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S. Kleinle U. Wiesmann A. Superti-Furga S. Krähenbühl E. Boltshauser J. Reichen S. Liechti-Gallati 《Human genetics》1997,100(5-6):643-650
We used a strategy based on long PCR (polymerase chain reaction) for detection and characterization of mitochondrial DNA (mtDNA)
rearrangements in two patients with clinical signs suggesting Pearson syndrome and Kearns-Sayre syndrome (KSS), respectively,
and one patient with myopathic symptoms of unidentified origin. Mitochondrial DNA rearrangements were detected by amplification
of the complete mitochondrial genome (16.6 kb) using long PCR with primers located in essential regions of the mitochondrial
genome and quantified by three-primer PCR. Long PCR with deletion-specific primers was used for identification and quantitative
estimation of the different forms of rearranged molecules, such as deletions and duplications. We detected significant amounts
of a common 7.4-kb deletion flanked by a 12-bp direct repeat in all tissues tested from the patient with Pearson syndrome.
In skeletal muscle from the patient with clinical signs of KSS we found significant amounts of a novel 3.7-kb rearrangement
flanked by a 4-bp inverted repeat that was present in the form of deletions as well as duplications. In the patient suffering
from myopathic symptoms of unidentified origin we did not detect rearranged mtDNA in blood but found low levels of two rearranged
mtDNA populations in skeletal muscle, a previously described 7-kb deletion flanked by a 7-bp direct repeat and a novel 6.6-kb
deletion with no repeat. These two populations, however, were unlikely to be the cause of the myopathic symptoms as they were
present at low levels (10–40 ppm). Using a strategy based on screening with long PCR we were able to detect and characterize
high as well as low levels of mtDNA rearrangements in three patients.
Received: 10 March 1997 / Accepted: 20 May 1997 相似文献
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Continental‐scale macrofungal assemblage patterns correlate with climate,soil carbon and nitrogen deposition 下载免费PDF全文
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Christoph Syldatk Vera Lehmensiek Gaby Ulrichs Ulrich Bilitewski Karsten Krohn Hartmut Höke Fritz Wagner 《Biotechnology letters》1992,14(2):99-104
Summary Resting cells of a mutant ofArthrobacter sp. (DSM 3747) were used for the bioconversion of D,L-5-benzylhydantoin and related compounds to the corresponding L-amino acids. After optimization of the reaction conditions in shake flask experiments, bioconversions were performed in a preparative scale in a 2-l-bioreactor under nitrogen atmosphere. Specific productivities of 0.4 (p-NO2-L-phenylalanine) up to 3.9 mM amino acid x g cell dry mass–1 x h–1 (p-Cl-L-phenylalanine) were obtained. D,L-5-p-COOH-Benzylhydantoin, D,L-5-phenylhydantoin and D,L-5-p-OH-phenylhydantoin were not accepted as substrates. 相似文献
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Daniela Vullo Leo Syrjänen Marianne Kuuslahti Seppo Parkkila Claudiu T. Supuran 《Journal of enzyme inhibition and medicinal chemistry》2018,33(1):359-363
An anion inhibition study of the β-class carbonic anhydrase, AgaCA, from the malaria mosquito Anopheles gambiae is reported. A series of simple as well as complex inorganic anions, and small molecules known to interact with CAs were included in the study. Bromide, iodide, bisulphite, perchlorate, perrhenate, perruthenate, and peroxydisulphate were ineffective AgaCA inhibitors, with KIs?>?200?mM. Fluoride, chloride, cyanate, thiocyanate, cyanide, bicarbonate, carbonate, nitrite, nitrate, sulphate, stannate, selenate, tellurate, diphosphate, divanadate, tetraborate, selenocyanide, and trithiocarbonate showed KIs in the range of 1.80–9.46?mM, whereas N,N-diethyldithiocarbamate was a submillimolar AgaCA inhibitor (KI of 0.65?mM). The most effective AgaCA inhibitors were sulphamide, sulphamic acid, phenylboronic acid and phenylarsonic acid, with inhibition constants in the range of 21–84?µM. The control of insect vectors responsible of the transmission of many protozoan diseases is rather difficult nowadays, and finding agents which can interfere with these processes, as the enzyme inhibitors investigated here, may arrest the spread of these diseases worldwide. 相似文献
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The database systems PaleoTax and GONIAT provide detailed information on literature, taxonomy, morphology and occurrence of fossil invertebrate groups. PaleoTax is designed for Mesozoic corals, GONIAT for Paleozoic ammonoids, but both can be modified to cover other fossil groups. Both systems use dBASE format, but with different database structures. PaleoTax aims at the complete storage of all available objective data, GONIAT provides determinations based upon morphologic criteria, and includes information on geographic distribution and stratigraphic range of every taxon. A combination of both systems could lead to the establishment of a comprehensive paleontological information system useful for research and practical stratigraphic applications. 相似文献
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Immunohistochemical and physiological studies on various insect photoreceptors have demonstrated that the Na,K-ATPase (sodium pump) is restricted to the nonreceptive nonmicrovillar area of the plasma membrane. Here, we examined the distribution of the Na,K-ATPase in photoreceptor cells of the superposition-type compound eye in the moth Manduca sexta. Using immunofluorescent and immunogold cytochemistry, we show that the Na,K-ATPase is localized to both the nonmicrovillar and the microvillar parts of the plasma membrane. Manduca photoreceptors thus deviate from the common concept that the sodium pump and the molecular components of the photoreceptive machinery reside on different domains of the plasma membrane. 相似文献