中国对虾血淋巴液中的凝集素

用饱和硫酸铵盐析、Ｓ－２００－ＨＲ凝胶层析、ＤＥＡＥ－ｓｅｐｈａｒｏｓｅ离子交换层析从中国对虾（ｆＰｅｎａｅｕｓ ｃｈｉｎｅｎｓｉｓ）血淋巴液中分离出１种凝集素,通过ＳＤＳ－ＰＡＧＥ测定,该凝集素由２个亚基组成,分子量分别为８００００、７５０００;此凝集素能凝集牛、马、鼠、兔、鸡、羊和人Ａ、Ｂ、Ｏ型红细胞,其凝集活性不被Ｄ－甘露糖、Ｄ－果糖、Ｄ－乳糖、乙酰半乳糖、神经氨酸、Ｄ－葡萄糖、Ｄ－半乳糖和     

荷包红鲤等鱼类血液涂片中“核影”的研究↑（*）

荷包红鲤等鱼类血液涂片中“核影”的研究ＳＴＵＤＩＥＳＯＦＮＵＣＬＥＡＲＳＨＡＤＯＷＩＮＴＨＥＢＬＯＯＤＳＭＥＡＲＯＦＴＨＥＲＥＤＰＵＲＳＥ－ＣＡＲＰＡＮＤＯＴＨＥＲＳ张丰旺虞鹏程马小平（南昌大学生物科学工程系，３３００４７）ＺｈａｎｇＦｅｎｇｗａｎ...     

低酶水解法提取无苦味鳀鱼水解蛋白

低酶水解法提取无苦味鳀鱼水解蛋白王长云，薛长湖，陈修白（青岛海洋大学水产学院，２６６００３）关键词鳀鱼，水解蛋白，无苦味，低酶水解法ＰＲＥＰＡＲＡＴＩＯＮＯＦＦＩＳＨＮＯＮ－ＢＩＴＴＥＲＨＹＤＲＯＬＹＳＡＴＥＦＲＯＭＡＮＣＨＯＶＹ（ＥＮＧＲＡＵＬＩＳ...     

自行往返远控潜吸式清淤机的发明与研究

自行往返远控潜吸式清淤机的发明与研究朱永兴（上海水产大学，２０００９０）关键词清淤机械，分类，行走，潜吸，远控ＩＮＶＥＮＴＩＯＮＡＮＤＳＴＵＤＩＥＳＯＮＡＵＴＯＭＡＴＩＣＤＩＳＴＡＮＴ－ＣＯＮＴＲＯＬＵＮＤＥＲＷＡＴＥＲ－ＣＯＬＬＥＣＴＩＮＧＭＡＣＨ...     

STUDIESONTHEOPTIMALREQUIREMENTSOFPANTOTHENICACID．BIOTIN．FOLICACIDANDB＿（12）INTHESHRIMPPENAEUSCHINENSI

ＳＴＵＤＩＥＳＯＮＴＨＥＯＰＴＩＭＡＬＲＥＱＵＩＲＥＭＥＮＴＳＯＦＰＡＮＴＯＴＨＥＮＩＣＡＣＩＤ．ＢＩＯＴＩＮ．ＦＯＬＩＣＡＣＩＤＡＮＤＢ＿（１２）ＩＮＴＨＥＳＨＲＩＭＰＰＥＮＡＥＵＳＣＨＩＮＥＮＳＩＳＬｉｕＴｉｅｂｉｎ，ＺｈａｎｇＪｉａｍｅｎｇ，Ｌ...     

荷包红鲤等鱼类血液中梭形细胞微细结构的研究↑（*）

荷包红鲤等鱼类血液中梭形细胞微细结构的研究ＳＴＵＤＩＥＳＯＮＴＨＥＦＩＮＥＳＴＲＵＣＴＵＲＥＯＦＳＰＩＮＤＬＥＣＥＬＬＩＮＴＨＥＢＬＯＯＤＯＦＴＨＥＲＥＤＰＲＵＳＥ－ＣＡＲＰＡＮＤＯＴＨＥＲＳ张丰旺胡成钰虞鹏程马小平（南昌大学生物科学工程系，３３０...     

日本海马仔鱼消化系统的组织学研究

日本海马仔鱼消化系统的组织学研究ＡＳＴＵＤＹＯＮＴＨＥＨＩＳＴＯＬＯＧＹＯＦＤＩＧＥＳＴＩＶＥＳＹＳＴＥＭＯＦＬＡＲＶＡＬＳＥＡ－ＨＯＲＳＥ张峰（大连水产学院，１１６０２３）ＺｈａｎｇＦｅｎｇ（ＤａｌｉａｎＦｉｓｈｅｒｉｅｓＣｏｌｅｇｅ，１１６０２３...     

大型培养中栅藻密度的几种临界值研究与应用

大型氵蚤培养中栅藻密度的几种临界值研究与应用ＳＴＵＤＹＡＮＤＡＰＰＬＩＣＡＮＴＩＯＮＡＢＯＵＴＳＥＶＥＲＡＬＣＲＩＴＩＣＡＬＶＡＬＵＥＳＯＦＤＥＮＳＩＴＹＯＦＳＣＥＮＥＤＥＳＭＵＳＳＰ．ＩＮＴＨＥＤＡＰＨＮＩＡＭＡＧＮＡＣＵＬＴＵＲＥ黄诚陈建秀（南京...     

