适应海南热带海洋环境产脂肪酶菌株的筛选及产酶条件研究

从海南热带海水中分离筛选得到10株产脂肪酶菌,其中菌株LD-1302产脂肪酶活性最高。根据16S r DNA序列分析和生理生化试验结果,鉴定该菌为地衣芽孢杆菌Bacillus licheniformis。对该菌株的产酶条件进行优化,在p H 8、温度37℃、盐度32的条件下,经橄榄油诱导,起始浓度为3.75×105CFU/m L的LD-1302摇瓶发酵48 h时产脂肪酶活最高,脂肪酶活可达(34.97±1.45)U/m L。     

海产品中蛋白酶产生菌的选育及产酶条件研究

从海产品虾和蟹中分离出蛋白酶产生菌共37株，其中YM007菌株蛋白酶生产活力较高，为194．6U／mL。以YM007为出发菌株，通过物理和化学方法复合诱变，获得了YM079号菌株。对其产酶条件的研究结果表明：它的最适产酶温度为35℃，最适生长pH为7．0，经过190r／min摇床培养36～40h，其产酶活力为240U／mL，比出发菌株的产酶活力提高了22％。该菌株经发酵的粗酶液最适作用pH为7．0，最适作用温度是45℃，是一种中温型中性蛋白酶。     

深海适冷菌SM9913产生的低温蛋白酶

从1855m深的深海泥样中分离纯化得到200多株分泌蛋白酶的适冷菌，其中3株产低温蛋白酶，本文对其中一株Pseudomonas sp.SM9913(P.SM9913)生长的适冷性和它产生的蛋白酶的适低温特性进行了研究。该菌株能够在0℃正常生长，其最适生长温度为15℃，最高生长温度为35℃。为一株适冷菌。该菌株所产蛋白酶的比合成速率在10℃时最高，催化酪蛋白水解的最适温度为35℃，在0℃仍具有3％的酶活力。最适pH为8．0。该蛋白酶的热稳定性很低，在40℃保温10min即丧失85％的活力，40℃时的半衰期为6min，为一典型的低温酶。抑制剂试验表明，该蛋白酶为金属蛋白酶。     

一株虹鳟源枯草芽孢杆菌的分离鉴定及生物学特性研究

为筛选对虹鳟(Oncorhynchus mykiss)有潜在益生效果的菌株,本研究从健康虹鳟幼鱼肠道中分离到1株潜在益生菌株RT-BS07,采用形态学观察和分子特征分析对该菌株进行了鉴定,并评价了该菌株的抑菌性、耐受性、黏附性和安全性。形态学观察显示,菌株RT-BS07为革兰氏阳性杆菌,有圆形或椭圆形芽孢。16S rRNA比对结果显示,该菌株与枯草芽孢杆菌(Bacillus subtilis)NCBI3610株的同源性为99.86%。结合16S rRNA基因序列分析和形态学观察结果,确定菌株RT-BS07为枯草芽孢杆菌。菌株RT-BS07具备产蛋白酶和纤维素酶能力,其酶活力分别为(0.039±0.002)和(0.393±0.002)U/mg;该菌株可有效抑制温和气单胞菌(Aeromonas sobria)、杀鲑气单胞菌(A.salmonicida)和鲁氏耶尔森氏菌(Yersinia ruckeri)等致病菌。菌株RT-BS07在pH为2~10 LB液体培养基中均可存活;在盐度为2%~8%条件下存活率为5.70%~93.28%,其存活率随盐度升高而降低。体外黏附试验结果表明,菌株RT-BS07可大量黏附在虹鳟前肠黏膜,不破坏肠道组织完整性,对左氟沙星、环丙沙星、氧氟沙星和链霉素等18种抗菌药物敏感。本研究分离筛选得到的枯草芽孢杆菌RT-BS07株具有产消化酶性能,其抗逆性能强,对虹鳟无毒害作用,可作为虹鳟健康养殖及益生菌制剂研发源益生菌候选株。     

