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Floating Escherichia coli by Expressing Cyanobacterial Gas Vesicle Genes

Journal of ocean University of China 2015年第1期14卷 84-88页

作者： WANG Tianhe KANG Li LI Jiaheng WU Wenjie ZHANG Peiran GONG Minghao LAI Weihong ZHANG Chunyan CHANG Lei PENG Yong YANG Zhongzhou LI Lian BAO Yingying XU Haowen ZHANG Xiaohua SUI Zhenghong YANG Guanpin WANG Xianghong College of Marine Life Science Ocean University of China school of Medicine and Pharmacy Ocean University of China College of Fisheries Ocean University of China College of Information Science and Engineering Ocean University of China school of Mathematical sciences Ocean University of China Experimental Teaching Center of Marine Life sciences Ocean University of China

Gas vesicles are hollow, air-filled polyprotein structures that provide the buoyancy to cells. They are found in a variety of prokaryotes. In this study, we isolated a partial gas vesicle protein gene cluster containing gvpA and gvpC20ψ from Planktothrix rubescens, and inserted it into an expression vector and expressed it in E. coli. The gas vesicle was developed in bacterial cells, which made bacterial cells to float on medium surface. We also amplified gvpA and gvpC20ψ separately and synthesized an artificial operon by fusing these two genes with the standardized gene expression controlling elements of E. coli. The artificial operon was expressed in E. coli, forming gas vesicles and floating bacteria cells. Our findings verified that the whole set of genes and the overall structure of gas vesicle gene cluster are not necessary for developing gas vesicles in bacteria cells. Two genes, gvpA and gvpC20ψ, of the gas vesicle gene cluster are sufficient for synthesizing an artificial operon that can develop gas vesicles in bacteria cells. Our findings provided a wide range of applications including easing the harvest of cultured microalgae and bacteria, as well as enriching and remediating aquatic pollutants by constructing gas vesicles in their ceils.

关键词： gas vesicle gene cluster gas vesicle gene buoyancy

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Quantifying climate conditions for the formation of coals and evaporites

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National Science Review 2023年第6期10卷 143-150页

作者： Xiujuan Bao Yongyun Hu Christopher R.Scotese Xiang Li Jiaqi Guo Jiawenjing Lan Qifan Lin Shuai Yuan Mengyu Wei Zhibo Li Kai Man Zihan Yin Jing Han Jian Zhang Qiang Wei Yonggang Liu Jun Yang Ji Nie Laboratory for Climate and ocean-Atmosphere Studies Department of Atmospheric and Oceanic Sciences School of Physics Peking University Department of Earth and Planetary sciences Northwestern University

Coals and evaporites are commonly used as qualitative indicators of wet and dry environments in deep-time climate studies,***,we combine geological records with climate simulations to establish quantitative relationships of coals and evaporites with temperature and precipitation over the *** show that coal records were associated with a median temperature of 25℃ and precipitation of1300 mm yr-1before 250 ***,coal records appeared with temperatures between 0℃ and 21℃and precipitation of 900 mm *** records were associated with a median temperature of 27℃and precipitation of 800 mm *** most remarkable result is that net precipitation associated with coal and evaporite records remained constant across *** results here have important implications for quantifying climate conditions for other lithologic indicators of climate and for predicting exogenetic ore deposits.

关键词： deep-time climate evolution coals evaporites temperature precipitation

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Sources and transformations of nitrite in the Amundsen Sea in summer 2019 and 2020 as revealed by nitrogen and oxygen isotopes

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Acta oceanologica Sinica 2023年第4期42卷 16-24页

作者： Yangjun Chen Jinxu Chen Yi Wang You Jiang Minfang Zheng Yusheng Qiu Min Chen College of ocean and Earth sciences Xiamen UniversityXiamen 361102China school of Marine Science and Fisheries Jiangsu Ocean UniversityLianyungang 222005China

