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1.
《Bioscience, biotechnology, and biochemistry》2013,77(6):1270-1275
A bacterial strain, designated CY22, was isolated from the interior of balloon flower (Platycodon grandiflorum) root in the Republic of Korea. The isolate coproduced an iturin-like antifungal compound and a surfactin-like potent biosurfactant. Analysis of the 16S-rDNA of strain CY22 showed that the isolate was a member of Bacillus. High similarities were observed between strain CY22 and Bacillus sp. TKSP 24, and between strain CY22 and B. subtilis 168. Phylogenetic analysis based on 16S-rDNA sequences showed that strain CY22 was closely related to Bacillus sp. The main whole-cell fatty acids were anteiso-C15:0 (37%), C17:0 (5.1%), and iso-C15:0 (27.7%). DNA G + C content was 54 mol%. Based on phylogenetic inference, phenotypic and chemotaxonomic characteristics, this endophytic strain Bacillus sp. CY22 was assigned to the genus Bacillus. 相似文献
2.
Evangelia Jockers-Wretou Valya Russanova Christo Venkov 《Molecular biology reports》1988,13(3):123-131
In a recent publication the isolation and some characteristics of an anti-histone 3 monoclonal antibody, 1GB3 were described (Muller et al. FEBS Lett. 182: 459–464, 1985). We now report that the epitope recognized is phylogenetically conserved and located in the N-terminal part of H3, most likely between residues 40 and 50. Using the ELISA technique we found this region to be accessible in chromatin to the monoclonal antibody. The effect of non-ionic detergents on the adsorbtion of chromatin on microtiter plates was studied in this context.Immunological analysis of the reaction of the monoclonal antibody with chromatin by immunoinhibition and immunosedimentation shows that the H3 epitope is accessible in both folded and unfolded chromatin fibre as well as in high- and low-molecular weight oligonucleosomes.Abbreviations BSA
Bovine srum albumin
- mab
Monoclonal antibody
- PBS
Phosphate buffered saline
- PMSF
Phenylmethyl sulfonyl fluoride 相似文献
3.
(+)-2,9 alpha-Dimethyl-5-(m-hydroxyphenyl)morphan is the only phenylmorphan analog whose affinity for opioid kappa-receptors is greater than its affinity for opioid mu-receptors. Pharmacologically, the compound is a pure opioid antagonist devoid of agonist activity in in vivo assays of antinociception. The absolute configuration of the compound has been determined to be (1R,5S,9R) from an X-ray crystallographic study of the chloride salt. Thus, the absolute configuration corresponds to that of the atypical opioid agonist (-)-phenylmorphan while the weak atypical agonist (-)-2,9 alpha-dimethyl-5-(m- hydroxyphenyl)morphan corresponds to the potent morphine-like (+)-phenylmorphan. The preferred orientations of the phenyl ring for the two stereoisomers were determined using the molecular mechanics program MM2-87 and found to vary from that of the two parent compounds. The atypical properties of the two 9 alpha-methyl analogs is consistent with an opioid ligand model which proposes that morphine-like properties require a particular range of phenyl orientations. There was good agreement between the structure obtained from X-ray crystallography and computed with the MM2-87 program. 相似文献
4.
Peanut (Arachis hypogaea) agglutinin (PNA) is extensively used as tumour marker as it strongly recognises the cancer specific T antigen (Galβ1→3GalNAc-), but not its sialylated version. However, an additional specificity towards Galβ1→4GlcNAc (LacNAc), which is not tumour specific, had been attributed to PNA. For correct interpretation of lectin histochemical results we examined PNA sugar specificity using naturally occurring or semi-synthetic glycoproteins, matrix-immobilised galactosides and lectin-binding tissue glycoproteins, rather than mono- or disaccharides as ligands. Dot-blots, transfer blots or polystyrene plate coatings of the soluble glycoconjugates were probed with horse-radish peroxidase (HRP) conjugates of PNA and other lectins of known specificity. Modifications of PNA-binding glycoproteins, including selective removal of O-linked oligosaccharides and treatment with glycosidases revealed that Galβ1→4GlcNAc (LacNAc) was ineffective while terminal α-linked galactose (TAG) as well as exposed T antigen (Galβ1→3 GalNAc-) was excellent as sugar moiety in glycoproteins for their recognition by PNA. When immobilised, melibiose was superior to lactose in PNA binding. Results were confirmed using TAG-specific human serum anti-α-galactoside antibody. 相似文献
5.
