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1.
Summary This is the first full report on the genetic linkage between Japanese Huntington's disease and the DNA markers D4S10 and D4S43/S127. With use of the HindIII, BglI, and EcoRI polymorphisms detected at D4S10, and the combination of all these polymorphisms to give composite haplotypes, nine Japanese Huntington's disease families were found to be informative. Three recombinants for D4S10 were detected in these families, giving a maximum lod score of 1.662 at a of 0.10. Similarly, when we used the MspI and PvuII polymorphisms detected by D4S43/S127, five families gave informative results. No recombinant was detected in these families, giving a maximum lod score of 3.348 at a of 0.00. These results clearly support the view that the Japanese Huntington's disease gene may be identical with the Western gene, in spite of the lower prevalence rate in Japan.  相似文献   
2.
Structure of the horseradish peroxidase isozyme C genes   总被引:13,自引:0,他引:13  
We have isolated, cloned and characterized three cDNAs and two genomic DNAs corresponding to the mRNAs and genes for the horseradish (Armoracia rusticana) peroxidase isoenzyme C (HPR C). The amino acid sequence of HRP C1, deduced from the nucleotide sequence of one of the cDNA clone, pSK1, contained the same primary sequence as that of the purified enzyme established by Welinder [FEBS Lett. 72, 19-23 (1976)] with additional sequences at the N and C terminal. All three inserts in the cDNA clones, pSK1, pSK2 and pSK3, coded the same size of peptide (308 amino acid residues) if these are processed in the same way, and the amino acid sequence were homologous to each other by 91-94%. Functional amino acids, including His40, His170, Tyr185 and Arg183 and S-S-bond-forming Cys, were conserved in the three isozymes, but a few N-glycosylation sites were not the same. Two HRP C isoenzyme genomic genes, prxC1 and prxC2, were tandem on the chromosomal DNA and each gene consisted of four exons and three introns. The positions in the exons interrupted by introns were the same in two genes. We observed a putative promoter sequence 5' upstream and a poly(A) signal 3' downstream in both genes. The gene product of prxC1 might be processed with a signal sequence of 30 amino acid residues at the N terminus and a peptide consisting of 15 amino acid residues at the C terminus.  相似文献   
3.
Three bacterial strains of Bifidobacterium and Clostridium sp. from patients with inflammatory bowel disease (I.B.D.) and Streptococcus pneumoniae from a patient with pneumonia were identified to produce extracellular proteases cleaving IgA into Fab and Fc fragments. Although the proteases from the Bifidobacterium and the Streptococcus pneumoniae showed the characteristics of typical IgA1 proteases, cleaving the IgA of only the IgA1 subclass, the protease from Clostridium sp. revealed a dual substrate specificity, in that it cleaved both IgA1 and IgA2 of the A2m(1) allotype. The latter protease, however, did not show any activity with respect to the IgA2 of the A2m(2) allotype. Fc fragments isolated from the IgA1 and the IgA2 A2m(1) by digestion with the Clostridium sp. protease were identified to have an identical amino terminal residue of valine. The site of cleavage in both the alpha 1 and the alpha 2 of A2m(1) by the protease was assumed to be an identical peptide bond at Pro(221)-Val(222), which is a common one present just before the hinge of both the alpha 1 and the alpha 2 of the A2m(1) but not of the alpha 2 of the A2m(2). The protease was sensitive to ethylene-diamino tetraacetic acid, a chelating agent, similar to other already reported IgA1 proteases.  相似文献   
4.
A bacterial strain isolated from feces of a patient with ulcerative colitis, which had been shown to produce a novel immunoglobulin A (IgA) protease (cleaving both the human IgA1 subclass and IgA2 subclass of A2m(1) allotype) extracellularly, was identified as Clostridium ramosum. By using a selective medium (propionate-rifampicin-gentamicin-colimycin-polymyxin medium) devised for C. ramosum, analysis of the population level of this organism was performed to determine its ecology in the human intestinal tract. C. ramosum was isolated in 20 of 25 fecal samples (80%) from patients with inflammatory bowel disease (I.B.D.) and in 112 of 135 samples (83%) from patients without I.B.D. (control group). C. ramosum was also isolated from 6 of 11 biopsy samples (55%) of the inflamed rectal mucosa from patients with ulcerative colitis and from five of 15 samples (33%) from the intact mucosa of the control group. The population levels of C. ramosum in most of the biopsy samples ranged from 2.3 to 5.0 log10 per gram. The IgA protease-positive C. ramosum was found in only four of 135 fecal samples (3%) and one of 15 biopsy samples (6.7%) from the control group. These results indicate that IgA protease-positive C. ramosum is not likely to play a role in the induction of I.B.D., unless the organism is first isolated from the patient with I.B.D.  相似文献   
5.
