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91.
Five novel representatives of the yeast genus Candida isolated from advanced stages of wood degradation from fallen trunks of Eucryphia cordifolia Cav., Laurelia sempervirens Weim., Laurelia philippiana Weim., Nothofagus dombeyii (Mirb.) Blume, and Nothofagus obliqua (Mirb.) Blume, in the evergreen rainy Valdivian forest of southern Chile, are described and illustrated. They clearly differ from all accepted Candida species to warrant their establishment as five new species of yeasts: Candida coipomensis sp. nov., Candida ralunensis sp. nov., Candida laureliae sp. nov., Candida osornensis sp. nov., and Candida llanquihuensis sp. nov. 相似文献
92.
Four unusual Apiotrichum, isolated from decayed wood of Eucryphia cordifolia Cav., Nothofagus obliqua (Mirb.) Blume, and Laurelia sempervirens Wein., one of which was also isolated from the intestinal tract of Scaptomyza multispinosa Malloch (Diptera), are described and illustrated. These species differ from all the accepted Apiotrichum species (1–3) to warrant their establishment as four new species: Apiotrichum eucryphiae, Apiotrichum osvaldii, Apiotrichum futronensis and Apiotrichum nothofagi. 相似文献
93.
Two unusual species of Candida and one variety of one of them, isolated from decayed wood (palo podrido) (12) in the ultimate stages of degradation, are described and illustrated. They differ sufficiently from all accepted Candida species to warrant their establishment as two new species and one variety: Candida railenensis, Candida bertae, and Candida bertae var. chiloensis.The DNA base composition of these yeasts was not calculated, since our laboratory is not properly equipped for that purpose. 相似文献
94.
Oren Zinder Philip G. Hoffman William M. Bonner Dr Harvey B. Pollard 《Cell and tissue research》1978,188(2):153-170
Summary A highly enriched fraction of plasma membranes from the bovine adrenal medulla has been isolated by differential and sucrose gradient centrifugation. The membranes were found to occur as 0.1–0.5 diameter vesicles and to equilibrate at a density of 1.13–1.14 g/ml. This fraction was characterized by 4-fold elevated levels of adenylate cyclase and 20-fold elevated levels of 5-nucleotidase. Secretory vesicle membranes, isolated by repeated hypotonie and hypertonic shocks of whole vesicles, were found to equilibrate between d = 1.08 and d = 1.12 on a sucrose density step gradient. These membranes were highly enriched in cytochrome b562 and dopamine--hydroxylase. Proteins in the two membranes were compared by SDS gel electrophoresis. All protein size classes found in the vesicle membrane fraction were also represented in the plasma membrane fraction, though in different proportions on the basis of staining intensity. The plasma membrane fraction contained prominent bands co-migrating with the - and -bands of tubulin, as well as a component co-migrating with actin. These bands were absent from the vesicle membranes. Fingerprint analysis of stained bands from the membrane fraction demonstrated that the components were indeed tubulin and actin. The plasma membranes contained twice as much sialic acid residues as did the chromaffin granule membranes, but had only half the cholesterol content on a weight basis. The cholesterolphospholipid ratio in the plasma membranes was 0.63, while in the secretory vesicle membranes it was 1.04. These results show that plasma membranes and secretory vesicle membranes are functionally and structurally different.Supported, in part, by a stipend to O.Z. from The Grant Foundation, New York 相似文献
95.
Occurrence of facultative anoxygenic photosynthesis among filamentous and unicellular cyanobacteria. 总被引:7,自引:0,他引:7 下载免费PDF全文
Eleven of 21 cyanobacteria strains examined are capable of facultative anoxygenic photosynthesis, as shown by their ability to photoassimilate CO2 in the presence of Na2S, 3-(3,4-dichlorophenyl)-1,1-dimethylurea and 703-nm light. These include different cyanobacterial types (filamentous and unicellular) of different growth histories (aerobic, anaerobic, and marine and freshwater). Oscillatoria limnetica, Aphanothece halophytica (7418), and Lyngbya (7104) have different optimal concentrations of Na2S permitting CO2 photoassimilation, above which the rate decreases: 3.5, 0.7, and 0.1 mM, respectively. In A. halophytica, for each CO2 molecule photoassimilated two sulfide molecules are oxidized to elemental sulfur, which is excreted from the cells.The ecological and evolutionary significance of anoxygenic photosynthesis in the cyanobacteria is discussed. 相似文献
96.