产胞外黑色素海洋菌的鉴定及发酵条件优化

从山东近海海域沉积物的微生物筛选中获得了一株高产胞外黑色素的菌株QJNY82,通过对该菌株菌落形态特征观察、生理生化检验及16S rDNA序列测定,初步确定该菌株为发光杆菌属细菌.通过对菌株QJNY82的胞外产物进行红外光谱分析,得到该细菌的胞外产物为黑色素,纯化后的黑色素的红外光谱图与标准黑色素（SIGMA）的红外光谱图一致,且该细菌所产黑色素的理化性质与标准黑色素具有一致性.该海洋菌株具有产黑色素速度快,产量高且不需要L-酪氨酸诱导的特点,而且经L-酪氨酸诱导后,可显著提高菌株QJNY82胞外黑色素的产量,在L-酪氨酸的含量为0.75 g/dm3、盐度为30、pH值为8.0、温度为28℃的条件下,菌株黑色素产量是未加L-酪氨酸的3.5倍,其产量达1.325g/dm3.鉴于菌株QJNY82具有产黑色素的特性,将成为发光杆菌属的一个新的菌种资源.     

我国近海中度嗜盐菌的分离筛选及其产酶多样性分析

为了解我国近海中度嗜盐菌系统发育多样性及产酶特性,从天津、山东、江苏、福建、海南等地近海采集样品为研究对象,分离筛选得到108株中度嗜盐菌,其中有26株至少产一种酶。通过对其形态特征、生理生化、16SrRNA基因序列及系统进化树进行分析,将26株菌鉴定为细菌域的Halomonas、Idiomarina、Virgibacillus、Pontibacillus、Oceanobacillus、Halobacillus和Marinilactibacillus属的菌株。它们与相应属的模式菌株16SrRNA基因序列相似性在97%~100%不等,其中有些菌株可能代表不同的分类单元。底物特异性试验表明,分离的26株中度嗜盐菌13株产蛋白酶,19株产淀粉酶,13株产酯酶,4株产纤维素酶。其中6株产3种酶,11株产2种酶。研究结果表明中度嗜盐菌具有系统发育和产酶多样性,同时蕴藏着较多新的微生物类群,为嗜盐微生物资源应用开发提供了参考。     

一株产低温右旋糖苷酶海洋细菌的筛选和鉴定

从连云港海域筛选得到一株产低温右旋糖苷酶的菌株LP621,经形态特征、生理生化特征以及16S rDNA序列分析和鉴定,该菌株为Pseudoalteromonas tetraodonis.该茵产生低温右旋糖苷酶的最适作用温度为30℃,在80℃保温2.5 h后该酶仍具有40％以上的活性.目前尚无Pseudoalteromo...     

4株海洋红球菌产类胡萝卜素分析及其全基因组测序

以源于东太平洋海水的4株红球菌分离菌Rhodococcussp. EPR-134、Rhodococcus sp. EPR-147、Rhodococcus sp. EPR-157和Rhodococcus sp. EPR-279为研究对象,开展了菌株的色素提取和色素全波长扫描,并基于全基因组测序分析了4株细菌类胡萝卜素代谢通路中的相关基因。色素全波长扫描结果显示,菌株EPR-134不具备类胡萝卜素产生能力,而其它3株红球菌能够产生类胡萝卜素,且所产类胡萝卜素组分不同。基因组分析表明,4个细菌基因组中存在较为完整的促使类胡萝卜素形成的基因簇。对菌株参与番茄红素形成的3个关键基因crt E、crt B和crt I的氨基酸序列同源性两两比对分析表明,菌株EPR-134 3个基因氨基酸序列与其它3个菌株相应基因氨基酸序列同源性最低,这可能是导致该菌株不产类胡萝卜素的关键原因。该研究结果为产类胡萝卜素红球菌的遗传改造,以及为产类胡萝卜素工程菌的构建奠定了前期基础。     

