生物物理化学
Online ISSN : 1349-9785
Print ISSN : 0031-9082
ISSN-L : 0031-9082
45 巻, 2 号
選択された号の論文の10件中1~10を表示しています
  • 廣川 健, 育田 夏樹, 吉山 竜也, 岡本 光, 芝山 貴幸, 真鍋 雄生
    2001 年 45 巻 2 号 p. 103-109
    発行日: 2001/06/15
    公開日: 2009/03/31
    ジャーナル フリー
    Although chromatography is widely utilized, it is behind the other analytical methods from the viewpoint of the standardization of the data. This is because usual chromatograms are strongly dependent on the used hardware. Capillary electrophoresis is not either the exception: The obtained electropherograms are also dependent on the hardware such as capillary length, capillary inner surface, applied voltage, and thermostatting capacity etc, even if the same background electrolyte and the same sample is used. We have developed a conversion method of the time-based electropherograms of capillary zone electrophoresis (CZE) into the mobility-based ones by removing contribution of electroosmotic flow considering temperature rise caused by Joule heating. The conversion method also contained correction for delay of migration time caused by relaxation of potential gradient at sample plug. In this paper, after discussing the factors affecting migration time of CZE, electropherograms of rare-earth ions obtained using different migration voltage were converted to demonstrate utility of our method proposed for standardization (data transfer). The conversion method was also successfully applied to electropherograms of several rations obtained by using field enhanced sample stacking.
  • 塚越 一彦
    2001 年 45 巻 2 号 p. 111-115
    発行日: 2001/06/15
    公開日: 2009/03/31
    ジャーナル フリー
    リポソームを使った免疫分析は, Kinsky らの報告以来盛んに研究されている. リポソームからシグナル発生物質が漏れ出る分析モードは, リポソーム膜の不安定化に基づいている. 漏れ出たシグナル発生物質の量は被検体の濃度に比例し, そのモニタリングは通常吸収または蛍光法で行われてきた. 我々は, 標識剤としての色素包括リポソームを化学発光検出する免疫分析法を提案した. これはキャピラリー電気泳動-化学発光検出法の免疫分析へのはじめての応用である. この方法で, ごく少ない試料を用いて, 簡便かつ迅速に高感度分析ができた. ここでは, 血清分析に関する一部新しいデータを付け加えて, 色素包括リポソームを用いた免疫分析法を開発の背景とともに簡単に紹介する.
  • 寺部 茂, Joselito P. Quirino, Michal J. Markuszewski, 井上 直子, 佐伯 知香, 大塚 浩二 ...
    2001 年 45 巻 2 号 p. 117-121
    発行日: 2001/06/15
    公開日: 2009/03/31
    ジャーナル フリー
    細胞内代謝中間産物の網羅的分析法開発にキャピラリー電気泳動の利用の可能性を評価するために行った予備実験結果の一部を報告する. PTHアミノ酸22種の一斉濃縮分離を酸性条件下MEKCにより行い, スウィーピング法により約5倍の試料濃縮ができた. 細胞内に代謝中間産物として含まれると考えられる芳香族カルボン酸6種についても濃縮分離を試みた. アルカリ性条件下スタッキングCZEにより25~30倍の濃縮が可能であった. 酸性条件下MEKCによる分離濃縮においてもほぼ同様の濃縮結果が得られた.
  • 佐塚 隆志
    2001 年 45 巻 2 号 p. 123-128
    発行日: 2001/06/15
    公開日: 2009/03/31
    ジャーナル フリー
    The whole genome sequence of unicellular cyanobacterium Synechocystis sp. strain PCC 6803 was completed in 1996 and nitrogen fixable filamentous cyanobacterium Anabaena sp. strain PCC 7120 is almost completed in our Kazusa DNA Research Institute. We initiated characterization of two organisms from a proteomic viewpoint by exploiting two-dimensional gel electrophoresis coupled with N-terminal protein sequencing. As a result, we succeeded in linking 347 protein spots on two-dimensional gels with the genes encoded on the genome of both species. These results provide us the “protein-gene linkage maps”of two cyanobacteria, which are highly beneficial for functional analysis of cyanobacteria at protein level. Compared two cyanobacterial proteomes with their whole genome sequences, we can extract many items of information concerning their surrounding nucleotide sequences of translation initiation site, rare initiation colons, post-translational processings (including translation initiator methionine processing, signal peptide processing and etc.) concerning to many functionally known and unknown cyanobacterial proteins. In consequence, comparative genomics together with comparative proteomics will serve us very valuable information comprehensive understanding of the molecular basis of cyanobacterial life.
