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181.
Ivanova EP Kurilenko VV Kurilenko AV Gorshkova NM Shubin FN Nicolau DV Chelomin VP 《Current microbiology》2002,44(5):357-362
The tolerance to Cd2+ and possible mechanisms of Cd2+ detoxification by 178 free-living bacteria isolated from sea water, associated with marine animals (a mussel Crenomytilus grayanus, a scallop Patinopecten yessoensis), and eelgrass Zostera marina collected in The Sea of Japan and The Sea of Okhotsk have been studied. The concentrations of 25 and 50 mg Cd2+/L were highly toxic and inhibited the growth from 54% to 78% of the total bacteria studied. The free-living bacteria isolated
from seawater samples (up to 50%) were tolerant to high concentrations of cadmium. Marine gamma-proteobacteria tolerated Cd2+ by the activation of different detoxifying mechanisms. The strain Halomonas sp. KMM 734 isolated from seawater prevented the uptake of Cd2+ into bacterial cells. The chromosomal cadmium resistance system of Pseudoalteromonas citrea KMM 461 and Marinobacter sp. KMM 181 was found to be similar to class III metallothioneins (also known as phytochelatins).
Received: 25 July 2001 / Accepted: 27 August 2001 相似文献
182.
Decreased prevalence of Orientia tsutsugamushi in trombiculid mites and wild rodents in the Primorye region, Far East Russia 总被引:1,自引:0,他引:1
Urakami H Tamura A Tarasevich IV Kadosaka T Shubin FN 《Microbiology and immunology》1999,43(10):975-978
The isolation of Orientia tsutsugamushi was attempted from 249 rodents and approximately 14,000 trombiculid mites captured in the Primorye region, Far East Russia in 1993 and 1994, where high infection rates were recorded in both rodents and mites in the 1960s. However, no rickettsia was isolated from the samples. Low antibody titers against O. tsutsugamushi were detected in 7.1% of the rodents. These results indicate that the prevalence of O. tsutsugamushi in the Primorye region has decreased considerably in the past 30 years. 相似文献
183.
The circular dichroism (CD) method was applied to study the molecular organization of P700, antenna chlorophyll and protein of photosystem 1 complexes (CP1), isolated from chloroplasts under mild treatment with Triton X-100. Analysis of CD spectra and protein: chlorophyll: P700 ratios for CP1 complexes that were different in their chlorophyll content indicate that CP1 preparations can be considered as a mixture of CP1-RC, containing P700 (10–20%), and CP1-LH without P700 (80–90%). Both types of complexes contain approximately 25 chlorophyll molecules, and the destruction of their spatial organization with detergents represents a cooperative transition. The rate of chlorophyll destruction in CP1-LH is much higher than that in CP1-RC. In both complexes a 65 kDa polypeptide predominates, whose secondary structure (typical for / proteins) is stable to Triton X-100 and does not depends on the chlorophyll content. Chlorophyll seems to be grouped in clusters (5–7 molecules) in the hydrophobic cores of 2–3 parallel / domains of the 65 kDa protein. Only one of the clusters in CP1-RC includes P700; on P700 photooxidation the change of its interaction with the nearest pigment environment results in a complicated shape of the light-induced CD spectra.Abbreviations PS1
photosystem 1
- CP1
pigment-protein complex of PS1
- Chl
chlorophyll a
- CP1-140
CP1 with ratio Ch1:P700 140
- RC
reaction center
- LH
light-harvesting pigment
- CP1-RC
CP1, containing P700
- CP1-LH
CP1 without P700 (containing LH)
- CD
circular dichroism
- SDS
sodium dodecyl sulfate
Dedicated to Prof. L.N.M. Duysens on the occasion of his retirement 相似文献
184.
本文记述1983年4月在山东省日照市刘东楼乡竹溪村附近山坡上采得的200余件石制品,从产状及形态来看,可以肯定为旧石器时代遗物,但究竟属于旧石器时代哪一阶段,还有待深入研究。 相似文献
185.
Maureen A Torok David M Gardiner Neil H Shubin Susan V Bryant 《Developmental biology》1998,200(2):225
Hoxgenes play a critical role in the development of the vertebrate axis and limbs, and previous studies have implicated them in the specification of positional identity, the control of growth, and the timing of differentiation. Axolotl limbs offer an opportunity to distinguish these alternatives because the sequence of skeletal differentiation is reversed along the anterior–posterior axis relative to that of other tetrapods. We report that during early limb development, expression patterns ofHoxDgenes in axolotls resemble those in amniotes and anuran amphibians. At later stages, the anterior boundary ofHoxd-11expression is conserved with respect to morphological landmarks, but there is no anterior–distal expansion of the posterior domain ofHoxd-11expression similar to that observed in mice and chicks. Since axolotls do not form an expanded paddle-like handplate prior to digit differentiation, we suggest that anterior expansion of expression in higher vertebrates is linked to the formation of the handplate, but is clearly not necessary for digit differentiation. We also show that the 5′HoxDgenes are reexpressed during limb regeneration. The change in the expression pattern ofHoxd-11during the course of regeneration is consistent with the hypothesis that the distal tip of the regenerate is specified first, followed by intercalation of intermediate levels of the pattern. BothHoxd-8andHoxd-10are expressed in non-regenerating wounds, butHoxd-11is specific for regeneration. It is also expressed in the posterior half of nerve-induced supernumerary outgrowths. 相似文献
186.