对虾肠道中产蛋白酶菌株的筛选、鉴定及其产酶特性初步研究

本文对从健康的凡纳滨对虾、日本囊对虾肠道中初步分离得到的58株菌进行产蛋白酶能力测试,筛选得到产酶能力较强的3株菌,经生理生化和16SrDNA序列分析,初步鉴定为蜡样芽孢杆菌(SDMG9)、沙福芽孢杆菌(SDVG4)及蜡样芽孢杆菌(SQVG9)。生长及产酶条件优化表明菌株SDMG9的最适生长温度为28-40℃、pH为5.5-6.5、盐度为0-20,最适产酶温度为28℃、pH为9.5、盐度为0;菌株SDVG4的最适生长温度为28-40℃、pH为5.5-8.5、盐度为10-20,最适产酶温度为40℃、pH为5.5、盐度为10;菌株SQVG9的最适生长温度为28-40℃、pH为6.5-8.5、盐度为0-20,最适产酶温度为28℃、pH为7.5、盐度为10。经溶血试验与药敏试验检测表明三株菌均无显著溶血圈且所含耐药因子较少,不具备潜在的致病性,为后续对虾肠道益生菌的筛选及应用提供了科学依据。     

杂色鲍Haliotis diversicolor溃疡症病原菌的研究

从患病杂色鲍Haliotisdiversicolor病灶上以TCBS及 2 2 1 6E平板划线各分离到两株致病性细菌 ,经人工感染实验可出现与自然发病相同的症状 ,并从感染鲍分离到同一菌株 ,证明该两株菌为杂色鲍溃疡症的病原菌。这两株菌的特征具明显一致性 :革兰氏阴性 ,短杆状 ,极生单鞭毛。氧化酶和过氧化氢酶阳性 ,淀粉酶、明胶酶阳性及脲酶阴性 ,可还原硝酸盐 ,不能利用柠檬酸 ,不产生吲哚和硫化氢 ,MR阳性、V .P实验阴性 ,发酵葡萄糖产酸不产气 ,O/ 1 2 9敏感 ,0 %和 1 0 %胰胨水中不生长。经鉴定该病原菌为亮弧菌ⅡVib riosplendidus-Ⅱ。还对亮弧菌进行了药敏试验 ,该菌对氨苄青霉素、氯霉素、复方新诺明等药物非常敏感 ,这些药物可作为防治该病的首选药物     

Assessing the Validity of Seismo-Acoustic Predictor Equations for Obtaining Seabed and Sub-Surface Sediment Physical Properties

The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths.     

A Review of Some Environmental Issues Affecting Marine Mining

This article reviews information recently available from existing marine and coastal mining for responses to environmental issues affecting marine mining at different depths. It is particularly but not exclusively concerned with those issues affecting seabed biodiversity impact and recovery. Much information has been gathered in the past 10 years from shallow mining operations for construction aggregate, diamonds, and gold, from coastal mines discharging tailings to shallow and deep water, and from experimental deep mining tests. The responses to issues identified are summarized in a series of eight tables intended to facilitate site-specific consideration. Since impacts can spread widely in the surface mixing layer SML, and can affect the biologically productive euphotic zone, the main issues considered arise from the depth of mining relative to the SML of the sea. Where mining is below the SML, the issue is whether it is environmentally better to bring the extraction products to the surface vessel for processing (and waste discharge), or to process the extraction products as much as possible on the seabed. Responses to the issues need to be sitespecific, and dependent on adequate preoperational environmental impact and recovery prediction. For deep tailings disposal from a surface vessel, there are four important environmental unknowns: (1) the possible growth of "marine snow" (bacterial flocs) utilizing the enormous quantities of fine tailings particles (hundreds or thousands of metric tons per day) as nuclei for growth, (2) the possibility that local keystone plankton and nekton species may migrate diurnally down to and beyond the depth of deep discharge and hence be subjected to tailings impact at depth, (3) the burrow-up capability of deep benthos and their ability to survive high rates of tailings deposition, and (4) the pattern and rate of dispersion of a tailings density current through the deep water column from discharge point to seabed. Actions to obtain relevant information in general and site-specifically are suggested.     

Increased Particle Fluxes at the INDEX Site Attributable to Simulated Benthic Disturbance

Particle fluxes were measured 7 m above the sea bottom during the predisturbance, disturbance, and postdisturbance periods by using time series sediment traps attached to seven deep-sea moorings deployed in the INDEX experiment site in the Central Indian Basin. The predisturbance particle fluxes varied between 22.3 to 55.1 mg m -2 day -1 . Increased and variable particle fluxes were recorded by the sediment traps during the disturbance period. The increase observed was 0.5 to 4 times more than the background predisturbance fluxes. The increases in particle fluxes (~4 times) recorded by the sediment trap located in the southwestern direction (DMS-1) were the greatest, which could be the result of preferential movement of resuspended particles generated during the deep-sea benthic disturbance along the general current direction prevailing in this area during the experimental period. Also, the traps located closer to the disturbance area recorded greater fluxes than did the traps far away, across the Deep Sea Sediment Resuspension System path. This variability in recorded particle fluxes by the traps around the disturbance area clearly indicates that physical characteristics such as grain size and density of the resuspended particles produced during the disturbance had an important effect on particle movement. The postdisturbance measurements during ~5 days showed a reduction in particle fluxes of ~50%, indicating rapid particle settlement.     

