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61.
NG, a strain of cultured tobacco cells of Nicotiana glutinosahad high growth rates and carboxylate contents (CA) of100 to 130 meq/100 g of dry cells on media containing 42 meqNO3/liter as the sole N source. (CA) is the amount ofinorganic cations minus inorganic anions in meq per 100 g ofdry cells. NG, cultured on media containing NH4 10+NO3 42 in meq/liter,had lower growth rates and lower (CA) values as comparedwith NG on media containing NO3 as the sole N source. NG, cultured on media containing NH4 30+NO3 42 in meq/liter,had high growth rates and (AC) values of 22 to 53 meq/100gof dry cells. In this case, the (AC) content may correspondto organic cations, basic organic N compounds such as free asprotein-bound basic amino acids. The easily absorbed Cl mayhave been required maintain good growth conditions such as ionicbalance and a favorable pH in the cells. Thus cultured cells of Nicotiana glutinosa may have physiologicaladaptability against variations in a relatively wide range of|CA| contents [|CA| being the absolute valuesof (CA)]. (Received May 15, 1980; ) 相似文献
62.
Noriyuki Muranushi Noriko Takagi Shozo Muranishi Hitoshi Sezaki 《Chemistry and physics of lipids》1981,28(3):269-279
The effect of fatty acids and monoglycerides on barrier properties of liposomal membranes prepared from egg phosphatidylcholine was investigated. The incorporation of these lipids as liposomal membrane components induced the alteration of the permeability to less permeable liposomally entrapped drugs, sulfanilic acid and procainamide ethobromide (PAEB). Monoolein caused greatly increased permeability of both drugs and unsaturated fatty acids markedly enhanced the release rate of PAEB, while saturated fatty acids caused a small increase in the release rate.Electron spin resonance (ESR) investigation with 5-nitroxide stearic acid showed that fatty acids disordered the hydrophobic region of the lipid bilayer and the disordering effect of unsaturated fatty acids was greater than that of saturated ones. It was demonstrated that the incorporated fatty acids and monoglycerides interacted with the polar region of the membranes by ESR study with cholestane label and 1H-NMR study. These results indicated that the increase in the membrane permeability caused by fatty acids and monoglycerides associated with the disorder in the membranes' interior and the interaction of the incorporated lipid with the polar head group of phospholipid. 相似文献
63.
Hitoshi Iizumi Akihiko Hattori C.P. McRoy 《Journal of experimental marine biology and ecology》1980,47(2):191-201
The distribution of nitrate and nitrite in the interstitial water of the sediment of eelgrass (Zostera marina) bed of Izembek Lagoon, Alaska, were investigated. Their concentrations were relatively high (0 to 9.8 μg-at.N·1?1, average 4.8 for nitrate; 0 to 4.0 μ-at.N·1?1, average 1.9 for nitrite) although the sediments were anoxic and contained hydrogen sulphide. The rates of bacterial denitrification measured by 15N tracer technique ranged from 0.49×10?10 to 1.2 × 10?9 g-atN·g?1·h?1. When a steady state is maintained, the loss of nitrate and nitrite must be balanced by their production by bacterial nitrification. Experimentally determined rate of nitrification in the sediment was of the same order. A model experiment demonstrated that oxygen is transported from leaves to rhizomes and roots of eelgrass and released into the sediment. The oxygen is used for nitrification in the rhizosphere in anoxic sediments. 相似文献
64.
- When applying the adsorption theory to the selectivity coefficient,K and Mg uptakes by cells in a K-Mg replacement series of mediaare not regulated only by a common mechanism, under the assumptionthat b values, which indicate the affinities between the ionand the adsorptive surface, do not change.
- Regulation of Kand Mg uptakes by a common multiphasic mechanismin the cellsis possible when the selectivity coefficient bK/bMgvaries inverselywith the MK/MMg ratio in the external medium.
- K and Mg uptakesare not regulated only by their respectivesingle specific mechanisms.
- Another possibility is regulation of K and Mg uptakes bothbycommon and specific mechanisms. The common mechanism maybemultiphasic.
65.
Hitoshi Watanabe 《Journal of invertebrate pathology》1976,28(3):321-328
A microsporidian was isolated from the Egyptian cotton leafworm, Spodoptera litura, and was identified as a member of the genus Nosema since its sporont produced two spores. The size of the fresh spores was 3.3–4.5 × 1.7 – 2.2 μm. Mean length of the polar filaments was 90.7 μm. In addition to the Egyptian cotton leafworm, this microsporidian was also infectious to Pieris rapae crucivora, Hyphantria cunea, Chilo suppressalis, Agrotis ipsilon, and Adoxophyes orana. Although the parasite ultimately caused generalized infection in the Egyptian cotton leafworm larva, the main site of infection was the adipose tissue. 相似文献
66.
