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71.
Corrado Barghigiani Giuliano Colombetti Francesco Lenci Rosalba Banchetti Maria Pia Bizzaro 《Archives of microbiology》1979,120(3):239-245
We have investigated the effect of some metabolic drugs, 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU), 2,4-dinitrophenol (DNP), sodium azide (NaN3), on the photobehavior of single cells of Euglena gracilis, in order to clarify the relevance of different metabolic pathways in the process of photoperception and sensory transduction in this alga. The results obtained show that the photophobic response of Euglena is not affected by the action of these drugs. This suggests that neither the photosynthetic process nor oxidative phosphorylation play a significant role in the phenomenon of photosensory transduction in Euglena.List of Abbreviations DNP
2,4-dinitrophenol
- DCMU
3-(3,4-dichlorophenyl)-1,1-dimethylurea
- PSI
Photosystem I
- PSII
Photosystem II 相似文献
72.
The structure of the polysaccharide antigen produced by Eubacterium saburreum, strain L 32, has been investigated. The principal methods used were methylation analysis, graded hydrolysis with acid, and n.m.r. spectroscopy. The polysaccharide, which contains the unusual sugar 3,6-dideoxy-D-arabino-hexose (tyvelose, Tyv), is composed of trisaccharide repeating-units having the following structure: 相似文献
73.
The polysaccharide antigen produced by Eubacterium saburreum, strain L 49, is composed of D-glycero-D-galacto-heptose and a new sugar, tentatively identified as 6-deoxy-D-altro-heptose. It contains chains of alternating (1 leads to 3)- and (1 leads to 6)- linked beta-D-glycero-D-galacto-heptopyranosyl residues, the latter being substituted with 6-deoxy-alpha-heptofuranosyl groups at O-3. The polysaccharide further contains 0-acetyl groups, linked to O-7 of part of the heptosyl residues and to O-2 of part of the 6-deoxyheptosyl groups. 相似文献
74.
The structure of the capsular polysaccharide from Klebsiella type 59 has been investigated by methylation analysis, a modified Smith-degradation procedure, and uronic acid degradation followed by oxidation and elimination of the substituents of the oxidized residue. The oligomeric fragments produced by these degradative procedures were isolated and characterized. O-Acetyl groups were identified and their position determined. The polysaccharide consists of the following pentasaccharide repeating-unit (dotted lines indicate that only some of the residues carry the O-acetyl substituent). See article. 相似文献
75.
1. Brown adipose tissue of the hamster possesses high specific activities of soluble, cytoplasmic NAD-linked, as well as mitochondrial flavin-coupled, glycerol-3-phosphate dehydrogenases. The ratio of the two enzyme activities is high (close to 1), when compared with other tissues of the hamster. 2. In the presence of rotenone, NADH is oxidised very poorly by homogenates of brown adipose tissue. A high rate of oxidation is obtained upon further addition of dihydroxyacetone phosphate, which itself is negligible oxidised. When followed fluorimetrically glycerol 3-phosphate can also be observed to induce NADH oxidation, but only after a significant lag time. Similar results are obtained with isolated mitochondria plus high-speed supernatant. With high-speed supernatant alone, only dihydroxyacetone phosphate has any effect, whereas with isolated mitochondria neither dihydroxyacetone phosphate nor glycerol 3-phosphate induce any NADH disappearance. 3. Respiration induced by NADH plus dihydroxyacetone phosphate in homogenates equals 56% of the respiration induced by glycerol 3-phosphate alone. 4. Respiration induced by NADH plus dihydroxyacetone phosphate, as well as that induced by glycerol 3-phosphate, is inhibited by the same concentrations of inhibitors as are required for inhibition of the mitochondrial dehydrogenase i.e. EDTA, long-chain unsaturated fatty acids, long-chain fatty acyl CoA esters. 5. In isolated brown adipocytes in the presence of rotenone, norepinephrine significantly inhibits respiration induced by glycerol 3-phosphate. 6. The results obtained are discussed with respect to the role of glycerol 3-phosphate as an electron sink for cytosolic reducing equivalents to maintain a low level of extramitochondrial NADH. A means of maintaining a level of glycerol 3-phosphate adequate for triglyceride synthesis is also considered. 相似文献
76.
Bror Edlund Jill Andersson Vincent Titanji Ulla Dahlqvist Pia Ekman Örjan Zetterqvist Lorentz Engström 《Biochemical and biophysical research communications》1975,67(4):1516-1521
One dominating peptic phosphopeptide, Asx-Thr-Lys-Gly-Pro-Glx-Ile-Glx-Thr-Gly-Val-Leu-Arg-Arg-Ala-(32P)SerP-Val-Ala-Glx-Leu, was obtained from rat liver pyruvate kinase (type L) phosphorylated by cyclic 3′,5′-AMP-stimulated protein kinase from the same tissue. The sequence around the phosphorylated serine residue is similar to that of a corresponding but smaller peptic phosphopeptide previously isolated from pig liver (type L) pyruvate kinase, Leu-Arg-Arg-Ala-(32P)SerP-Leu. 相似文献
77.
Studies of a receptor for felix O-1 phage in Salmonella minnesota 总被引:16,自引:0,他引:16
A A Lindberg 《Journal of general microbiology》1967,48(2):225-233
78.
79.
Olga Fedotovskaya Ingrid Albertsson Gustav Nordlund Sangjin Hong Robert B. Gennis Peter Brzezinski Pia Ädelroth 《BBA》2021,1862(8):148433
Respiration is carried out by a series of membrane-bound complexes in the inner mitochondrial membrane or in the cytoplasmic membrane of bacteria. Increasing evidence shows that these complexes organize into larger supercomplexes. In this work, we identified a supercomplex composed of cytochrome (cyt.) bc1 and aa3-type cyt. c oxidase in Rhodobacter sphaeroides. We purified the supercomplex using a His-tag on either of these complexes. The results from activity assays, native and denaturing PAGE, size exclusion chromatography, electron microscopy, optical absorption spectroscopy and kinetic studies on the purified samples support the formation and coupled quinol oxidation:O2 reduction activity of the cyt. bc1-aa3 supercomplex. The potential role of the membrane-anchored cyt. cy as a component in supercomplexes was also investigated. 相似文献