海上大直径钢管桩打桩过程中桩周土强度弱化研究

海上大直径钢管桩打桩过程中,桩周土体受到强烈扰动而发生强度弱化,掌握桩周土体强度弱化规律对于准确预测打桩过程、保证工程安全具有重要意义。为研究土体强度弱化规律,开展了环剪试验模拟打桩对桩周土体的扰动,测试土体强度随剪切速率的变化规律,建立了描述土体强度弱化规律的拟合公式,引入到打桩分析软件中。研究结果表明：土体的强度折减程度不仅与土体本身的性质有关还受到土体的埋深和剪切速率的影响,埋深越深土体强度折减程度越低,剪切速率越高土体强度折减越高,在打桩分析中可采用这里推荐的线性折减方法来模拟不同深度处土体强度的折减规律。     

Determination of In Situ Sediment Shear Strength from Advanced Piston Corer Pullout Forces

The advanced piston corer (APC) has been used by the Ocean Drilling Program since 1985 for recovering soft sediments from the ocean floor. The pullout force measured on extracting the core barrel from the sediment is shown to correlate with the average shear strength of the sediment core measured in the ship's laboratory. A simple rule of thumb is derived relating the shear strength of the sediment to the pullout force. Multiple APC holes at individual sites allow the consistency of the pullout measurements to be assessed. The effects of different operational procedures during APC coring are also explored. Although generally applicable, the correlation between pullout force and laboratory measurements of shear strength breaks down for some APC holes, possibly because of the disturbance of some sediment types during the APC coring process. A better understanding of the physical process of APC coring, and its effect on the properties of the sediment both inside and immediately outside the core barrel, would indicate what confidence can be put on the measurement of pullout force as a way of evaluating the in situ shear strength of deep sea sediments.     

Interannual Sea Level Variations and Annual Tides in the Northwestern Pacific

Specific properties of the interannual sea level variations and annual tides in the Northwestern Pacific were studied. Several tide stations were monitored. The monthly mean sea level for the year of 1995 was analyzed at each tide station. A seismic event in 1995, some tectonic activity around the subject area, and the Kuroshio (the oceanic western boundary current) may possibly contaminate results which would have occurred from the astronomical annual tide alone.     

Flow Cytometric Analysis of Coastal Lagoon Bacterioplankton and Picophytoplankton: Fixation and Storage Effects

The effect of different fixation and storage protocols on the flow cytometric (FCM) simultaneous analysis of bacterioplankton and phytoplankton in coastal seawater samples (Mediterranean coastal lagoons) was investigated. FCM measurements (cell number, fluorescence and scatter characteristics) were obtained through DAPI staining. Three fixatives [glutaraldehyde (GA), formaldehyde (FA) and paraformaldehyde (PFA)] and two storage (3 months duration) methods (5 °C and −196 °C) were tested. Two dominant populations were detected in studied samples: bacteria and eukaryotic picophytoplankton. Adding fixatives (2% final concentration) appears necessary to obtain FCM exhaustive counts of all the bacteria and phytoplanktonic cells. This was related to the permeation effect of fixatives which allowed a better DAPI staining of the cells. Maximum fluorescence, i.e. optimal staining of the cells was obtained with FA or PFA, and significant lower fluorescences with GA. Fixed samples stored at 5 °C induced rapid cell loss. Only storage in liquid nitrogen of samples fixed with FA or PFA, allows mid-term (≥4 months) preservation of bacteria or picophytoplankton cell numbers, and limited evolution of DAPI-induced fluorescence and scatter characteristics.     

《Acta Oceanologica Sinica》Vol. 33(2014) contents

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INFORMATION FOR AUTHORS

<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology,