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11.
Neuza Domingues André R. A. Marques Rita Diogo Almeida Calado Inês S. Ferreira Cristiano Ramos José Ramalho Maria I. L. Soares Telmo Pereira Luís Oliveira José R. Vicente Louise H. Wong Inês C. M. Simões Teresa M. V. D. Pinho e Melo Andrew Peden Cláudia Guimas Almeida Clare E. Futter Rosa Puertollano Winchil L. C. Vaz Otília V. Vieira 《Traffic (Copenhagen, Denmark)》2023,24(7):284-307
12.
Summary
Chlorella vulgaris UTEX259 was cultivated using two different methods of gas supply. In one method the CO2 concentration in bubbled gas was held constant and in the other method it was increased gradually. Algal growth was almost linear after a short period of lag phase in both methods. With the constant CO2 concentration, the CO2 fixation rate in the linear growth phase decreased over 10%(v/v) CO2, while the rate increased up to 6% CO2. However, the rate was enhanced by using the latter incremental increase method, especially under a higher concentration of CO2. The maximum rate of CO2 fixation was 52 mg CO2/l·h at 20% CO2 during the gradual increase of CO2 concentration. 相似文献
13.
The presence of Ca2+-ATPase activities with high-affinity sites for Ca2+ in brush border as well as basolateral plasma membranes of rat duodenal epithelium has been reported previously (Ghijsen, W.E.J.M. and van Os, C.H. (1979) Nature 279, 802–803). Since both plasma membranes contain alkaline phosphatase (EC 3.1.3.1), which also can be stimulated by Ca2+, the substrate specificity of Ca2+-induced ATP-hydrolysis has been studied to determine whether or not alkaline phosphatase and Ca2+-ATPase are two distinct enzymes. In basolateral fragments, the rate of Ca2+-dependent ATP-hydrolysis was greater than that of ADP, AMP and at Ca2+ concentrations below 25 μM. At 0.2 mM Ca2+ the rates of ATP, ADP, AMP and hydrolysis were not significantly different. In brush border fragments the rates of ATP, ADP and AMP hydrolysis were identical at low Ca2+, but at 0.2 mM Ca2+, Ca2+-induced hydrolysis of ADP and AMP was greater than either ATP or . Alkaline phosphatase in brush border and basolateral membranes was inhibited by 75% after addition of 2.5 mM theophylline. Ca2+-stimulated ATP hydrolysis at 1 μM Ca2+ was not sensitive to theophylline in basolateral fragments while the same activity in brush border fragments was totally inhibited. At 0.2 mM Ca2+, Ca2+-induced ATP hydrolysis in both basolateral and brush border membranes was sensitive to theophylline. Oligomycin and azide had no effect on Ca2+-stimulated ATP hydrolysis, either at low or at high Ca2+ concentrations. Chlorpromazine fully inhibited Ca2+-stimulated ATP hydrolysis in basolateral fragments at 5 μM Ca2+, while it had no effect in brush border fragments. From these results we conclude that, (i) Ca2+-ATPase and alkaline phosphatase are two distinct enzymes, (ii) high-affinity Ca2+-ATPase is exclusively located in basolateral plasma membranes, (iii) alkaline phosphatase activity, present on both sides of duodenal epithelium, is stimulated slightly by low Ca2+ concentrations, but this Ca2+-induced activity is inhibited by theophylline and shows no specificity with respect to ATP, ADP or AMP. 相似文献
14.
Summary A large pedigree with a satellited Yq chromosome is described, Q, C, and NOR banding were performed. Family C proband suffers from a Klinefelter syndrome. 相似文献
15.
G J Hughes C de Jong R W Fischer K H Winterhalter K J Wilson 《The Biochemical journal》1981,199(1):61-67
Native rat haemoglobins were found to bind simetryn sulphoxide to an extent 40-fold greater than human haemoglobin. This specific behaviour was studied by using only high-pressure ('performance') liquid chromatography for the preparative separation of globin chains and the isolation of peptides resulting from chemical and enzymic degradation. High recoveries (greater than 80%) of peptides throughout the procedures in combination with microsequence techniques, allow a definitive assignment of the residue undergoing modification. The haemoglobin beta-chain cystine-125 residue, with a stoichiometry of one per tetramer of rat haemoglobin, was found to be modified. Stereochemical implications of this finding are discussed. Simetryn sulphoxide would appear to be useful as a specific reagent for the mapping of exposed thiol residues in proteins. 相似文献
16.
The present report describes two female siblings of mixed ancestry (Cape Coloured) with consanguineous parents as further examples of Cross oculocerebral hypopigmentation syndrome. The mixed pattern of hair pigmentation as an important diagnostic sign is emphasized. 相似文献
17.
