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81.
Srinivas Ramisetti Hyun Ah Kang Sang Ki Rhee Chul Ho Kim 《Biotechnology and Bioprocess Engineering》2003,8(3):183-186
The artificial gene coding for anticoagulant hirudin was placed under the control of theGAL10 promoter and expressed in the galactokinase-deficient strain (Δgal1) ofSaccharomyces cereivisiae, which uses galactose only as a gratuitous inducer in order to avoid its consumption. For efficient production of recombinant
hirudin, a carbon source other than galactose should be provided in the medium to support growth of the Δgal1 strain. Here we demonstrate the successful use of glucose in the fed-batch fermentation of the Δgal1 strain to achieve efficient production of recombinant hirudin, with a yield of up to 400 mg hirudin/L. 相似文献
82.
Ken-Ichi Nunami Mamoru Suzuki Kazuo Matsumoto Naoto Yoneda Kazuo Takiguchi 《Bioscience, biotechnology, and biochemistry》2013,77(4):1073-1075
We investigated GroEL substrates from Bacillus subtilis 168 using the single-ring mutant of B. subtilis GroEL. We identified 28 candidates for GroEL substrates, of which Spo0B, Ald, Eno, SpoIIP, and FbaA were involved in spore formation, and Rnc, Tuf, Eno, Tsf, and FbaA were essential for B. subtilis growth. As observed at the protein level, the amount of SpoIIP interaction with GroEL increased at 3 h after initiation of sporulation. 相似文献
83.
Recently, negative effects of phosphatase in tumorigenesis and metastasis have been suggested in various tumor types. In this study, we showed that RhoA activation modulated phosphatase during senescence-like arrest in human prostate cancer cells. Under senescence-inducing condition, decreased Erk phosphorylation was detected in caRhoA-transfected cells and inactivation of Erk, but not p38, prevented doxorubicin-induced cell senescence. Cells were induced to senescence by inhibition of phosphatase activity (VHR, MKP3, or PP2A) without additional cellular stress. Of interest, caRhoA prevented doxorubicin-induced decrease of phosphatase. Thus, we postulate that RhoA signaling may protect cells against cellular senescence by maintaining phosphatase activity and Erk dephosphorylation. 相似文献
84.
Plaunotol was tested for possible antibacterial activity against twenty strains of methicillin-resistant Staphylococcus aureus (MRSA) and fourteen strains of methicillin-sensitive S. aureus (MSSA) which had been isolated from the skin of patients with atopic dermatitis under growth-promoting conditions. Plaunotol was effective against all strains tested. The dose of plaunotol for 50% inhibition of growth (ID50) ranged from 2.5 to 16 micrograms/ml for strains of MRSA and from 2.5 to 7.0 micrograms/ml for those of MSSA. These results suggest that plaunotol may be useful in the prevention of infection by MRSA and in skin care for patients with atopic dermatitis. 相似文献
85.
Makaoto Goto Osamu Imamura Junro Kuromitsu Takehisa Matsumoto Yukako Yamabe Yoshiki Tokutake Noriyuki Suzuki Brian Mason Dennis Drayna Minoru Sugawara Masanobu Sugimoto Y. Furuichi 《Human genetics》1997,99(2):191-193
The profile of helicase gene mutations was studied in 89 Japanese Werner’s syndrome (WRN) patients by examining the previously
described mutations 1– 4 as well as a new mutation found during this study, designated mutation 5. Of 178 chromosomes (89
patients), 89 chromosomes (50%) had mutation 4, 11 (6.2%) chromosomes had mutation 1, and two chromosomes (1.1%) contained
mutation 5. Mutations 2 and 3 were not observed in this patient population. The remaining 76 (42.7%) chromosomes had none
of these mutations. A significant fraction of all patients (22 total patients, 24.7%) appear to be compound heterozygotes,
including those carrying mutations of both types 1 and 4. The genotype analysis of the markers surrounding the WRN helicase gene strongly suggests that most of the chromosomes carrying either mutation 1 or 4 were derived from two single
founders.
Received: 25 July 1996 / Revised: 20 September 1996 相似文献
86.
87.
Catecholamine release from chromaffin cells in response to carbamylcholine and high K+ is transient. Monitoring intracellular free calcium ([Ca2+]i) using quin2 demonstrated a transient rise in [Ca2+]i in response to carbamylcholine. The termination of secretion due to carbamylcholine is probably a consequence of the return of [Ca2+]i to resting levels as the nicotinic receptors desensitise. Depolarisation with 55 mM K+ led to a long-lasting rise in [Ca2+]i which persisted after the secretory response had terminated. The maintained rise in [Ca2+]i appeared to be due to continued opening of verapamil-sensitive Ca2+ channels. These results suggest that inactivation of voltage-dependent Ca2+ channels does not account for the transient nature of the secretory response in chromaffin cells. 相似文献
88.
M Matsumoto K Iwamasa P D Rennert T Yamada R Suzuki A Matsushima M Okabe S Fujita M Yokoyama 《Journal of immunology (Baltimore, Md. : 1950)》1999,163(3):1584-1591
Both lymphotoxin-alpha (LTalpha)-deficient mice and alymphoplasia (aly) mice, a natural mutant strain, manifest a quite similar phenotype: lack of lymph nodes (LN) and Peyer's patches (PP), with disturbed spleen architecture. The mechanisms underlying the defective lymphoid organogenesis in these mice were investigated by generating aggregation chimeras; ex vivo fused morulae were implanted into pseudo-pregnant host females and allowed to develop to term. Chimeric mice between LTalpha-deficient mice and wild-type mice restored LN and PP almost completely, suggesting that LTalpha expressed by circulating bone marrow-derived cells is essential for lymphoid organogenesis as well as for organization of spleen architecture. By contrast, chimeric mice between aly mice and wild-type mice showed only limited restoration of LN and PP. This suggests that the putative aly gene product does not act as a circulating ligand for lymphoid organogenesis, like LTalpha. Rather, abnormal development of lymphoid organs in aly mice seems most likely due to the defective development of the incipient stromal cells of the LN and PP. Supporting this hypothesis, up-regulation of VCAM-1 on aly mouse embryonic fibroblasts by signals through LTbetaR, which is exclusively expressed by nonlymphoid cells, was disturbed. These studies demonstrate that LTalpha and the putative aly gene product together control lymphoid organogenesis with a close mechanistic relationship in their biochemical pathways through governing the distinct cellular compartments, the former acting as a circulating ligand and the latter as a LTbetaR-signaling molecule expressed by the stroma of the lymphoid organs. 相似文献
89.
90.
Ahmed H.E. Hassan Min Chang Cho Hye In Kim Ji Seul Yang Kyung Tae Park Ji Young Hwang Choon-Gon Jang Ki Duk Park Yong Sup Lee 《Bioorganic & medicinal chemistry》2018,26(18):5069-5078
CRA13; a peripheral dual CB1R/CB2R agonist with clinically proven analgesic properties, infiltrates into CNS producing adverse effects due to central CB1R agonism. Such adverse effects might be circumvented by less lipophilic compounds with attenuated CB1R affinity. Metabolism produces less lipophilic metabolites that might be active metabolites. Some CRA13 oxidative metabolites and their analogues were synthesized as less lipophilic CRA13 analogues. Probing their CB1R and CB2R activity revealed the alcohol metabolite 8c as a more potent and more effective CB2R ligand with attenuated CB1R affinity relative to CRA13. Also, the alcohol analogue 8b and methyl ester 12a possessed enhanced CB2R affinity and reduced CB1R affinity. The CB2R binding affinity of alcohol analogue 8b was similar to CRA13 while that of methyl ester 12a was more potent. In silico study provided insights into the possible molecular interactions that might explain the difference in the elicited biological activity of these compounds. 相似文献