In this study,the nitrogen and oxygen isotope compositions of nitrite in the upper 150 m water column of the Amundsen Sea in the summer of 2019 and 2020 were measured to reveal the distribution and transformation of nitrite in the euphotic zone of the Southern *** found that primary nitrite maxima(PNMs)are widely present in the Amundsen Sea,where the depth of occurrence deepens from east to west and nitrite concentrations *** from dual isotopes suggests that the formation of PNMs in all regions of the Amundsen Sea is dominated by ammonia *** importantly,the nitrogen and oxygen isotope compositions of nitrite in the Amundsen Sea mixed layer are abnormal,and their depth profiles are mirror *** anomalies exhibit spatial variations,with central surface water having the lowest nitrogen isotope composition(−89.9‰±0.2‰)and western surface water having the highest oxygen isotope composition(63.3‰±0.3‰).Isotopic exchange reaction between nitrate and nitrite is responsible for these isotope anomalies,as both nitrogen and oxygen isotopes have large isotopic fractionation and opposite enrichment *** proves that isotopic exchange reaction operates extensively in different regions of the Amundsen *** study highlights the unique role of dual isotopes of nitrite in deepening the understanding of nitrogen *** studies on ammonia oxidation and isotopic exchange between nitrate and nitrite are warranted in the future to understand their roles in the nitrogen cycle in the Southern ocean.

关键词： nitrogen isotope oxygen isotope nitrite Amundsen Sea

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Discussion of skill improvement in marine ecosystem dynamic models based on parameter optimization and skill assessment

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Chinese Journal of oceanology and Limnology 2016年第4期34卷 683-696页

作者：沈程程石洪华刘永志李芬丁德文 College of Environmental Science and Engineering Ocean University of China The First Institute of oceanography State Oceanic Administration school of Mathematical sciences Ocean University of China

Marine ecosystem dynamic models(MEDMs) are important tools for the simulation and prediction of marine ecosystems. This article summarizes the methods and strategies used for the improvement and assessment of MEDM skill, and it attempts to establish a technical framework to inspire further ideas concerning MEDM skill improvement. The skill of MEDMs can be improved by parameter optimization(PO), which is an important step in model calibration. An effi cient approach to solve the problem of PO constrained by MEDMs is the global treatment of both sensitivity analysis and PO. Model validation is an essential step following PO, which validates the effi ciency of model calibration by analyzing and estimating the goodness-of-fi t of the optimized model. Additionally, by focusing on the degree of impact of various factors on model skill, model uncertainty analysis can supply model users with a quantitative assessment of model confi dence. Research on MEDMs is ongoing; however, improvement in model skill still lacks global treatments and its assessment is not integrated. Thus, the predictive performance of MEDMs is not strong and model uncertainties lack quantitative descriptions, limiting their application. Therefore, a large number of case studies concerning model skill should be performed to promote the development of a scientifi c and normative technical framework for the improvement of MEDM skill.

关键词： marine ecosystem dynamic models global optimization calibration model skill validation uncertainty

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Depositional Characteristics of Lake-Floor Fan of Cretaceous Lower Yaojia Formation in Western Part of Central Depression Region,Songliao Basin

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Journal of China University of Geosciences 2009年第4期20卷 731-745页

作者：辛仁臣李桂范冯志强梁江平林畅松 school of ocean sciences China University of Geosciences school of the Earth sciences and Resources China University of Geosciences Daqing Oilfield Company PetroChina school of Energy Resources China University of Geosciences

ABSTRACT： Based on the integrated subsurface data, including those of over 600 m drilled cores, more than 30 drilled wells and 600 km^2 three-dimensional （3D） seismic-reflection data of the study area, the characteristics of the lake-floor fan of lower Yaojia （姚家） Formation have been clarified. An evident lacustrine slope break and a steep slope belt developed in the west of Songliao （松辽） basin during depositional period of Qingshankou （青山口）-Yaojia formations （K2）. The slope gradient was about 15 m/kin. During the depositional period of lower Yaojia Formation, the lake shrank and the shore line of the western Songiiao basin shifted to the lacustrine slope-break. The wedge-shaped sediment body, which is interpreted as the lowstand system tract of SQyl （LSTy1）, developed in the area below the slope-break. The LSTy1 is pinched out in the west of the study area. As to the thickness of LSTy1, it is thicker in the east with 50 m in its thickness than in the west. The LSTy1, rich in sandstone, can be divided into lower part LSTy1L and upper part LSTy1u based on two onlap seismic reflection phases, and core and logging data clearly. The various sediments＇ gravity flow deposits developed and the complex of lake-floor fan formed in the LSTy1 under the slope-break in the western part of the central depression region. The lake-floor fan consists of various sediments＇ gravity flow deposits, including：（1） turbidity deposits with characteristics of Bouma sequences; （2） sand-bearing muddy debrite dominated by mud and mixed by sand; （3） mud-bearing sandy debrites characterized by dominated sand and mixed by mud; （4） sandy debris laminar flow deposits with massive or inclined bedding, and （5） sandy slump deposits developed as deformational sedimentary structure. During the lower lake-level period （LSTy1L）, the western clino-form region was erosion or sediment pass-by area; the terrigenous clasttc was directly trans-ported to deep-water area, converted to channelized sandy debris flo

