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1.
3种褐藻色素-蛋白复合物的分离及光谱特性   总被引:1,自引:0,他引:1  
以非离子去污剂DMG增溶3种褐藻的类囊体膜 ,经SDS PAGE分离色素 蛋白质复合物 ,并测定其光谱特性及表观分子量。结果表明 ,3种褐藻的电泳分离结果完全相同 ,都分离到6条含色素的蛋白质复合物。从不同褐藻类囊体膜上得到的同一种复合物的吸收光谱和荧光发射光谱特性一致 ,3种褐藻的PSI复合物都有位于715nm处的长波荧光发射峰。电泳方法测得3种褐藻同一种色素 蛋白质复合物的表观分子量相近。  相似文献   

2.
以非离子去污剂DMG增溶3种褐藻的类囊体膜,经SDS-PAGE分离色素-蛋白质复合物,并测定其光谱特性及表现分子量。结果表明,3种褐藻的电泳分离结果完全相同,都分离到6条含色素的蛋白质复合物。从不同褐藻类囊体膜上得到的同一种复合物的吸收光谱和荧光发射光谱特性一致,3种褐藻的PSI复合物都有位于715nm处的长波荧光发射峰。电泳方法测得3种褐藻同一种以素-蛋白质复合物的表观分子量相近。  相似文献   

3.
刘洪艳 《海洋通报》2007,26(6):37-41
以褐藻裙带菜(Undaria pinnatifida)和绿藻石莼(Ulva pertusa)为实验材料,利用SDS,Dig,Triton X-100三种去污剂,分别与叶绿素按不同比例增溶类囊体膜,采用蔗糖密度梯度超速离心的方法分离色素蛋白复合物,蔗糖密度梯度为60%,50%,40%,30%,20%,15%和10%。实验结果表明:当SDS与叶绿素质量比为20∶1时,能够从裙带菜类囊体膜中分离得到5条含蛋白质复合物带。对于石莼类囊体膜的增溶,当SDS与叶绿素的质量比为10∶1,Triton与叶绿素质量为20∶1时,同样能够分离得到5条含蛋白质复合物带。褐藻和绿藻色素蛋白复合物对去污剂的敏感程度有很大差别。  相似文献   

4.
以褐藻裙带菜(Undaria pinnatifida)为实验材料,采用蔗糖密度梯度超速离心的方法纯化类囊体膜;以去污剂sDs为增溶剂(SDS:Chl=20:1,4℃增溶20min),再用蔗糖密度为60%、50%、40%、30%、20%、15%和10%的梯度离心法,从裙带菜中成功地分离出5条含色素的蛋白质复合物带。离心结果显示在离心管顶部没有任何颜色,表明经过SDS增溶没有产生游离色素,纯化的类囊体膜和5条色素条带进行吸收光谱分析,显示了属于叶绿素n(Chl-a)的吸收峰:418、436和667到672nm。叶绿素c(Chl-c)的吸收峰:615和620nm。荧光发射最高峰位于682到690nm的区域。荧光激发光谱显示有Chl-a和Chl-c的激发峰,40%层带所含有的色素复合物只有属于Chl.n的吸收峰。分析结果表明:10%、15%层带所含有的色素复合物是褐藻的捕光色素复合物;20%、30%层带所含有的色素复合物是浅绿色的PSⅡ复合体(仍然含有捕光色素),40%层带所含有的色素复合物是深绿色PSⅠ复合体,50%层带所含有的色素复合物是没有被增溶的类囊体膜。  相似文献   

5.
以褐藻裙带菜(Undaria pinnatifida)为实验材料,建立一条能够分离出有光活性PSⅡ复合物的技术路线。采用蔗糖密度梯度超速离心的方法,以去污剂SDS为增溶剂(SDS∶Chl=20∶1,4℃增溶20 min),蔗糖质量分数梯度为10%,15%,20%,30%,40%,50%和60%,从裙带菜中成功地分离出5条含色素的蛋白质复合物带。通过对裙带菜各色素蛋白复合物的光谱分析并进行了DCIP的光还原测定和化学法的氧化还原差示光谱测定,确定了20%和30%层带的复合物为PSⅡ复合物,具有DCIP的光还原活性。利用离子交换层析的方法并通过光谱鉴定分析得到了比较纯化的PSⅡ中心复合物。  相似文献   

