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41.
A collection of programs for nucleic acid and protein analysis, written in FORTRAN 77 for IBM-PC compatible microcomputers. 总被引:7,自引:0,他引:7 下载免费PDF全文
We have developed a collection of programs for manipulation and analysis of nucleotide and protein sequences. The package was written in Fortran 77 on a Sirius1/Victor microcomputer which can be easily implemented on a large variety of other computers. Some of the programs have already been adapted for use on a Vax 11. Our aim was to develop programs consisting of small, comprehensible and well documented units that have very fast execution times and are comfortably interactive. The package is therefore suitable for individual modifications, even with little understanding of computer languages. 相似文献
42.
Prolyl hydroxylase, which is responsible for the hydroxylation of peptidyl proline residues, has been isolated and purified from the green alga Chlamydomonas reinhardii. The enzyme, which appears to be loosely associated with microsomal membranes, was released into solution by sonication in the presence of detergent. Purification was achieved by ion-exchange chromatography followed by affinity chromatography using the immobilized substrate poly-L-proline. Apart from its differing substrate specificity the enzyme appears to possess similar molecular characteristics to prolyl hydroxylase isolated from animal tissues: the active enzyme is a tetramer of about 240–250 kDa and nonidentical monomers of 65 and 60 kDa. The monomers are capsule shaped having a dimension of 12×7 nm.Abbreviations Da
dalton
- DEAE
diethylaminoethyl
- DTT
dithiothreitol
- Hepes
4-(2-hydroxymethyl)-1-piperazine ethanesulfonic acid
- -KGA
-ketoglutarate
- PAGE
polyacrylamide gel electrophoresis
- SDS
sodium dodecyl sulfate 相似文献
43.
Continuous production of L-tryptophan from indole and L-serine by immobilized Escherichia coli cells 总被引:1,自引:0,他引:1
Escherichia coli B 10, which has high activity of tryptophan synthetase, was grown in a 50-L batch culture in order to determine in which growth phase the cells have the highest specific tryptophan productivity. Accordingly, whole cells of the stationary phase were used for immobilization in polyacrylamide beads. After immobilization, these immobilized cells had 56% activity of tryptophan synthetase compared with that of free cells. First, the properties of immobilized cells were investigated. Next, discontinuous productions of L-tryptophan were carried out by using immobilized cells. In discontinuous production of L-tryptophan by the batch, the activity remaining of immobilized cells was 76-79% after 30 times batchwise use. In continuous production of L-tryptophan with a continuous stirred tank reactor (CSTR), the activity remaining of the immobilized cells was 80% after continuous use for 50 days. The maximum productivity of L-tryptophan in this CSTR system was 0.12 g tryptophan L(-1) h(-1). 相似文献
44.
Five species of cultured Trebouxia—T. anticipata, T. decolorans, T. erici, T. gelatinosa, and T. impressa—were examined with the electron microscope. A comparative examination of their pyrenoids revealed pyrenoglobuli associated with single pyrenoid thylakoids. The pyrenoids of T. decolorans, T. erici, and T. gelatinosa possess single thylakoids that cross or deeply penetrate the pyrenoid matrix and are often disposed in parallel arrays. T. anticipata possesses both single and double pyrenoid thylakoids within the matrix. T. impressa possesses vesiculate invaginations of thylakoid membranes into the pyrenoid matrix. The phycobiont. T. erici was examined in detail at the light and electron microscopic levels for pyrenoid alterations associated, with varied environmental regimes and with cell division. A greater amount of starch is present in cells grown in organic culture at 215 lux light intensity than in cells of similar size grown at 1075 or 3600 lux. Pyrenoglobuli are present throughout the life cycle and occur both in aplanospores and in zoospores. 相似文献
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Continuous transpiration and β-guage measurements were made on cotton plants, the stomatal apertures of which had been induced to oscillate, thus allowing a water balance to be made, and leaf potential to be measured as functions of time. 相似文献
47.
Summary The plant growth retardants (2-chloroethyl)-trimethylammonium chloride (CCC) and 2-isopropyl-4-(trimethylammoniumchloride)-5-methylphenyl-piperidine-1-carboxylate (AMO-1618) inhibit gibberellic-acid biosynthesis inFusarium moniliforme at the cyclisation of geranylgeraniol to (-)-kaurene, causing an accumulation of geranylgeraniol. The two inhibitors have no effect on the biosynthesis of ergosterol inF. moniliforme or sitosterol in barley seedlings. 相似文献
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Johannes Lang 《Cell and tissue research》1964,63(2):226-246
Zusammenfassung Die Gefäße sprossen während zweier Wachstumsphasen in den Nerv ein: bei 11 cm langen Feten liegen 125 Gefäße innerhalb des N. tibialis (R. poplitea), auch bei 23 cm langen Feten finden sich etwa gleichviel Haargefäße im Endoneuralraum. Bei 39 cm langen Feten hat sich die Kapillarzahl etwa verdreifacht. Die Kapillarzahl pro Quadratmillimeter Endoneuralraum ist tabellarisch zusammengefaßt, die kritische Schichtdicke für einzelne Altersstufen errechnet worden.Bereits beim 11 cm langen Feten sind innerhalb des Nerven zarte Septen zu erkennen, aus denen sich bei 16 cm langen das Stratum lamellare perineurii entwickelt hat. Die Zahl der Lamellen vermehrt sich während des intrauterinen Lebens bis auf fünf. Das Stratum fibrosum perineurii et epineurii entwickelt sich erst beim über 35 cm langen Feten. Als erste Bindegewebsstruktur legen sich Teile des interfaszikulären Bindegewebes in Form von dreieckigen Zwickeln um die größeren Nervengefäße. Gleichzeitig runden sich die vorher eckig begrenzten Nervenfaserbündel ab. Während des intrauterinen Wachstums verdicken sich die Faszikel stetig. Allerdings schwanken Zahl und Durchmesser der Faszikel eines Nervs erheblich (Tabelle 2).Das Nervenbindegewebe nimmt während des Wachstums kontinuierlich zu (Tabelle 3). An der Umbiegungsstelle des N. tibialis sind die Faszikel vermehrt und verkleinert. Außerdem lassen sich mehr Bindegewebsanteile am Nervenquerschnitt ermitteln (Tabelle 4).In Injektionspräparaten von Nerven alter Menschen sind endoneurale Degenerationsherde (Renautsche Körperchen) aufgefunden worden. Da innerhalb der betroffenen Faszikel die Kapillarzahl um die Anzahl der Degenerationsherde vermindert ist, wird angenommen, daß diese Gebilde untergegangen und nekrobiotisch veränderten Kapillaren entsprechen.Diese Deutung wird gestützt durch Befunde an Kapillaren in der Umgebung der Degenerationsbezirke, deren Grundhäutchen verdickt und hyalinisiert sind.Im gelähmten Nerv nimmt das Bindegewebe relativ zur schrumpfenden Nervensubstanz zu.Herrn Professor Dr. Fritz Wassermann zum 80. Geburtstag in Verehrung gewidmet. 相似文献