A PC survey revealed the occurrence of an unusual amino acid in fruit bodies of the mushroom Lactarius quietus Fr. and a related species. This was identified as l-2-amino-4-methylpimelic acid, which has not been previously reported as a naturally occurring compound. 相似文献
67.
Daniel Evans-Yamamoto Franois D Rouleau Piyush Nanda Koji Makanae Yin Liu Philippe
C Desprs Hitoshi Matsuo Motoaki Seki Alexandre K Dub Diana Ascencio Nozomu Yachie Christian
R Landry 《Nucleic acids research》2022,50(9):e54
Barcode fusion genetics (BFG) utilizes deep sequencing to improve the throughput of protein–protein interaction (PPI) screening in pools. BFG has been implemented in Yeast two-hybrid (Y2H) screens (BFG-Y2H). While Y2H requires test protein pairs to localize in the nucleus for reporter reconstruction, dihydrofolate reductase protein-fragment complementation assay (DHFR-PCA) allows proteins to localize in broader subcellular contexts and proves to be largely orthogonal to Y2H. Here, we implemented BFG to DHFR-PCA (BFG-PCA). This plasmid-based system can leverage ORF collections across model organisms to perform comparative analysis, unlike the original DHFR-PCA that requires yeast genomic integration. The scalability and quality of BFG-PCA were demonstrated by screening human and yeast interactions for >11 000 bait-prey pairs. BFG-PCA showed high-sensitivity and high-specificity for capturing known interactions for both species. BFG-Y2H and BFG-PCA capture distinct sets of PPIs, which can partially be explained based on the domain orientation of the reporter tags. BFG-PCA is a high-throughput protein interaction technology to interrogate binary PPIs that exploits clone collections from any species of interest, expanding the scope of PPI assays. 相似文献
68.
Genetic variations in humans associated with differences in the course of hepatitis C 总被引:6,自引:0,他引:6
Saito T Ji G Shinzawa H Okumoto K Hattori E Adachi T Takeda T Sugahara K Ito JI Watanabe H Saito K Togashi H Ishii K Matsuura T Inageda K Muramatsu M Kawata S 《Biochemical and biophysical research communications》2004,317(2):335-341
The outcome of hepatitis C virus (HCV) infection varies among individuals, but the genetic factors involved remain unknown. We conducted a population-based association study in which 238 Japanese individuals positive for anti-HCV antibody were genotyped for 269 single nucleotide polymorphisms (SNPs) in 103 candidate genes that might influence the course of infection. Altogether, 50 SNPs in 32 genes were listed. Genetic polymorphisms in IL4, IL8RB, IL10RA, PRL, ADA, NFKB1, GRAP2, CABIN1, IFNAR2, IFI27, IFI41, TNFRSF1A, ALDOB, AP1B1, SULT2B1, EGF, EGFR, TGFB1, LTBP2, and CD4 were associated with persistent viremia (P < 0.05), whereas those in IL1B, IL1RL1, IL2RB, IL12RB1, IL18R1, STAT5A, GRAP2, CABIN1, IFNAR1, Mx1, BMP8, FGL1, LTBP2, CD34, and CD80 were associated with different serum alanine aminotransferase levels in HCV carriers (P < 0.05). The sorted genes allow us to draw novel hypotheses for future studies of HCV infection to ultimately identify bona fide genes and their variations. 相似文献
69.
KIT (c-kit oncogene product) pathway is constitutively activated in human testicular germ cell tumors 总被引:5,自引:0,他引:5
Nakai Y Nonomura N Oka D Shiba M Arai Y Nakayama M Inoue H Nishimura K Aozasa K Mizutani Y Miki T Okuyama A 《Biochemical and biophysical research communications》2005,337(1):289-296
We investigated the expression of KIT (product of c-kit oncogene), gain-of-function mutations, and activation of its downstream signal transduction in human testicular cancers. KIT was expressed in 88% (22/25) of seminomas and in 44.4% (4/9) of non-seminomas compared to adjacent normal testicular tissue. Nine of the KIT-expressing seminomas had mutations (40.9%; 9/22) in the c-kit gene; two cases in exon 11 and 7 cases in exon 17. Two of these mutations in exon 17 were novel, and the other seven mutations were identical to the already known gain-of-function mutations which cause activation of KIT without ligand stem cell factor. All of the mutant KIT and 53.8% (7/13) of wild-type KIT were phosphorylated (activated) and associated with phosphorylated phosphatidylinositol 3-kinase (PI3K). Akt was also phosphorylated in these seminomas, suggesting that the KIT-PI3K-Akt pathway is activated in seminoma. These findings suggest that the KIT-PI3K-Akt pathway is constitutively activated in testicular germ cell tumors, due to overexpression of KIT protein and/or gain-of-function mutations in the c-kit gene. 相似文献