6.
本文以蓝绿温和胶电泳为工具,首次在国内用于条斑紫菜类囊体膜色素蛋白质复合物的研究。结果显示:(1)利用非离子型去污剂十二烷基麦芽糖苷(DM)增溶条斑紫菜类囊体膜,DM/Chla(w/w)15:1产生的效果较好,在BN-PAGE胶中可以分离到较多较清晰的条带。(2)选取蔗糖密度层50%条带制备得到的类囊体膜样品进行第一向BN-PAGE和第二向SDS-Urea-PAGE电泳实验。第一向电泳分离出4个蛋白复合物,对第二向电泳胶上的15个蛋白点切取做质谱鉴定,检测到PSⅡ 47KDa,PSⅡ 44KDa,cytochrome f ,PSⅡ D2,PSⅡ D1等蛋白。本实验证实了温和胶电泳与SDS电泳结合对于条斑紫菜这种原始红藻的类囊体膜研究方面应用的可行性。  相似文献   

7.
以蓝绿温和胶电泳为工具,首次在国内用于条斑紫菜(Porphyra yezoensis)类囊体膜色素蛋白质复合物的研究。结果显示:(1)利用非离子型去污剂十二烷基麦芽糖苷(DM)增溶条斑紫菜类囊体膜,DM/Chla(w/w)15︰1产生的效果较好,在BN-PAGE胶中可以分离到较多较清晰的条带。(2)选取蔗糖密度层50%条带制备得到的类囊体膜样品进行第一向BN-PAGE和第二向SDS-Urea-PAGE电泳实验。第一向电泳分离出4个蛋白复合物,对第二向电泳胶上的15个蛋白点切取做质谱鉴定,检测到PSⅡ47ku,PSⅡ44ku,cytochrome f,PSⅡD2,PSⅡD1等蛋白。本实验证实了温和胶电泳与SDS电泳结合对于条斑紫菜这种原始红藻的类囊体膜研究方面应用的可行性。  相似文献   

8.
采用蔗糖密度梯度离心法分离纯化大叶藻类囊体膜 ,经 1 0 %SDS增溶后 ,用蔗糖密度梯度超速离心分离其色素蛋白质复合物。经稳态光谱分析、DCIP光还原活性测定及P680 、P70 0 差示光谱检测结果表明 ,2 0 %蔗糖层的CP3和 40 %蔗糖层 (上 )的CP4为PSⅡ复合物 ,具有光化学活性 ;40 %蔗糖层 (下 )的CP5为PSⅠ复合物 ,其P70 0 特征吸收峰位于 695nm处。CP3和CP4的DCIP光还原活性 :CP3为 34.2 7微电子当量 /(mgchl·h) ,CP4为 7.2 9微电子当量 /(mgchl·h)。  相似文献   

9.
采用温和的聚丙烯酰胺凝胶电泳(PAGE)法,从管藻目录藻刺松藻中分离到不同解离程度的光系统I(PSI)复合物,以及核心复合物CCI、捕光复合物LHCI和LHCI的亚组分,并就其多肽组成及相互关系做了研究。纯化的CCI复合物只含有66和56kDa多肽,荧光发射主峰在714-715nm;LHCI的77K荧光峰在683-684nm,没有高等植物730nm特征荧光,含有PSI复合物中的全部4种24.7-27.5kDa多肽。将中心复合物CPI再电泳,得到了只含24.5和27.2kDa多肽的LHCI亚组分。从而证实刺松藻LHCI也可分裂为含有光合色素的两个部分,它们与CCI结合的紧密程度不同。  相似文献   

10.
黑绸Sparusmacrocephalus(Basilewsky)视网膜中存在视杆、单锥和孪生双锥三种光感受细胞,视杆与视锥的比例较大,为67:1。每一双极细胞接受约5—8个视杆的输入,每一神经节细胞接受约17—25个双极细胞输入,表明神经节细胞有较大的感受野。视网膜细胞这种形态组合有利于提高视网膜对光的敏感性,与黑鲷生存的浅海底层弱光环境相适应。黑鲷的视杆色素经测定为视紫红质VP4851(吸收光谱峰值为485nm),其吸收光谱与黑鲷栖息水层中日光能量分布相对应,也与该水层中的生物光场相适应。黑鲷暗视光谱敏感曲线峰值与视紫红质吸收光谱曲线相一致,均在485nm处。此外,黑鲷光谱敏感曲线存在普氏位移,表明黑鲷具有辩色力。  相似文献   