We report the biological characterization of an animal model of a genetic lipid storage disease analogous to human Wolman's disease. Affected rats accumulated cholesteryl esters (13.3-fold), free cholesterol (2.8-fold), and triglycerides (5.4-fold) in the liver, as well as cholesteryl esters (2.5-fold) and free cholesterol (1.33-fold) in the spleen. Triglycerides did not accumulate, and the levels actually decreased in the spleen. Analysis of the fatty acid composition of the cholesteryl esters and triglycerides showed high percentages of linoleic acid (18:2) and arachidonic acid (20:4) in both organs, especially in the liver. No accumulation of phospholipids, neutral glycosphingolipids, or gangliosides was found in the affected rats. Acid lipase activity for [14C]triolein, [14C]cholesteryl oleate, and 4-methyl-umbelliferyl oleate was deficient in both the liver and spleen of affected rats. Lipase activity at neutral pH was normal in both liver and spleen. Heterozygous rats showed intermediate utilization of these substrates in both organs at levels between those for affected rats and those for normal controls, although they did not accumulate any lipids. These data suggest that these rats represent an animal counterpart of Wolman's disease in humans.  相似文献   
6.
Japanese fireflies of the subfamily Luciolinae are biochemically analyzed using 13 allozymes, and the phylogenetic relationships obtained from this analysis are compared with their flash communication systems. As a result, the Japanese Luciolinae can be divided into three groups.Hotaria parvula andH. tsushimana together withLuciola yayeyamana andL. kuroiwae from the first group, and they use the same communication system.L. lateralis, Curtos okinawana, andC. costipennis make up the second group, and their communication systems are also the same.L. cruciata makes up the last one, and its communication system is different from the other fireflies of Luciolinae. Therefore, their taxonomical arrangement and communication systems are not congruent. However, the genetic similarity deduced by allozymic analysis of the members of the Japanese Luciolinae is highly consistent with their flash communication systems.  相似文献   
7.
Rhodium-catalyzed synthesis of 2(5H)-furanones from alkynes under water-gas shift reaction conditions was studied. By improving the reaction conditions for internal alkynes reported previously, the reaction could be extended to terminal alkynes. Terminal alkynes are selectively converted into 3- and 4-substituted 2(5H)-furanones (2 and 3). When acetylene itself is used, 2(5H)-furanone (2n) is obtained in a good yield. Examination of reaction solutions by IR spectroscopy and some other experimental findings suggest that the active species would be an alkyne-coordinated monomeric rhodium anion. A new reaction path is proposed.  相似文献   
8.
This article demonstrates the successful in situ real-time monitoring of the cell concentration of Perilla frutescens in a bioreactor by using a laser turbidimeter. It was found that turbidity measurements at 780 nm with the laser sensor were hardly affected by the red color of the anthocyanin produced by P. frutescens cells, nor by the aeration rate or agitation speed within the ranges investigated. There was an excellent linear relationship, with a correlation coefficient (r(2)) higher than 0.99, between the sensor's response and the cell concentration. The whole growth stage of the cells, i.e., lag, logarithmic, and stationary phases, in bioreactor cultivations, could be satisfactorily estimated on-line by means of the in situ turbidimeter. However, during the declining phase of the cells, an apparent deviation was observed between the on-line estimations and off-line measurements of cell concentrations by dry cell weight, while the wet cell weight could be estimated by the same turbidimeter system. We found that this deviation was caused by a decrease in the cell density due to an increase of the individual cell volume and a decrease of the cell dry weight during the declining phase. (c) 1993 John Wiley & Sons, Inc.  相似文献   
9.
The Nucleotide Sequence of Human Acylamino Acid-Releasing Enzyme   总被引:3,自引:0,他引:3  
The nucleotide sequence of a cDNA coding for the human acylaminoacid-releasing enzyme (AARE, also known as acylpeptide hydrolase)[EC 3.4.19.1] subunit has been determined. The amino acid sequenceof human AARE subunit deduced from its cDNA nucleotide sequenceshowed a high degree of identity (91.5%) with both the correspondingproteins from the pig and the rat. The AARE cDNA shows 99.2%identity with a 3.3 kb cDNA transcribed from a locus (DNF15S2)on the short arm of human chromosome 3, whose deletion is associatedwith small cell lung cancer, taking into consideration thatthe sequence of the 3.3-kb cDNA previously reported was causedby misreading.  相似文献   
10.
An E. coli tRNAfMet fragment [C-A-U-A-A-C-C-C-G-A-A-G-G-U-C-G-U-C-G-G (bases 35-f54)] containing the anticodon triplet has been synthesized by the phosphotriester method involving protected oligonucleotide blocks. Di- or tri-nucleotide blocks were prepared by condensation of 2'-O-(o-nitrobenzyl) nucleotide derivatives and used for the synthesis of pentanucleotide blocks. The 5'-hydroxy, heterocyclic amino and internucleotide linkage were protected with monomethoxytrityl, acyl and p-chlorophenyl groups, respectively. The 3'-phosphates of the pentanucleotides, except for the GUCGG block where 2'-O-benzoyl 3'-O-(o-nitrobenzyl) N-isobutyrylguanosine was used, were protected with p-chlorophenyl and anilido groups. The anilido groups were removed by treatment with isoamyl nitrite and the 3'-phosphodiesters of resulting pentamers were activated with mesitylenesulfonyl nitrotriazolide to give protected decanucleotides in yields of 61-89%. The two decanucleotides were condensed similarly to yield the protected eicosanucleotide in a yield of 59%. The product was deblocked and purified by ion-exchange chromatography on DEAE-Sephadex A-25 and characterized by enzymatic hydrolysis after labelling the 5'-end by phosphorylation using polynucleotide kinase and [gamma-32P]ATP.  相似文献   
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