  • 木村 弥生, 平野 久
    2001 年 45 巻 2 号 p. 129-137
    発行日: 2001/06/15
    公開日: 2009/03/31
    ジャーナル フリー
    The post-translational modification of proteasome has been investigated to determine the relation between function and the post-translational modification in the proteasome. The 26S proteasome is a large protein complex with proteolytic activity, consisting of 20S proteasome and 19S regulatory particle. In yeast, there are at least three N-acetyltransferases (NAT), NAT1, MAK3 and NAT3. Among 14 subunits of the 20S proteasome, the α1, α2, α3, α4, α7 and β3 subunits have been found to be N-acetylated with NAT1, the α5 and α6 subunits with MAK3, and the β4 subunit with NAT3. It was shown that chymotrypsin-like activity is slightly higher in the NAT1 deletion mutant than the normal strain, suggesting that N-acetylation be related to the proteolytic activity of 20S proteasome. The N-acetylation of 20S proteasome subunits in plants have been studied. In addition to the N-acetylated subunits in yeast, the β6 subunit has been deduced to be N-acetylated in plants. Similarly, N-terminal modification of the 19S regulatory particle has been investigated in yeast. Among 17 subunits identified in the 19S regulatory particle, 13 have been found to be N-terminally modified and at least 11 to be N-acetylated. On the other hand, phosphorylation is well-known post-translational modification in proteins. The phosphorylated subunits have been identified three in the yeast 20S proteasome and two in the mammal 19S regulatory particle. The relation between the proteolytic activity or assembly and phosphorylation of proteasome has been studied, suggesting that the post-translational modification of proteasome is important for its functions.
  • 戸田 年総
    2001 年 45 巻 2 号 p. 139-142
    発行日: 2001/06/15
    公開日: 2009/03/31
    ジャーナル フリー
    After completion of the Human Genome Project, the main target of the next research has shifted to elucidation of functions of unidentified novel genes. In this situation, expectation for the contribution of proteomic research to the bioinformatics has been getting heavier. The unification of genome database and proteome database may promote an advancement of post-genome researches. All spots of proteins isolated on a 2-D gel pattern can be easily assigned to their own sequence on a chromosome by tblastn search served by NCBI. After the mapping of all 2-D gel spot to genomic DNA, the function of unidentified genes will be thoroughly inquired by proteomic research. Many techniques in proteomics can offer much information about tissue/cell specific expression of the gene products, functional regulation by differentiation and carcinogenesis, intracellular localization, protein-to-protein interaction, and posttranslational modifications. A lot of information gathered by proteomic research may help us to assign a specific function to each protein corresponding to its unidentified gene.
  • 今井 浩三
    2001 年 45 巻 2 号 p. 143-148
    発行日: 2001/06/15
    公開日: 2009/03/31
    ジャーナル フリー
    Most cancers are genetically unstable and the instability exists at two distinct levels. Microsatellite instability (MIN) is observed at the nucleotide level, resulting in base substitutions or deletions or insertions of a few nucleotides. Chromosomal instability (CIN) is observed at the chromosome level and results in losses and gains of whole chromosomes or large portions. MIN is a characteristic of most hereditary nonpolyposis colorectal cancers (HNPCC). Approximately 15% of sporadic gastric and colorectal cancers also display MIN. Gastrointestinal cancers with MIN accumulate slippage-induced frameshift mutations in target genes such as type II TGFβ receptor and Bax. These cancers also have frequent aberrant DNA hypermethylation of tumor suppressor genes, including DNA mismatch repair gene hMLH1. A frequent loss of imprinting (LOI) of the insulin like growth factor II gene has been reported in colorectal cancers with MIN. On the other hand, mechanisms underlying CIN are beginning to be characterized. A small fraction of colorectal cancers have been shown to have mutations of the mitotic-checkpoint gene hBUB1 or hBUBR1. Cancers with MIN and those with CIN have been shown to exhibit fundamental differences in clinical, pathological, and molecular characteristics. From biological and clinical points of view, it is important to characterize the genetic instability of given tumors.