《Bioscience, biotechnology, and biochemistry》2013,77(9):2472-2475
Conjugational transfer of pLS20 in Bacillus subtilis Marburg 168 is restricted by the BsuM restriction-modification system. Restriction efficiency was measured using pLS20 derivatives possessing various numbers of XhoI sites, which are known to be recognized by BsuM. An increase in XhoI sites clearly reduced the conjugational efficiency of pLS20 as compared with that of pUB110 plasmid lacking XhoI. 相似文献
6.
Defective transducing phages carrying aroG, the structural gene for phenylalanine (phe)-inhibitable phospho-2-keto-heptonate aldolase (EC 4.1.2.15; previously known as 3-deoxy-D-arabinoheptulosonate-7-phosphate synthetase[phe]), have been isolated, and DNA from two of these phages has been used to construct a restriction map of the region from att lambda to aroG. A 7.6-kb PstI-HindIII fragment from one of these phages was cloned into pBR322 and shown to contain aroG. The location of aroG within the 7.6 kb was established by subcloning and Tn3 transpositional mutagenesis. A fragment carrying the aroG promoter and operator has been cloned into a high copy number promoter-cloning vector (pMC489), and the resulting aroGpo-LacZ' (alpha) fusion subcloned in a low copy number vector. Strains with this fusion on the low copy number vector exhibit negative regulation of beta-galactosidase expression by both phenylalanine and tryptophan and positive regulation by tyrosine in a tyrR+ background. 相似文献
7.
8.
Sandrine Poncet Armelle Delecluse Guido Anello ré Klier Georges Rapoport 《FEMS microbiology letters》1994,117(1):91-95
Abstract The genes encoding the CryIVB and CryIVD crystal polypeptides of B. thuringiensis subsp. israelensis were cloned indepently on a stable shuttle vector, and transfered into B. sphaericus 2297. Recombinant cells expressed the B. thuringiensis toxins during sporulation and were shown to be toxic to Aedes aegypti fourth instar larvae, whereas the parental strain was not. 相似文献
9.
Steven J. Tucker David McClelland Kristina Sep?i? Roderick H. Scott 《生物化学与生物物理学报:生物膜》2003,1614(2):171-181
The ability of two alkyl pyridinium sponge toxin preparations (poly-APS and halitoxin) to form transient pores/lesions in cell membranes and allow transfection of plasmid cDNA have been investigated using HEK 293 cells. Poly-APS and halitoxin preparations caused a collapse in membrane potential, reductions in input resistance and increased Ca2+ permeability. At least partial recovery was observed after poly-APS application but recovery was more rarely seen with halitoxin. The transfection with plasmid cDNAs for an enhanced green fluorescent protein (EGFP) and human tumour necrosis factor receptor 2 (TNFR2) was assessed for both toxin preparations and compared with lipofectamine. Stable transfection was achieved with poly-APS although it was less efficient than lipofectamine. These results show that viable cells transfected with alien cDNA can be obtained using novel transient pore-forming alkyl pyridinium sponge toxins and a simple pre-incubation protocol. This provides the first proof of principle that pore-forming alkyl pyridinium compounds can be used to deliver cDNA to the intracellular environment without permanently compromising the plasma membrane. 相似文献
10.
Takemi Yoshida Akio Uchida Toshinori Yamamoto Yukio Kuroiwa 《Biochimica et Biophysica Acta (BBA)/General Subjects》1981,677(2):280-286
The activities of mitochondrial type A and B monoamine oxidase were determined in the liver of rats fed a diet containing 2-acetylaminofluorene (AAF). Three days after the initiation of AAF-feeding, there was a significant decrease of type B monoamine oxidase activity without affect on type A enzyme. The decreased activity of type B monoamine oxidase, which reached a minimum after three weeks, was sustained for as long as AAF-feeding was continued. Sex-related difference in response to AAF was seen in the rat with respect to the onset and the intensity of the decreased type B monoamine oxidase activity, male rats being more sensitive to the carcinogen than female rats. In contrast to the in vivo effect, AAF showed a potent inhibitory effect on type A monoamine oxidase, rather than on type B enzyme, when added in vitro. The pI50 values were estimated to be 7.5 against type A monoamine oxidase and 4.1 against type B enzyme, respectively. The in vitro inhibition of both types of monoamine oxidase by AAF was competitive. The Ki values for AAF were calculated to be 9.51 · 10?9 M for type A monoamine oxidase and 1.30 · 10?5 M for type B enzyme, respectively. In accordance with the potent inhibitory effect of AAF on type A monoamine oxidase in vitro, a single administration of the carcinogen, at a dose of 50 mg/kg, resulted in a marked and temporal decrease of the enzyme activity in the mitochondria of male rat liver. Recovery of the decreased type B monoamine oxidase activity was slow, and the enzyme activity did not return to control levels, even if rats were fed the basal diet for 2 or 4 weeks after the cessation of AAF-feeding. 相似文献