11.
近年来, 渤海夏季低氧现象频发, 引起了人们的广泛关注。然而对该海域低氧形成的机制还未得到充分认识。研究基于在秦皇岛外海的现场观测, 分析了海水中颗粒物吸收光谱特征及其与不同粒径浮游植物叶绿素a (chl a)组成、环境因子的关系, 评估了夏季底层水体脱氧过程中有机物来源与特征。结果显示,夏季秦皇岛外海微型浮游植物chl a占总量的80%。表层水体中, 总颗粒物吸收光谱[ap(l)]特征由浮游植物色素吸收光谱[aph(l)]主导, 在中、底层水体中则由碎屑颗粒物吸收光谱[ad(l)]主导。垂向上, ap(440)和ad(440)均表现为表层<中层<底层。结果还表明, 浮游植物粒径主导秦皇岛外海chl a的光吸收效率, 即a*ph(440)。基于三粒级chl a含量, 可利用多元回归预测aph(440)。碎屑颗粒物的吸收光谱同样受浮游植物群落、有机质相对含量等的影响。研究结果表明初级生产产生的微型颗粒有机物是底层水体脱氧的主要底物。  相似文献   

12.
《Marine Chemistry》2002,77(1):23-41
Chromophoric dissolved organic matter (CDOM) is the light absorbing fraction of dissolved organic carbon (DOC). The optical properties of CDOM potentially permit remote sensing of DOC and CDOM, and correction for CDOM absorption is essential for remote sensing of chlorophyll a (chl a) in coastal and estuarine waters. To provide data for this purpose, we report the distributions of CDOM, DOC, and chl a from seven cruises in Chesapeake Bay in 1994–1997. We observed non-conservative distributions of chl a and DOC in half of the cruises, indicating net accumulations within the estuary; however, there were no net accumulations or losses of CDOM, measured as absorption at 355 nm or as fluorescence. Freshwater end member CDOM absorption varied from 2.2 to 4.1 m−1. Coastal end member CDOM absorption was considerably lower, ranging over 0.4–1.1 m−1. The fluorescence/absorption ratio was similar to those reported elsewhere for estuarine and coastal waters; however, in the lower salinity/high CDOM region of the Bay, the relationship was not constant, suggestive of the mixing of two or more CDOM sources. Chl a was not correlated with the absorption for most of the cruises nor for the data set as a whole; however, CDOM and DOC were significantly correlated, with two groups evident in the data. The first group had high CDOM concentrations per unit DOC and corresponded to the conservative DOC values observed in the transects. The second group had lower CDOM concentrations per unit DOC and corresponded to the non-conservative DOC values associated with net DOC accumulation near the chl a maximum on the salinity gradient. This indicates the production of non-chromophoric DOC in the region of the chl a maximum of Chesapeake Bay. In terms of remote sensing, these data show that (1) the retrieval of the absorption coefficient of CDOM from fluorescence measurements in the Bay must consider the variability of the fluorescence/absorption relationship, and (2) estimates of DOC acquired from CDOM absorption will underestimate DOC in regions with recent, net accumulations of DOC.  相似文献   

13.
Phytoplankton dynamics during the northeast monsoon was investigated in the Sulu Sea from algal pigment analysis. We visited the Sulu Sea in February 2000, a mid period of the northeast monsoon, and in November and December 2002, the beginning of the northeast monsoon. SeaWiFS images showed generally low concentrations of surface chlorophyll a (Chl a) during the southwest monsoon and higher concentrations with several peaks during the northeast monsoon. In the beginning of the northeast monsoon, subsurface chlorophyll maxima (SCM) occurred, where vertical variation in class-specific composition as estimated from pigment signatures was prominent. Prochlorococcus, cyanobacteria, prymnesiophytes and crysophytes were important groups above the SCM, and the contribution of cyanobacteria to Chl a became much lower at and below the SCM. Contributions of chlorophytes and prasinophytes to Chl a generally showed maxima near the SCM. This distribution was accompanied by vertical changes in the concentration of photoprotective pigments relative to photosynthetic accessory pigments. During the mid northeast monsoon, the upward supply of nutrients was probably enhanced at some stations due to vertical mixing, and as a consequence diatoms dominated in the upper 100 m water column of these stations, and other eukaryotic flagellates including prymnesiophytes, chrysophytes and cryptophytes were secondary major components of the community. The elevation of Chl a concentration and changes in phytoplankton community during the northeast monsoon likely influence the variation in biological production at higher trophic levels in the Sulu Sea.  相似文献   