Two new compounds G and H isolated from the roots of Costus speciosus have been characterized as 8-hydroxytriacontan-25-one and Me tritriacontanoat 相似文献
97.
Characterization and Translation of Poly(A)+RNA from Wounded and Crown Gall Tissues of Potato Tubers
Poly(A)+ and poly(A)RNA from wounded potato tuber tissuesand crown gall tumors were separated from total RNA by oligodeoxythymidylicacid-cellulose affinity chromatography. The poly(A)+RNA wascharacterized by sucrose density gradient centrifugation, hybridizationwith 3(H)polyuridylic acid [Poly(U)] and in vitro translationin a rabbit reticulocyte lysate system. The tumor poly(A)+RNAwas a heterodisperse mixture from 3.5S to 35S. Upon poly(U)hybridization of the gradient fractions two major hybridizationpeaks at 7S and 21S and two peaks at 11S and 16S appeared. Inan in vitro translation system the poly(A)+RNA programmed thesynthesis of 23 different polypeptides of 9,000 to 79,800 daltonsmolecular weight as determined by SDS-polyacrylamide gel electrophoresis.The 21S poly(A)+RNA was about 5 times more active in in vitroprotein synthesis than the 7S poly(A)+RNA. The poly(A)+RNA from wounded tissues was also heterodisperse(from 4.5S to 31S) with a modal peak at 18S. This RNA codedfor at least 28 polypeptides, which were different from thoseof crown gall tumor tissues. On a per unit poly(A)+RNA basis the tumor RNA was slightly moreactive in translation than that from wounded tissues. The translationof tumor poly(A)+RNA was completely blocked by 0.5 mM 7-methylguanosine5'-phosphate, but not by 7-methylguanosine, suggesting the presenceof a 5'-cap structure. (Received May 15, 1982; Accepted June 30, 1982) 相似文献
98.
Estimation of Sediment Denitrification Rates at In Situ Nitrate Concentrations 总被引:10,自引:9,他引:1 下载免费PDF全文
The denitrification rates in a marine sediment, estimated by using 15N-nitrate, Vmax, Km, and sediment nitrate concentrations, were 12.5 and 2.0 nmol of N2-N cm−3 day−1 at 0 to 1 and 1 to 3 cm, respectively, at 12°C. The total rate was 165 nmol of N2-N m−2 day−1. 相似文献
99.
Aqueous solutions of silver nitrate (10–100 g/plant) and cobalt chloride (125–500 g/plant), injected into the main stem of plants of the pistillate cv. 240 ofRicinus communis when the vegetative shoot apex was beginning to become reproductive, induced the formation of staminate (male) flowers with viable pollen in the normally strictly pistillate (female) terminal inflorescence, their number increasing with the dose of Ag+ and Co2+. No formation of bisexual flowers was noted. Female flowers pollinated with pollen from the induced male ones produced fruits and viable seeds. 相似文献
100.
R Oren S Weiss H Garty S R Caplan Z Gromet-Elhanan 《Archives of biochemistry and biophysics》1980,205(2):503-509
The coupling factor ATPase complex extracted by Triton X-100 from the photosynthetic bacterium Rhodospirillum rubrum could be incorporated into phospholipid vesicles after removal of the Triton. Vesicles reconstituted with this F0 · F1-type ATPase together with bacteriorhodopsin were found to catalyze, in the light, net ATP synthesis which was inhibited by the energy transfer inhibitors oligomycin and N,N-dicyclohexylcarbodiimide as well as by uncouplers. In vesicles reconstituted with the crude ATPase up to 50% of the observed rate of phosphorylation was independent on light and bacteriorhodopsin and insensitive to the above-listed inhibitors. This dark activity was, however, completely blocked by the adenylate kinase inhibitor, p1,p5-di(adenosine-5′)pentaphosphate, which did not affect at all the net light-dependent phosphorylation nor the ATP-32Pi exchange reaction. Vesicles reconstituted with the purified ATPase catalyzed only the light- and bacteriorhodopsin-dependent diadenosine pentaphosphate-insensitive phosphorylation. The rate of this photophosphorylation was found to be proportional to the amount of ATPase and bacteriorhodopsin, and linear for at least 20 min of illumination. These results indicate that the purified ATPase contains the complete assembly of subunits required to transduce electrochemical gradient energy into chemical energy. 相似文献