  • 舩渡 忠男, 藤巻 慎一, 佐藤 淳子, 小澤 鹿子, 賀来 満夫
    2001 年 45 巻 2 号 p. 149-152
    発行日: 2001/06/15
    公開日: 2009/03/31
    ジャーナル フリー
    Rapid advances in the field of molecular genetics have led to the need for a analytical assay. A number of methods have devised for this purpose, a material used the most widely is used the leukocytes DNA. In this study, we have reported the cases of three types. First, we found the cases who were heterozygotes for adenine phosphoribosyltransferase (APRT) gene mutations with APRT deficiency. Second, we evaluated the usefulness of a real-time reversed transcriptase polymerase chain reaction (RTPCR) system to detect minimal residual diseases. This method was applied a case who had t (8; 21) chimeric transcript in peripheral blood. Third, we evaluated a method to determine human cytomegalovirus (CMV) DNA levels in blood cells in a case transplaned liver. Thus, these methods were indicated possible applications for analysis using blood leukocytes.
  • 濱崎 直孝
    2001 年 45 巻 2 号 p. 153-157
    発行日: 2001/06/15
    公開日: 2009/03/31
    ジャーナル フリー
    By using a screening program to clarify the etiology of thrombophilia, we found protein S deficiency, either congenital or acquired, to be an important pathogenesis of thrombosis in the Japanese population. A gene analysis revealed that about one third of the patients with a low protein S activity are associated with varied mutations in the PROS 1 gene. Protein S (PS) is a nonenzymatic cofactor for activated protein C (APC) and plays an integral role as a regulator of APC that inhibits coagulation by enzymatically cleaving the activated forms of factor V and factor VIII. Approximately 60% of plasma PS circulates as a complex with C4b binding protein (C4BP), while the remainder circulates as free PS. Since only free PS has APC cofactor activity, a reduction in free PS is considered to be a cause of plasma PS deficiency. Factor V Leiden (R506Q) is resistant to the protein C/protein S anticoagulant pathway and is found in 20% to 60% of Caucasian patients with venous thrombosis. In Japan, no thrombotic patient having the factor V Leiden gene has been observed, instead, the decreased PS activity was found with a high incidence in thrombotic patients.
  • LDLサイズの測定法および small, dense LDL の臨床的意義
    芳野 原, 平野 勉, 鹿住 敏
    2001 年 45 巻 2 号 p. 159-164
    発行日: 2001/06/15
    公開日: 2009/03/31
    ジャーナル フリー
    Increased frequency of small, dense LDL is associated with the risk of coronary heart disease (CHD). Possible mechanisms include increased susceptibility of small, dense LDL to oxidation and its high affinity for LDL-receptor-independent cell surface binding sites. Although more than 30% of adult men in USA has been reported to have small, dense LDL, only 5.4% of young Japanese men had small, dense LDL. However, more than 70% of Japanese subjects with CHD had small, dense LDL, indicating a clinical importance of LDL size in the development of CHD in Japan. Furthermore, almost half of obese women (BMI>35kg/m2) had small, dense LDL. Our previous observation revealed that type 2 diabetics had smaller LDL even if they were apparently normolipidemic. There was also a close relationship between LDL size and plasma triglyceride even in the population with normotriglyceridemia, which may suggest that the plasma triglyceride is“the lower the better”from the stand point of LDL size. Finally, weight reduction of obese women by strict diet control, treatment of diabetics by acarbose or troglitazone and treatment of hyperlipidemia by a new statins, fluvastatin, were all successful in increasing LDL size associated with decreased plasma triglyceride.
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