14.
We report on the ability for luxury Fe uptake and the potential for growth utilizing intracellular Fe pools for 4 coastal centric diatom isolates and in situ phytoplankton assemblages, mainly composed of diatoms. Iron uptake of the diatom isolates and natural phytoplankton assemblages in the Oyashio region during spring blooms were prevented by adding hydroxamate siderophore desferrioxamine B (DFB). After the addition of DFB, intracellular Fe in the diatom isolates supported 2.4–4.2 cell divisions with 1.2–2.6 Chl a doublings. The intracellular Fe was primarily used for cell generation rather than Chl a production, leading to a reduction in the Chl a cell quota in the Fe-starved cells with time. The metabolic properties of the Fe-starved cells with their cell morphologies were different among species or genera. An on-deck incubation experiment also exhibited 1.9 cell divisions and 0.81 Chl a doublings of phytoplankton after the addition of DFB, also indicating the preference of cell generation over Chl a production. A decrease in the level of cellular Chl a, a main light-harvesting pigment in Fe-starved diatoms, may become a superior survival strategy to protect the cells from high irradiance that can cause photo-oxidative damages through photosynthesis. Such relatively low-Fe with high-light conditions could often occur in surface waters of the Oyashio region from spring to summer.  相似文献   

15.
Remote sensing reflectance [R rs(λ)] and absorption coefficients of red tides were measured in Isahaya Bay, southwestern Japan, to investigate differences in the optical properties of red tide and non-red tide waters. We defined colored areas of the sea surface, visualized from shipboard, as “red tides”. Peaks of the R rs(λ) spectra of non-red tide waters were at 565 nm, while those of red tides shifted to longer wavelengths (589 nm). The spectral shape of R rs(λ) was close to that of the reciprocal of the total absorption coefficient [1/a(λ)], implying that the R rs(λ) peak is determined by absorption. Absorption coefficients of phytoplankton [a ph(λ)], non-pigment particles and colored dissolved organic matter increased with increasing chlorophyll a concentration (Chl a), and those coefficients were correlated with Chl a for both red tide and non-red tide waters. Using these relationships between absorption coefficients and Chl a, variation in the spectrum of 1/a(λ) as a function of Chl a was calculated. The peak of 1/a(λ) shifted to longer wavelengths with increasing Chl a. Furthermore, the relative contribution of a ph(λ) to the total absorption in red tide water was significantly higher than in non-red tide water in the wavelength range 550–600 nm, including the peak. Our results show that the variation of a ph(λ) with Chl a dominates the behavior of the R rs(λ) peak, and utilization of R rs(λ) peaks at 589 and 565 nm may be useful to discriminate between red tide and non-red tide waters by remote sensing.  相似文献   

16.
In order to determine the phytoplankton community composition, the modification and optimizing of the CHEMical TAXonomy (CHEMTAX) running was carried out through samples grouping, successive run and ev...  相似文献   

17.
依据2008年春季(5月)、夏季(8月)、秋季(11月)和2009年冬季(2月)的现场调查结果,分析了东海区叶绿素a、初级生产力的平面分布、垂直分布和季节变化的特征,并探讨了其影响因素。结果表明,四个航次叶绿素a浓度分别为1.33、0.93、1.61和0.65 mg/m3,秋季春季夏季冬季。春季、夏季和秋季最大值均出现在0—10m水层,冬季最大值出现在底层。叶绿素a浓度远海年季变化较小,近岸区和垂直分布年季变化较大。四个航次初级生产力平均为375.03、414.37、245.45和102.60 mg/(m3 h),夏季秋季春季冬季。叶绿素a浓度和初级生产力水平均高于历史同期值。鱼外渔场的年平均初级生产力最大,海州湾渔场最小。通过分析叶绿素a和环境因子的相关性表明,叶绿素a与浮游植物显著正相关;春季和秋季的低温以及春季和夏季的低盐比较适合浮游植物的生长;活性磷酸盐可能是限制春季和秋季叶绿素a的重要因素。  相似文献   

