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1.
M. Y. Shukor M. F. Rahman Z. Suhaili N. A. Shamaan M. A. Syed 《World journal of microbiology & biotechnology》2009,25(7):1225-1234
A bacterium that was able to tolerate and reduce as high as 50 mM of sodium molybdate to molybdenum blue has been isolated
from a metal recycling ground. The isolate was tentatively identified as Serratia sp. strain Dr.Y8 based on the carbon utilization profiles using Biolog GN plates and partial 16S rDNA molecular phylogeny.
ANOVA analysis showed that isolate Dr.Y8 produced significantly higher (P < 0.05) amount of Mo-blue with 3, 5.1 and 11.3 times more molybdenum blue than previously isolated molybdenum reducers such
as Serratia
marcescens strain Dr.Y6, E. coli K12 and E. cloacae strain 48, respectively. Its molybdate reduction characteristics were studied in this work. Electron donor sources such as
sucrose, mannitol, fructose, glucose and starch supported molybdate reduction. The optimum phosphate, pH and temperature that
supported molybdate reduction were 5 mM, pH 6.0 and 37°C, respectively. The molybdenum blue produced from cellular reduction
exhibited a unique absorption spectrum with a maximum peak at 865 nm and a shoulder at 700 nm. Metal ions such as chromium,
silver, copper and mercury resulted in approximately 61, 57, 80, and 69% inhibition of the molybdenum-reducing activity at
1 mM, respectively. The reduction characteristics of strain Dr.Y8 suggest that it would be useful in future molybdenum bioremediation. 相似文献
2.
Variation in the ribosomal internal transcribed spacers (ITS1 and ITS2) among eight taxa of the Mimulus guttatus species complex 总被引:1,自引:0,他引:1
The internal transcribed spacer region (ITS1 and ITS2) of the 18S-25S
nuclear ribosomal DNA sequence and the intervening 5.8S region were
sequenced from three individuals in each of eight taxa of the Mimulus
guttatus species complex. Three discrete variants, or "types," of ITS
sequences were found, among which 30%-40% of sites differed, compared with
1%-2% within types. Dot plots indicate that these types were not related by
conspicuous rearrangements or inversions. More than one ITS type was often
found in the same taxon, and two of three ITS types span species
boundaries, indicating their presence prior to speciation. These ITS
sequences showed essentially no positional homology with the nearest
sequenced relative, tomato. In contrast, the 5.8S region was relatively
unvaried, with 8 of 162 sites varied in the sample among all eight taxa.
The phylogeny inferred by the most common ITS sequence type, rooted by the
two other ITS types, agreed with isozymes in showing the distinctness of M.
nudatus, M. laciniatus, and M. tilingii from the other five taxa.
相似文献
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大中型食肉动物肇事事件导致人类与野生动物关系恶化,给生物多样性保护工作带来巨大的挑战。若尔盖湿地是我国三大湿地之一,湿地、草原分布广泛,生物多样性丰富,畜牧业发达,但近年来狼(Canis lupus)捕杀牲畜的肇事事件时有发生。为了解若尔盖野生狼肇事件的空间分布以及牧民对人-狼冲突管理的看法,本研究于2022年对若尔盖县13个乡镇83个行政村进行走访调查。结果表明:(1)多数受访者(66.0%)认为在过去5年内,若尔盖县野生狼数量有所增加;(2)狼肇事事件具有明显的空间分异性,最严重的是包座乡。包座乡临近山区,该区域牧场面积广阔、牧民饲养牲畜数量多等原因导致该镇发生狼肇事事件较多;(3)对于狼肇事,绝大多数牧民(85.0%)更希望采取经济补偿或者驱赶措施,只有少数牧民(9.4%)希望采取捕杀的措施;(4)影响牧民对狼肇事管理措施的偏好因子中,受教育程度、年龄、民族以及被杀牲畜数量有显著影响。建议加强狼种群监测管理,采取措施减少狼捕杀牲畜,优化补偿机制,缓解当地牧民与狼之间的矛盾。本研究为当前若尔盖县野生动物保护和管理决策提供了依据,对其他地区大型食肉动物与当地居民冲突管理具有借鉴意义。 相似文献
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Different values have resulted in conflicts between anglers and conservation lobbies in the management of trout in South Africa. Key to the conflict is the demarcation of boundaries to areas in which brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss currently occur, or are likely to establish following stocking for angling. To provide a longer-term perspective on these areas, we developed models to link salmonid biological thermal thresholds to elevation. These, when applied spatially using a digital elevation model with a probability of occurrence model, provided the basis for estimating potentially available thermal habitat for these two cold water species. Here, we acknowledge that other variables (stocking history; river connectivity) also play a role in understanding trout distributions. Using a simple scenario of an increase in mean daily water temperatures of 2 °C, we demonstrated that both brown and rainbow trout are likely to exhibit considerable range reductions in the future. Because it is possible that these range restrictions will result in an increasing desire to introduce trout into areas above their current distribution limits for the maintenance of angling opportunities, conservation managers should prioritise these areas, with management interventions seeking to understand what will help to limit introductions. 相似文献
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从茎花葱臭木种子中分离得到5个化合物,经理化与波谱分析鉴定为β-谷甾醇(1)、没食子酸乙酯(2)、胡萝卜苷(3)、1-O-β-D-吡喃葡萄糖基-(2S,3S,4R,8Z)-2-N-(2 ′-羟基二十四烷酰氨基)十八二氧鞘氨-8-烯(4)和2,3,2″,3″-四氢穗花杉双黄酮(5).这5个化合物均首次从该植物中分离得到.其中化合物5进行细胞毒活性测试,没有显示抑制活性. 相似文献
10.
甘薯愈伤组织中的淀粉酶 总被引:7,自引:0,他引:7
从甘薯愈伤组织和块根可溶性提取物中淀粉酶的非变性凝胶电泳和活性染色发现 ,愈伤组织和块根的淀粉酶完全不同。前者有 4种不同大小的淀粉酶 (2种α 淀粉酶和 2种 β 淀粉酶 ) ,而后者只有一种 (β 淀粉酶 ) ;其次 ,块根 β 淀粉酶对EDTA和 β 巯基乙醇都不敏感 ,而愈伤组织的淀粉酶对EDTA和 β 巯基乙醇都敏感。这些结果表明甘薯愈伤组织中不仅淀粉酶同工酶的数量多 ,而且包括α和 β两种类型。 相似文献