关键词： lacustrine slope-break gravity flow deposit lake-floor fan Cretaceous Songliao basin

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Retrieve Sea Surface Salinity Using Principal Component Regression Model Based on SMOS Satellite Data

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Journal of ocean University of China 2016年第3期15卷 399-406页

作者： ZHAO Hong LI Changjun LI Hongping LV Kebo ZHAO Qinghui school of Mathematical sciences Ocean University of China Department of Marine Technology College of Information Science and Engineering Ocean University of China

The sea surface salinity(SSS) is a key parameter in monitoring ocean states. Observing SSS can promote the understanding of global water cycle. This paper provides a new approach for retrieving sea surface salinity from Soil Moisture and ocean Salinity(SMOS) satellite data. Based on the principal component regression(PCR) model, SSS can also be retrieved from the brightness temperature data of SMOS L2 measurements and Auxiliary data. 26 pair matchup data is used in model validation for the South China Sea(in the area of 4?–25?N, 105?–125?E). The RMSE value of PCR model retrieved SSS reaches 0.37 psu(practical salinity units) and the RMSE of SMOS SSS1 is 1.65 psu when compared with in-situ SSS. The corresponding Argo daily salinity data during April to June 2013 is also used in our validation with RMSE value 0.46 psu compared to 1.82 psu for daily averaged SMOS L2 products. This indicates that the PCR model is valid and may provide us with a good approach for retrieving SSS from SMOS satellite data.

关键词： sea surface salinity retrieved algorithm SMOS principle component regression

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Warming trend in northern East China Sea in recent four decades

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Chinese Journal of oceanology and Limnology 2009年第2期27卷 185-191页

作者：唐晓晖王凡陈永利李明悝 Institute of oceanology Chinese Academy of Sciences Graduate school of Chinese Academy of sciences Key Laboratory of ocean Circulation and Waves (KLOCAW) Chinese Academy of Sciences

Global warming has become a notable trend especially since an abrupt climate change in 1976. Response of the East China Sea （ECS） to the global warming trend, however, is not well understood because of sparse long-term observation. In this paper, hydrographic observation data of 1957-1996 are collected and reviewed to study climatological variability in northern ECS. Significant warming trends are found in both summer and winter. In summer, the average SST is about 0.46℃ higher during the period of 1977-1996 than that of 1957-1976, and the Taiwan Warm Current Water （TWCW） was strengthened. In winter, despite of the cooling effect in the coastal areas adjacent to the Changjiang （Yangtze） River Estuary （CRE）, the average SST increase was about 0.53℃ during the same period. The causes of this SST warming up in summer are different from in winter. The warming trend and intensification of the TWCW in summer were primarily influenced by the strengthening of the Kuroshio transport, while the warming in winter was mainly induced by the variability of the climate system.

关键词： global warming climate change East China Sea sea surface temperature long-termvariability

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Stratigraphic Architecture and Computer Modelling of Carbonate Platform Margin,Late Ordovician Lianglitage Formation,Central Tarim Basin

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Journal of Earth Science 2012年第4期23卷 627-638页

作者：李浩林畅松张燕梅张荣茜芮志峰黄理力 school of Energy Resources China University of Geosciences school of ocean sciences China University of Geosciences school of Information Engineering China University of Geosciences

