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951.
952.
Rickert Adriana Aranda Soria Marcelo Abel Correa Olga Susana 《World journal of microbiology & biotechnology》2000,16(5):475-480
Mesorhizobium huakuii strain LL56 and Mesorhizobium sp. strain LL22, which nodulate Lotus glaber, developed an adaptive acid response during exponential growth upon exposure to sublethal acid conditions. The adaptive acid response was found to be dependent on the sublethal pH and the strain intrinsic acid tolerance: the lowest adaptation pH was 4.0 for strain LL56 and 5.7 for strain LL22, and the lowest pH values tolerated after adaptation were 3.0 and 4.0, respectively. Both complex and minimal medium allowed the development of the adaptive acid response, although in complex medium this response was more effective. Three low molecular weight polypeptides (LMWPs) showed increased expression in strain LL56 during the adaptation to pH 4.0. However, the adaptive acid tolerance was only partially dependent on de novo protein synthesis, and constitutive systems may play a significant role on the acid tolerance of Mesorhizobium huakuii strain LL56. 相似文献
953.
D Oppong V M King X Zhou J A Bowen 《Journal of industrial microbiology & biotechnology》2000,25(2):74-80
A study of 25 paper mill slime deposits and one additive revealed nine pink-pigmented bacterial isolates, eight of which were
different from pink-pigmented bacteria identified in the paper industry in the middle 1900s. The pink-pigmented bacteria described
previously in pulp and paper included Micrococcus agilis, Bacillus subtilis, Serratia sp. and Alcaligenes viscosus. With the exception of one isolate, Micrococcus sp., these isolates possessed many cultural, biochemical and chemical properties which were different from the ones previously
reported for paper mills. Eight of these bacteria were Gram-negative rods or filamentous, aerobic and positive for catalase
production. Two isolates were methylotrophic, oxidizing methanol and identified as Methylobacterium zatmanii. Cellular fatty acid analysis and other characteristics showed one isolate to be Roseomonas sp. Using 16S rRNA gene sequencing, one isolate which was a Gram-negative rod was identified as Deionococcus grandis. Four bacteria had cells that were long or filamentous and these were isolated from mills with pink slime problems. The identity
of one of the filamentous bacteria was determined by 16S rRNA gene sequencing to be close to Flectobacillus sp. strain MWH38. Most of the isolates were susceptible to 11 industrial biocides. Journal of Industrial Microbiology & Biotechnology (2000) 25, 74–80.
Received 28 January 2000/ Accepted in revised form 09 June 2000 相似文献
954.
H-J Son K-K Kim H-S Kim Y-K Kim S-J Lee 《Journal of industrial microbiology & biotechnology》2000,24(1):36-40
Pseudomonas sp EL-2 was cultivated to produce poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] from a structurally unrelated
carbon source, glucose, by a fed-batch culture technique. Variation of the carbon to nitrogen (C/N) ratio of the medium produced
optimal P(3HB-co-3HV) production at a C/N ratio of 95. Production of P(3HB-co-3HV) was favored by a dissolved oxygen tension
of 40%. A maximum biomass concentration of 38 g L−1 containing 53% P(3HB-co-3HV) was achieved after 45 h of cultivation. This corresponds to a volumetric productivity of 0.84 g
L−1 h−1. The copolymer contained 7.5 mol% 3-hydroxyvalerate. Journal of Industrial Microbiology & Biotechnology (2000) 24, 36–40.
Received 28 January 1999/ Accepted in revised form 11 September 1999 相似文献
955.
利用含亚麻子油的斜面培养基连续传代和逐渐降低培养温度,诱导筛选的方法,从大量丝状真菌中选育到一株产二十碳五烯酸(all-cis-5、8、11、14、17-eicosopnthenoicacid)较高的被孢霉菌(Motierellasp.)SM481。研究得到最适培养基及最适培养条件。在最适培养及产二十碳五烯酸条件下,细胞干重和二十碳五烯酸产量分别为28.8g/L和0.127g/L。 相似文献
956.
