with pathological features. RESULTS: We present the novel technique of 'itemset constrained clustering' (IC-Clustering), which computes the optimal cluster that maximizes the interclass variance of gene expression between groups, which are divided according to the restriction that only divisions that can be expressed using common features are allowed. This constraint automatically labels each cluster with a set of pathological features which characterize that cluster. When applied to liver cancer datasets, IC-Clustering revealed informative gene expression clusters, which could be annotated with various pathological features, such as 'tumor' and 'man', or 'except tumor' and 'normal liver function'. In contrast, the k-means method overlooked these clusters. 相似文献
17.
Takamura M Sakurai M Yamada E Fujita S Yachi M Takagi T Isobe A Hagisawa Y Fujiwara T Yanagisawa H 《Bioorganic & medicinal chemistry》2004,12(9):2419-2439
We previously reported the identification of novel oximes having 5-benzyl-2,4-thiazolidinedione with antihyperglycemic activity. We now report the synthesis and biological activity of a novel series of oximes and amides having alpha-substituted-beta-phenylpropionic acids. In this series, we obtained potent PPAR alpha/gamma dual agonist (S)-9d, with which activation of PPAR alpha and PPAR gamma was considerably more potent than that of the reference compounds GW9578 22 and rosiglitazone 3, respectively. This means (S)-9d is of the strongest class of PPAR alpha/gamma dual agonists. In the course of this study, we also obtained 8h, which indicated potent plasma glucose lowering effect in spite of weak PPAR alpha/gamma agonistic activity. 相似文献
18.
Tomitsuka E Hirawake H Goto Y Taniwaki M Harada S Kita K 《Journal of biochemistry》2003,134(2):191-195
Succinate-ubiquinone reductase (complex II) is an important enzyme complex in both the tricarboxylic acid cycle and aerobic respiration. A recent study showed that defects in human complex II are associated with cancers as well as mitochondrial diseases. Mutations in the four subunits of human complex II are associated with a wide spectrum of clinical presentations. Such tissue-specific clinical symptoms suggest the presence of multiple isoforms of the subunits, but subunit isoforms have not been previously reported. In the present study, we identified two distinct cDNAs for the human flavoprotein subunit (Fp) from a single individual, and demonstrated expression of these two isoforms in skeletal muscle, liver, brain, heart and kidney. Interestingly, one of the Fp isoforms was encoded as an intronless gene. 相似文献
19.
Zheng R Matsui E Shen Y Musti KV Feng Y Darnis S Kawarabayasi Y Kikuchi H Harata K Matsui I 《Extremophiles : life under extreme conditions》2001,5(2):111-117
The DNA polymerase gene of the hyperthermophile Pyrococcus horikoshii was successfully overexpressed after removing an intein. The importance of an amino acid sequence around a highly conserved Asp was studied by site-directed mutagenesis. The results indicated that Lys253, Arg255, and Asp259 form a novel functional motif, K253xRxxxD259 (outside known motifs Exo I, II, and III), that is important not only for exonuclease activity but also for polymerizing activity, confirming functional interdependence between the polymerase and exonuclease domains. The short loop region, K253G254R255, probably contributes to binding to DNA substrates. Moreover, the negative charge and the side-chain length of D259 might play a supporting role in coordinating the conserved Mg2+ to the correct position at the active center in the exonuclease domain. 相似文献
20.
Detergent resistant membranes (DRMs) have been implicated in numerous cellular processes including signal transduction, membrane trafficking, and molecular sorting. Flotillins-1 and -2 have recently been shown to be large components of erythrocyte DRMs. In this study, we show that a Plasmodium falciparum infection disrupts the association of flotillins with erythrocyte DRMs. Flotillins are probably released from erythrocyte DRMs through the reduction of cholesterol and sphingomyelin levels during the course of a P. falciparum-infection. Although it is well known that a P. falciparum infection can modify the host erythrocyte membrane, this is the first report that P. falciparum can alter the DRM components of erythrocyte membranes. 相似文献