18.
Upwelling occurs on the coast of Java between June and October, forced by local alongshore winds associated with the southeasterly monsoon. This causes variations in phytoplankton community composition in the upwelling zone compared with the surrounding offshore area. Based on pigments analysis with subsequent calculations of group contributions to total chlorophyll a(Chl a) using CHEMTAX, we studied the distribution and composition of phytoplankton assemblages in the subsurface chlorophyll maximum along the south coast of Java and the influence of upwelling. Nineteen phytoplankton pigments were identified using high-performance liquid chromatography, and CHEMTAX analysis associated these to ten major phytoplankton groups. The phytoplankton community in the coastal area influenced by upwelling was characterized by high Chl a and fucoxanthin concentrations, indicating the dominance of diatoms. In contrast, in the offshore area, the Chl a and fucoxanthin concentrations declined to very low levels and the community was dominated by haptophytes represented by 19′-Hexanoyloxyfucoxanthin. Accordingly, microphytoplankton was found to be the major size class in the coastal area influenced by upwelling, while nanophytoplankton was most abundant in the offshore area. Low concentrations of other accessory pigments indicated less contribution from dinoflagellates,prasinophytes, chlorophytes and cryptophytes. Photo-pigment indices revealed that photosynthetic carotenoids(PSCs) were the largest component of the pigment pool, exceeding the proportion of Chl a, with the average PSCTP up to 0.62. These distribution trends can mainly be explained by phytoplankton adaption strategies to upwelling and subsurface conditions by changing species composition and adjusting the pigment pool.  相似文献   

19.
The distribution of chlorophyll a(Chl a) and its relationships with physical and chemical parameters in different regions of the Bering Sea were discussed in July 2010. The results showed the seawater column Chl a concentrations were 13.41–553.89 mg/m2 and the average value was 118.15 mg/m2 in the study areas. The horizontal distribution of Chl a varied remarkably from basin to shelf in the Bering Sea. The regional order of Chl a concentrations from low to high was basin, slope, outer shelf, inner shelf, and middle shelf. The vertical distribution of Chl a was grouped mainly from single-peak type in basin, slope, outer shelf, and middle shelf, where the deep Chl a maxima(DCM) layer was observed at 25–50 m, 30–35 m, 36–44 m, and 37–47 m, respectively. The vertical distribution of Chl a mainly had three basic patterns: standard single-peak type, surface maximum type, and bottom maximum type in the inner shelf. The analysis also showed that the transportation of ocean currents may control the distribution of Chl a, and the effects were not simple in the basin of the Bering Sea. There was a positive correlation between Chl a and temperature, but no significant correlation between Chl a and nutrients. The Bering Sea slope was an area deeply influenced by slope current. Silicate was the factor that controlled the distribution of Chl a within parts of the water in the slope. Light intensity was an important environmental factor in controlling seawater column Chl a in the shelf, where Chl a was limited by nitrate rather than phosphate within the upper water. Meanwhile, there was a positive relationship between Chl a and salinity. Algal blooms broke out at Sta. B6 of the southwestern St. Lawrence Island and Stas F6 and F11 in the middle of the Bering Strait.  相似文献   

20.
Phytoplankton absorption and pigment characteristics of a red tide were investigated in coastal waters of the southern Benguela. Diagnostic indices indicated that dinoflagellates were the dominant phytoplankton group, with diatoms and small flagellates being of secondary importance. Very high biomass was observed close to the coast where chlorophyll a concentrations of up to 117 mg m–3 were measured. Both measured (a ph) and reconstructed pigment absorption (a pig) displayed an increasing trend with chlorophyll a, while the package effect index (Q* a) decreased, indicating increased packaging with an increase in biomass. Proportioning of the total pigment absorption between 400 and 700 nm revealed that chlorophyll a accounted for 39–65% of the absorption, while photosynthetic carotenoids (15–30%) and chlorophyll cs (15–30%) were also prominent in absorbing light for photosynthesis.  相似文献   

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