SHI Ding-Ji YE Xin ZHONG Hui CAI Yi-Ying SHAO Ning PENG Guo-Hong DONG Xiao-Jun WANG Chun-Mei OUYANG Ye-Xin LI Zhen-Jia 《植物学报(英文版)》2001,43(1):46-50
The effects of N (NaNO3) and C (NaAc) source in medium on the expression of tumor necrosis factor-α (TNF-α) gene in transgenic Anabaena sp. PCC 7120 were compared. The data showed that N source stabilized the expression of foreign protein and C source altered the synthesis of cell walls. Comparing several methods for breaking the cells, supersonic was able to extract TNF-α better than others. For purification of TNF-α, transgenic Anabaena cells were broken, the extracts were precipitated with ammonia sulfate, and the impure TNF-α was eluted from DEAE ion exchange chromatography. Electrophoresis (PAGE-SDS) showed a single band at 17 kD position. 相似文献
957.
湿地松粉蚧是于1988年传入我国广东省的一种重要林业外来入侵害虫。现在该害虫在我国的分布面积为35.52万公顷,严重影响着我国南方松林的生长健康。该害虫在其原产地美国南方并不造成大的危害,也不是一种主要害虫。只有当大量应用杀虫剂防治其它害虫时,由于杀死了其天敌,湿地松粉蚧种群才会明显增长。为控制这一外来入侵害虫,中美两国于1995年开展了从美国引进天敌防治广东省湿地松粉蚧的林业合作项目。本文报道了1996~1997年间在美国南方三个种子园使用杀虫剂防治球果种实害虫时,杀虫剂对湿地松粉蚧种群及其两种主要天敌有明显的影响,这也间接地说明了寄生性天敌对湿地松粉蚧在自然条件下的控制作用。相关分析显示湿地松粉蚧种群数量与其天敌是密切相关的,但杀虫剂可以打破这种平衡。这一方面说明从美国引进天敌防治湿地松粉蚧是可行的,另一方面也显示在美国采集湿地松粉蚧天敌应在使用过杀虫剂后的林分中。 相似文献
958.
从药用植物红豆杉(Taxus chinensis (Pilg.) Rehd.)的内生真菌--粘帚霉属真菌(Gliocladium sp., 简称F菌)菌丝体中分离到3个化合物, 根据光谱方法确定了它们的结构.其中,(20S,22S)-4a-同-22-羟基-4-氧杂麦角甾-7, 24 (28)-二烯-3-酮为新化合物,化合物4, 8, 12, 16-四甲基-1, 5, 9, 13-四氧杂环十六烷-2, 6, 10, 14-四酮为首次从该属真菌中分离到, 6,9-环氧麦角甾-7,22-二烯-3-羟基为首次从F菌中分离到. 相似文献
959.
960.
Micropropagation of three berry fruit species using nodal segments from field-grown plants 总被引:2,自引:0,他引:2
Plant micropropagation of blueberry (Vaccinium corymbosum L. cv. Berkeley), blackberry (Rubus sp. cv. Smoothstem) and raspberry (Rubus idaeus L. cv. Gradina) was carried out from nodal segments of adult field‐grown plants. Hardwood and softwood cuttings were studied as explant sources. The cultures successfully established were softwood from all three species, and hardwood only from blueberry. Shoot‐bud establishment from blueberry was achieved by culturing explants in WPM salts with MS vitamins for 15 days, and then 30 days in the same medium with 18 mM Zeatin. The best results of multiplication were obtained in the same medium with 25 mM 2iP. For blackberry, shoot‐bud establishment was achieved by culturing explants in MS medium for 15 days, and then in the same medium with 4 mM BA and 0.25 mM IBA. This medium was also the best for blackberry multiplication. Raspberry explants (cvs Gradina and Willamette) were cultured in MS medium for 15 days and then transferred to MS medium supplemented with 4 μm BA and 0.25 mM IBA. After 30 days of culture, only ‘Gradina’ explants survived, from which shoot‐bud establishment was obtained in a modified MS medium (Anderson's macronutrients except calcium, with Sequestrene as the iron source) with the same growth regulators. Multiplication was achieved by subculturing explants in the same medium either with 4 mM BA plus 0.25 mM IBA or with 8 mM BA plus 0.25 mM IBA. Shoots of at least 1 cm in length from all species were rooted ex vitro in a mixture of peat and Perlite (1:1, v/v) in a mist chamber, and 100% of rooting plants were acclimated. Bacterial, fungal and viral diseases were detected in stock plants, while tests carried out in both shoots and regenerated plants revealed the absence of any kind of disease. 相似文献