Interspecies genetic variability of Baikal seal was studied for 22 proteins encoded by 24 loci. Genetic variants have been detected in transferrin (TfA = 0.96; TfB = 0.04), postalbumin (PaA = 0.130; PaB = 0.870) and "slow" carboxylesterase (CrE-6A = 0.98; CrE-6B = 0.02). Low genetic variability is characteristic of species as well as of many other representatives of Pinnipedia order. 相似文献
187.
M M Delgado G Tikhonov E Meyke M Babushkin T Bespalova S Bondarchuk A Esengeldenova I Fedchenko Y Kalinkin A Knorre G Kosenkov V Kozsheechkin A Kuznetsov E Larin D Mirsaitov I Prokosheva Y Rozhkov A Rykov I V Seryodkin S Shubin R Sibgatullin N Sikkila E Sitnikova L Sultangareeva A Vasin L Yarushina J Kurhinen V Penteriani 《Frontiers in zoology》2018,15(1):41
Background
For brown bears (Ursus arctos), hibernation is a critical part of the annual life cycle because energy savings during hibernation can be crucial for overwintering, and females give birth to cubs at that time. For hibernation to be a useful strategy, timing is critical. However, environmental conditions vary greatly, which might have a negative effect on the functionality of the evolved biological time-keeping. Here, we used a long-term dataset (69 years) on brown bear denning phenology recorded in 12 Russian protected areas and quantified the phenological responses to variation in temperature and snow depth. Previous studies analyzing the relationship between climate and denning behavior did not consider that the brown bear response to variation in climatic factors might vary through a period preceding den entry and exit. We hypothesized that there is a seasonal sensitivity pattern of bear denning phenology in response to variation in climatic conditions, such that the effect of climatic variability will be pronounced only when it occurs close to den exit and entry dates.Results
We found that brown bears are most sensitive to climatic variations around the observed first den exit and last entry dates, such that an increase/decrease in temperature in the periods closer to the first den exit and last entry dates have a greater influence on the denning dates than in other periods.Conclusions
Our study shows that climatic factors are modulating brown bear hibernation phenology and provide a further structuring of this modulation. The sensitivity of brown bears to changes in climatic factors during hibernation might affect their ability to cope with global climate change. Therefore, understanding these processes will be essential for informed management of biodiversity in a changing world.188.
189.
Ying Xu Hu Tian Jialin Cheng Shubin Liang Teng Li Ju Liu 《Cell biology international》2019,43(11):1286-1295
Telocytes had been identified as a peculiar stromal cell type implicated in tissue homeostasis and the development and pathophysiology of diseases. Telocyte existed in most organs and tissues in humans and animals. However, few studies have examined telocytes in ApoE gene deficient mice. In our studies, we verified the existence, the morphology and immunohistochemical characteristics of telocytes in critical organs of the ApoE?/? mice. Male adult ApoE?/? mice were selected as an experimental model. Immunohistochemical bio‐markers, such as CD34, CD117, CD28, Vimentin and PDGFR‐α were utilized to determine the distribution and morphology of telocytes in the heart, liver and kidney. Telocyte expressed positively for CD34 and CD117, and partial telocyte and telopode expressed positively for PDGFR‐α in heart and liver, but negatively in kidney. Double immunofluorescence assays for CD28/Vimentin, CD34/CD117 and CD34/PDGFR‐α were used to demonstrate the biochemistry speciality of telocytes, respectively. The evidence of telocytes in the ApoE‐/‐ mice is the first step of our sturdy, which aims to demonstrate changes in telocytes in atherosclerosis in this animal model. 相似文献
190.
东方白鹳(Ciconia boyciana)主要在俄罗斯远东和中国东北繁殖, 在中国主要有两个越冬群体(长江越冬群体, 迁徙距离约2,600 km; 渤海湾越冬群体, 迁徙距离约1,500 km)。本文基于2016-2018年的卫星追踪数据(N = 14), 分析了渤海湾越冬群体幼鸟春季和秋季的迁徙策略和利用风的方式, 总结了850 mb压力下风速和风向对日迁徙飞行速度的影响。该群体春秋两季迁徙距离相似, 但春季的顺风条件(2.2 ± 6.3 m/s)显著优于秋季的逆风条件(-2.4 ± 4.1 m/s, P < 0.05), 这使得春季迁徙飞行速度(280.4 ± 62.0 km/d)显著快于秋季(185.5 ± 72.0 km/d, P < 0.05), 春季迁徙飞行时间(5.9 ± 2.5 d)显著短于秋季(10.3 ± 6.5 d, P < 0.05); 同时, 春季停歇时间(5.4 ± 9.7 d)短于秋季(17.8 ± 18.2 d, P = 0.05)。基于以上原因, 东方白鹳春季迁徙持续时间(11.2 ± 8.7 d)显著短于秋季(28.0 ± 21.2 d, P < 0.05)。渤海湾越冬群体幼鸟迁徙时, 春季利用顺风更快到达度夏地, 秋季逆风迁徙, 迁徙飞行速度慢, 迁徙飞行时间和停歇时间长。因此, 东方白鹳迁徙时虽然主要利用上升热气流翱翔, 但顺风也是其成功迁徙的有利因素。 相似文献