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811.
Tsutomu Ushijima 《Microbiology and immunology》1969,13(1):51-63
The cell division of a strain of Bacteroides convexus was examined by the ultrathin sectioning and the electron microscopy. The cell division was initiated by the invagination of the cytoplasmic membrane from the opposite sites at the middle of the cell. The constriction of the cell wall also occurred simultaneously or soon after the initiation of the invagination of the cytoplasmic membrane. A short septum structure similar to those of gram positive bacteria originated within the base of mesosome. The two mesosomes arising from the opposite sites fused at the center of the cell. After the tips of invaginating outer membrane reached to the middle between cell center and original outer membrane, the mesosomes were reduced gradually and finally disappeared. In this stage of the cell division, a transverse septum was usually completed. The invagination of the outer membrane proceeded progressively and finally fused at the center of the division plane. 相似文献
812.
813.
814.
Morio Ikehara Toshikazu Fukui 《Biochimica et Biophysica Acta (BBA)/General Subjects》1974,338(2):512-519
Several synthetic adeonosine analogs: 8-fluoro-, 8-azido-, 8-iodo-, 8-methylthioadenosine; 8-bromo-2′-deoxyadenosine, 8-bromoxylofuranosyladenine, 5′-benzoly-8-bromoadenosine; 8,2′-S-, 8,2′-O-, 8,2′-NH-, 8,2′-N-CH3-, 8,3′,-S-, 8,3′-O-, 8,5′-S- and 8,5′O-cycloadenosine; 1-deaza- and 3-deazaadenosine, as well as tubercidine (7-deazaadenosine), were tested as substrates of calf intestine adenosine deaminase.It was found that the adenine base of adenosine should be in the range φrmCN = 0–120° (anti to syn-anti) and 8-fluoroadenosine was hydroylzed very slowly. The purine base should have N1, N3 or N7 atoms for the hydrolysis and only 1-deazaadenosine revealed an inhibitory effect toward the hydrolysis of adenosine.5′-OH group should be in the position of S-configuration and must not be substituted. 相似文献
815.
This paper is concerned with new findings in the comparative study of the genera, Bacteroides, Sphaerophorus and Fusobacterium. Victoria blue 4R and barbiturates were found to be effective in differentiating the genera by their discriminative inhibition of the growth. A new character, glutamic acid decarboxylation, was found in Bacteroides but neither in Sphaerophorus nor in Fusobacterium. The procedure for this test was presented. In the classification of newly isolated fecal strains this test and other differential features were compared. An improved method for the threonine deamination test was reported. The use of these characters and tests would be a step in the improvement of the present incomplete classification of gram-negative anaerobic non-sporulating rods. 相似文献
816.
Amanda Shore-Maggio Christina M. Runyon Blake Ushijima Greta S. Aeby Sean M. Callahan 《Applied and environmental microbiology》2015,81(20):7312-7318
Corals harbor diverse bacterial associations that contribute to the health of the host. Using 16S rRNA pyrosequencing, we compared the bacterial communities of red and orange morphs of the Hawaiian coral Montipora capitata. Although both color morphs shared dominant bacterial genera, weighted and unweighted UniFrac analyses showed distinct bacterial communities. A single operational taxonomic unit (OTU), classified as Vibrio, represented the largest driver of differences between the color morphs. This OTU comprised 35.4% (±5.5%) of the orange morph bacterial community yet comprised 1.1% (±0.6%) of the red morph bacterial community. Cultivable bacteria from the two color morphs were also compared and tested for antibacterial activity. Cultured isolates represented 14 genera (7% of the total genera identified from sequencing data), and all but two cultured isolates had a matching OTU from the sequencing data. Half of the isolates tested (8 out of 16) displayed antibacterial activity against other cultured isolates but not against two known bacterial pathogens of M. capitata. The results from this study demonstrate that the specificity of coral-bacterial associations extends beyond the level of coral species. In addition, culture-dependent methods captured bacterial diversity that was representative of both rare and abundant members of the associated bacterial community, as characterized by culture-independent methods. 相似文献
817.
Tomokazu Ushijima Hiroaki Matsusaka Hiroyuki Jikuya Masahiro OgawaHikaru Satoh Toshihiro Kumamaru 《Plant science》2011,181(2):125-131
The esp1 mutant CM21 specifically exhibits reduced levels of cysteine-poor (CysP) prolamin bands with pIs of 6.65, 6.95, 7.10, and 7.35 in rice seed. Matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis demonstrated that the bands with pIs 6.65, 6.95, and 7.35 are encoded by different structural genes. These results suggest that the Esp1 locus encodes a regulatory factor involved in the synthesis and/or accumulation of CysP prolamin molecules. Isoelectric focusing (IEF) analysis of CysP prolamins in chromosome substitution lines showed that structural genes for bands with pI values of 6.95, 7.10, and 7.35, which are reduced in esp1 mutant lines, are located as a gene cluster in the 44.2 cM region on chromosome 5. 相似文献
818.
Cyclotella ortentalis sp. nov, is described from an epilithic sample taken in Lake Imha, located in Kyungsangbuk-do. South Korea. The species is characterized by a conspicuous and short costa regularly extending from each marginal fultoportula to the valve margin. It can be included in the Cyclotella stelligeroid group. The new species can be separated from the most similar species C. stelligera Cleve et Grunov var. stelligera by the more distant position of marginal fultoportulae from the valve margin, the external long tubes of fultoportulae and having short costae. It differs from C. stelligera var. robusta Must, and var. hyalina Hust., in having much denser marginal striae; from C. glomerata H. Bachm., C. pseudostelligera Hust., C. stelligeroides Must, and C. woltereckii Hust., in its much larger valve, coarser marginal striae and short costae with fultoportulae. 相似文献
819.
Data are presented which indicate that combinations of rCD4 immunoglobulin with azidothymidine, dideoxyinosine or 0.5 β mouse monoclonal antibodies directed against the V3 region of HIV-1, were more effective in treatment of acute HIV infection in vitro than each compound alone. It is suggested that combination therapy with these compounds is more beneficial in treatment of HIV-infected patients than monotherapy, especially with respect to a reduction of the known side effects and the formation of resistant HIV strains after treatment with nucleoside analogues. 相似文献
820.
Toshikazu Makino 《Microbiology and immunology》1983,27(9):749-755
Protoplasts of Staphylococcus aureus 209P and Cowan 1 were induced by treatment with lysostaphin. These protoplasts were sensitive to detergent, a low concentration of sodium chloride and low temperature. Almost all protoplast cells spread on CLYS agar medium (casein hydrolysate, yeast extract, Na-lactate, and NaCl) formed typical L-form colonies. Horse serum (0.25%) and Mg2+ (109 mm) are essential factors for formation of the L-form colonies of 209P. In the case of Cowan 1, Mg2+ was not required. The active factor(s) in horse serum was heat-resistant and protein in nature. 相似文献