According to the different geometries and reflected characteristics in the seismic sections, the carbonate platform margin of the northern slope can be summarized as three basic depositional architectures in the Late Ordovician Lianglitage （良里塔格） Formation of the Tazhong （塔中） uplift. The type one mainly located in the west of the carbonate platform margin, and it showed obvious imbricate progradation from the interior to the margin of the platform. The type two was in the middle of the carbonate platform margin, which showed retrogradational stacking pattern in the same transgres- sive systems tract period, and the slope strata of the platform margin showed progradational sequence in the highstand systems tract period. The type three located in the east of the carbonate platform margin, and it showed the parallel aggradational architecture. The crossing well section along the northern slope of the Tazhong carbonate platform showed that the depositional thickness became thinner from the east to the west. The thickest belt located in the east of the platform margin, and became thinner rapidly towards the basin and the platform interior. These indicated that the paleogeomorphology ofthe Tazhong uplift was probably high in the west and low in the east during the period of the Late Ordovician Lianglitage Formation. According to the interpretation of seismic profiles and the computer modelling result, the depositional architectures of sequence O31-2 showed aggradation, retrogradation and progradation from the east to the west of the carbonate platform margin during the transgression period. This meant that the accommodation became smaller gradually from the east to the west along the northern carbonate platform margin of the Tazhong *** difference of the accommodation was probably caused by the difference of tectonic subsidence. Also, computer-aided modelling can be used to deeply understand the importance of various control parameters on the carbonate platform dep

关键词： carbonate platform margin depositional architecture tectonic subsidence accommo-dation modelling.

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Variations in the eastern Indian ocean warm pool and its relation to the dipole in the tropical Indian ocean

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Chinese Journal of oceanology and Limnology 2009年第3期27卷 640-649页

作者：张启龙侯一筠齐庆华白学志 Institute of oceanology Chinese Academy of Sciences Key Laboratory of ocean Circulation and Waves(KLOCAW) Chinese Academy of Sciences The Graduate school of Chinese Academy of sciences

Based on the monthly average SST and 850 hPa monthly average wind data,the seasonal,interannual and long-term variations in the eastern Indian ocean warm pool(EIWP) and its relationship to the Indian ocean Dipole(IOD),and its response to the wind over the Indian ocean are analyzed in this *** results show that the distribution range,boundary and area of the EIWP exhibited obviously seasonal and interannual variations associated with the ENSO *** analysis suggests that the EIWP had obvious long-term trend in its bound edge and area,which indicated the EIWP migrated westwards by about 14 longitudes for its west edge,southwards by about 5 latitudes for its south edge and increased by 3.52×106 km2 for its area,respectively,from 1950 to *** correlation and composite analyses show that the anomalous westward and northward displacements of the EIWP caused by the easterly wind anomaly and the southerly wind anomaly over the eastern equatorial Indian ocean played an important and direct role in the formation of the IOD.

关键词： the Indian ocean warm pool ENSO dipole

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Variability of subduction rates of the subtropical North Pacific mode waters

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Chinese Journal of oceanology and Limnology 2011年第5期29卷 1131-1141页

作者：胡海波刘秦玉张媛刘伟 school of Atmospheric sciences Nanjing University Physical oceanography Laboratory & ocean-Atmosphere Interaction and Climate Laboratory Ocean University of China school of Atmospheric sciences Nanjing University of Information Science and Technology Center for Climatic Research and Department of Atmospheric and oceanic sciences University of Wisconsin-Madison

The climatology subduction rate for the entire Pacific is known, but the mechanism of interannual to decadal variation remains unclear. In this study, we calculated the annual subduction rates of three types of North Pacific subtropical mode waters using a general circulation model (LICOM1.0) for the period of 1958-2001. The model experiments focused on interannual variations of ocean dynamical processes under daily wind forcings and seasonal heat fluxes. The mode water formation region was defined by a potential vorticity minimum at outcrop locations. The model results show that two subduction rate maxima (>100 m/a) were located in the Subtropical Mode Water (STMW) and the Central Mode Water (CMW) formation regions. These regions are consistent with a climatologically calculated value. The subduction rate in the Eastern Subtropical Mode Water (ESTMW) formation region was smaller at about 75 m/a. The subduction rate shows clear interannual and decadal variations associated with oceanic dynamic variabilities. The average subduction rate of the STMW was much smaller during the period of 1981-1990 compared with other periods, while that of the CMW had a negative anomaly before 1975 and a positive anomaly after 1978. The variability agreed with Ekman and geostrophic advections and mixed layer depths. The interannual variability of the subduction rate for the ESTMW was smallest during 1970-1990, as a result of a weak wind stress curl. This paper explores how interannual signals from the atmosphere are stored in different parts of the ocean, and thus may contribute to a better understanding of feedback mechanisms for the Pacific Decadal Oscillation (PDO) event.

关键词： subduction rate North Pacific subtropical mode water ocean modeling

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