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排序方式: 共有1620条查询结果,搜索用时 15 毫秒
1.
Production of vitamin B12 in an upflow anaerobic filter continuous reactor using Acetobacterium sp. 总被引:2,自引:0,他引:2
Alberto Emilio Bainotti Belén Estebanez Hisashi Nagadomi Naomichi Nishio 《Biotechnology letters》2000,22(6):503-508
The accumulation of biofilm by Acetobacterium sp. during continuous culture in an upflow anaerobic filter (UAF) growing on methanol-formate was the result of space velocity and inlet concentrations of substrate and Co+2. To achieve good development of biofilm, a space velocity of 0.38 h–1, inlet substrate concentrations of 125 mM of both methanol and formate, and Co+2 at 0.16 mM were required. Cell productivities in the effluent of the UAF-reactor were about 6-fold higher than in chemostat cultures (0.20 g l–1 h–1 for UAF and 0.035 g l–1 h–1 for chemostat) (previous studies), and the maximum vitamin B12 specific concentration was 5.1 mg g cell–1. 相似文献
2.
Wakae Fujimaki Keiko Baba Katsunori Tatara Ryohji Umezu Sanji Kusakawa Yasushige Mashima 《Human genetics》1987,76(3):302-302
Summary A case of ring chromosome 15 passed on to the index patient's two children is reported, and possible reasons for the infrequent records of inheritance of ring chromosome are suggested. 相似文献
3.
Background
A reliable extraction technique for resolving multiple spots in light or electron microscopic images is essential in investigations of the spatial distribution and dynamics of specific proteins inside cells and tissues. Currently, automatic spot extraction and characterization in complex microscopic images poses many challenges to conventional image processing methods. 相似文献4.
The presence of the t haplotypes in strains derived from the Japanese wild mice (Mus musculus molossinus) was investigated. Crosses between the T/+ heterozygous short tailed mice and five normal tailed molossinus strains (MOL-ANJ, MOA, MOL-NEM, MOM and Mns) produced no tailless mice, indicating that these strains possess no t haplotype. In contrast, tailless mice were produced by a cross between the T/+ heterozygotes and a MOL-NIS strain. Mating experiments showed that the tailless character was due to an interaction between the T gene and an autosomal recessive gene carried by the MOL-NIS strain that expresses the short tail character under the homozygous condition. We have tentatively named this gene brachyury-interacting tail length modifier (btm). It remains to be investigated whether the btm gene is located in the t complex region or in the other locus. 相似文献
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AMP was phosphorylated by inorganic phosphorylating agents: cyclo-triphosphate and diphosphonate, in aqueous solution (70-80 degrees C, pH 6-12). The molecular structures of phosphorylated products were established by use of phosphorus-31 NMR and high-performance liquid chromatography (HPLC). The OH groups on AMP were phosphorylated by both phosphorylating agents to form 2'- or 3'-phosphate but an OH group on dAMP was not phosphorylated. Phosphorylation of OH group proceeds in two steps: formation of hydrogen bond between OH group and phosphorylating agent; subsequent nucleophilic attack of OH group on a phosphorus atom. Phosphate group on AMP was phosphorylated by diphosphonate but not by cyclo-triphosphate. The difference in the reactivities is explained in terms of charge repulsion between AMP and agents. 相似文献
9.
H. Ueda Takeshi Baba Nobuo Terada Yasuko Kato Shigeo Tsukahara Shinichi Ohno 《Histochemistry and cell biology》1997,108(3):243-248
It is known that the retina contains the protein dystrophin in the ribbon synapse, but the ultrastructural analysis is not
yet fully elucidated. Our previous study reported that dystrophin is localized under the rod cell membranes in rat retinas.
In the present study, we have investigated the relationship between dystrophin-rich regions of rod cell membranes and other
neuronal processes in mouse retinas with a monoclonal antibody raised against the human dystrophin C-terminus. Immunoblotting,
immunofluorescence stainings, and immunoelectron microscopy were employed. Immunoblotting analysis indicated that mouse retinas
possessed some of the dystrophin isoforms of approximately 260 kDa, 140 kDa, and 70 kDa molecular weight. Confocal images
showed a punctate appearance in the outer plexiform layer, as previously described. Immunoelectron microscopy showed that
dystrophin immunoreactive products were always observed at submembranous dense regions of the rod spherule abutting bipolar
processes. These results suggest that retinal dystrophin may be closely involved in signal transmission from rods to bipolar
cells.
Accepted: 7 May 1997 相似文献
10.
K. Hamada S. Fukuchi M. Arisawa M. Baba K. Kitada 《Molecular & general genetics : MGG》1998,258(1-2):53-59
Open reading frames in the genome of Saccharomyces cerevisiae were screened for potential glycosylphosphatidylinositol (GPI)-attached proteins. The identification of putative GPI-attached
proteins was based on three criteria: the presence of a GPI-attachment signal sequence, a signal sequence for secretion and
a serine- or threonine-rich sequence. In all, 53 ORFs met these three criteria and 38 were further analyzed as follows. The
sequence encoding the 40 C-terminal amino acids of each was fused with the structural gene for a reporter protein consisting
of a secretion signal, α-galactosidase and a hemagglutinin (HA) epitope, and examined for the ability to become incorporated
into the cell wall. On this basis, 14 of fusion proteins were classified as GPI-dependent cell wall proteins because cells
expressing these fusion proteins: (i) had high levels of α-galactosidase activity on their surface; (ii) released significant
amounts of the fusion proteins from the membrane on treatment with phosphatidylinositol-specific phospholipase C (PI-PLC);
and (iii) released fusion proteins from the cell wall following treatment with laminarinase. Of the 14 identified putative
GPI-dependent cell wall proteins, 12 had novel ORFs adjacent to their GPI-attachment signal sequence. Amino acid sequence
alignment of the C-terminal sequences of the 12 ORFs, together with those of known cell wall proteins, reveals some sequence
similarities among them.
Received: 1 September 1997 / Accepted: 20 November 1997 相似文献