To consider possible interaction of the phospholipid membrane with calcium ions, crystal structures of calcium dl-alpha- and beta-glycerophosphates (alpha- and beta-CaGs, respectively) were investigated by X-ray diffraction methods. After many attempts, relatively large single crystals of beta-CaG were prepared from the aqueous solution containing HCl, while crystals of CaHPO4.2H2O were obtained from alpha-CaG solution under the same crystallization conditions. The crystal structure of beta-CaG is orthorhombic with space group Pna2(1) and cell dimensions of a = 8.251(1), b = 13.038(3), c = 25.483 (10) A, V = 2741.5 (13) A3 and Z = 16 [four molecules (A to D) in an asymmetric unit]. Molecules of A to D took, as a whole, similar extended conformations, although A and B were different from C and D in the orientation about a glycerol C-C bond. Four independent beta-glycerophosphates commonly act as two types of bidentate ligands, where one is the coordination to the calcium ion by the glycerol O(1) and phosphate O(22) atoms, and the other by the phosphate O(22) and O(23) atoms, thus forming the calcium coordination of a distorted square plane, respectively. Each of four independent calcium ions forms the same coordination geometry of a distorted pentagonal bipyramid. Infinite double layers consisting of alternate A/B molecules and of alternative C/D ones and sandwiching calcium ions were arranged face-to-face along the b-direction and were piled up in the a-direction, thus forming the stacked bilayer unit with the thickness of d002 = 12.75 A. The elaborate networks of calcium coordinations and hydrogen bondings were formed among the layers and stabilized the crystal structure. Based on the structural parameters of the present beta-CaG crystal, a possible interaction model of phospholipid with calcium ions was proposed. 相似文献
18.
X-ray crystallographic conformational study of 5'-O-[N-(L-alanyl)-sulfamoyl]adenosine, a substrate analogue for alanyl-tRNA synthetase 总被引:2,自引:0,他引:2
H Ueda Y Shoku N Hayashi J Mitsunaga Y In M Doi M Inoue T Ishida 《Biochimica et biophysica acta》1991,1080(2):126-134
In order to elucidate the substrate specificity of alanyl-tRNA synthetase, 5'-O-[N-(L-alanyl)sulfamoyl]adenosine (Ala-SA), an analogue of alanyl-AMP, was chemically synthesized. Its binding ability is similar to that of the substrate based on the inhibitory activity for the aminoacylation of alanyl-tRNA synthetase. Taking advantage of the stable sulfamoyl bond of Ala-Sa, compared with the highly labile aminoacyl bond of alanyl-AMP, the molecular conformation of the former inhibitor was studied by X-ray single crystal analysis. Crystal data are as follows: C13H19N7O7S.2H2O, space group C2, a = 39.620(6), b = 5.757(1), c = 20.040(3) A, beta = 117.2(1) degrees, V = 4065(9) A3, Z = 8, and final R = 0.065 for 2785 independent reflections of F(2)0 greater than or equal to 2 sigma (F0)2. In the crystal, the molecule is in a zwitterionic state with the terminal amino group protonated and sulfamoyl group deprotonated, and takes an open conformation, where the L-alanine moiety is located far from the adenosine moiety with gauche/trans and trans orientations about the exocyclic C(4')-C(5') and C(5')-O(5') bonds, respectively. The conformation of the adenosine moiety is anti for the glycosyl bond and C(3')-endo for the ribose puckering, and alanine is in the usually observed trans region for the psi torsion angle. The molecular dimensions of the sulfamoyl group are nearly the same as those of the phosphate group. The biological significance of the observed Ala-SA conformation is discussed in relation with the molecular conformation of tyrosyl-AMP complexed with tyrosyl-tRNA synthetase. 相似文献
19.
Wilfried W. de Jong Louis H. Cohen Jack A.M. Leunissen Anneke Zweers 《Biochemical and biophysical research communications》1980,96(2):648-655
αAIns, an elongated α-crystallin A chain previously observed in rat, was present beside the normal αA chain in mouse, gerbil and hamster, which places its origin at least 30 million years ago. Like in rat the sequences of golden hamster αAIns and αA were found to be identical, apart from the internal insertion of 22 residues in αAIns. The hamster chains only differed from the rat chains by a single substitution in the inserted sequence of αAIns. The origin of αAIns, by insertion of 22 residues in an otherwise unchanged αA chain, and its rigid evolutionary conservation are most easily explained by assuming the incomplete removal of a putative intervening sequence from the precursor mRNA of αA, leaving an intracistronic insert of 66 nucleotides in part of the eventually translated mRNA. 相似文献
20.
More than 300 reference strains representing 60 species and varieties ofFusarium cultures named according to different taxonomic systems are currently maintained at the American Type Culture Collection (ATCC). They have been preserved by freeze-drying and by freezing and subsequent storage in liquid nitrogen (–196°C) to insure their viability without contamination, variation, mutation, or deterioration. The materials and procedures used at the ATCC for the acquisition, accessioning, cataloguing, preservation and distribution are described. Longevity storage data for the strains available for distribution are presented and discussed. 相似文献