INGESTIONANDEXCRETIONOFSEVERALANTIBACTERIALDRUGSBYTHEBRINESHRIMP（ARTEMIAPARTHENOGENETICA）1．TOXICITYT

ＩＮＧＥＳＴＩＯＮＡＮＤＥＸＣＲＥＴＩＯＮＯＦＳＥＶＥＲＡＬＡＮＴＩＢＡＣＴＥＲＩＡＬＤＲＵＧＳＢＹＴＨＥＢＲＩＮＥＳＨＲＩＭＰ（ＡＲＴＥＭＩＡＰＡＲＴＨＥＮＯＧＥＮＥＴＩＣＡ）１．ＴＯＸＩＣＩＴＹＴＯＡＲＴＥＭＩＡ，ＩＮＧＥＳＴＩＯＮＡＮＤＥＸＣＲ...     

鳖病研究的现状及其展望

鳖病研究的现状及其展望杨先乐，贺路，柯福恩（中国水产科学研究院长江水产研究所沙市４３４０００）关键词鳖病，病原，流行规律，防治ＳＴＡＴＵＳＱＵＯＡＮＤＰＲＯＳＰＥＣＴＦＯＲＲＥＳＥＡＲＣＨＩＮＧＤＩＳＥＡＳＥＳＯＦＳＯＦＴ－ＳＨＥＬＬＥＤＴＵＲＴＬＥ...     

金乌贼肌肉中三甲胺脱甲基酶的分离纯化及酶学性质

为了提取纯化金乌贼肌肉中的三甲胺脱甲基酶(TMAOase),本研究采用含有0.1 mol/L NaCl、pH 7.0、浓度为20 mmol/L的三羟甲基氨基甲烷(Tris)-醋酸缓冲液提取粗酶液,经透析、浓缩处理后,通过DEAE-52阴离子交换柱层析和Sephacryl S-300柱层析得到了纯化的TMAOase,并对其酶学性质进行了研究。结果显示,经Sephacryl S-300柱层析的TMAOase相比粗酶纯化了209.54倍;粗酶和纯化酶的最适温度分别为55和50°C,当温度高于最适温度时,酶活性开始出现显著下降,粗酶在80°C仍残留21.9%的活性;而纯化酶在80°C时,几乎检测不到酶活;粗酶和纯化酶的最适p H均为7.0,中性条件下表现稳定,在酸性和碱性条件下稳定性下降,p H为9.0时,粗酶残留60.7%的活性,而纯化酶的活性仅为20.5%。以双倒数作图法(Lineweaver-Burk法)测得纯化的TMAOase的Km值为22.8 mmol/L;经SDS-PAGE电泳分析,测得其分子量为21.3 ku;在化学物质中,柠檬酸和CaCl_2对酶活性具有显著的促进作用,H_2O_2和Na_2S对TMAOase活性有显著抑制作用。     

NAD-preferring malic enzyme: localization,regulation and its potential role in herring (<Emphasis Type="Italic">Clupea harengus)</Emphasis> sperm cells

Herring spermatozoa exhibit a high activity of NAD-preferring malic enzyme (NAD-ME). This enzyme is involved in the generation of NADH or NADPH in the decarboxylation of malate to form pyruvate and requires some divalent cations to express its activity. In order to confirm that NAD-ME isolated from herring sperm cells is localized in mitochondria, we performed immunofluorescent analysis and assayed spectrophotometrically the malic enzyme reaction. Production of polyclonal rabbit antibodies against NAD-ME from herring spermatozoa enabled identification of mitochondrial localization of this enzyme inside herring spermatozoa. The kinetic studies revealed that NAD-ME was competitively inhibited by ATP up to tenfold. Addition of fumarate reversed ATP-dependent inhibition of NAD-ME to 55 % of its maximum activity. The pH-dependent regulation of malic enzyme activity was also examined. Malic enzyme showed maximum activity at pH near 7.0 in all studied conditions. Finally, the role of malic enzyme activity regulation in mitochondria of herring sperm cells was discussed.     

中国对虾幼体消化酶活力的实验研究

以酶学分析方法测定了中国对虾各期幼体几种消化酶活力，实验结果表明，在中国对虾幼体发育过程中，五种消化酶活力表现出四种变化模式，其中胃蛋白酶和类胰蛋白酶活力逐渐增大，淀粉酶活力呈下降趋势，纤维素酶和脂肪酶活力极微，在食性转换过程中，胃蛋白酶、类胰蛋白酶和淀粉酶出现较明显的变化。中国对虾幼体消化酶活力对饵料中的营养物质有着明显的适应性，而且饥饿实验表明消化酶活力受个体发育的影响。作者认为中国对虾幼体消     

The mudskippers Periophthalmodon schlosseri and Boleophthalmus boddaerti can tolerate environmental NH3 concentrations of 446 and 36µM, respectively

A lipase was purified from the extract of the delipidated powder of red sea bream hepatopancreas to nar homogeneity by fractional precipitation with ammonium sulfate and sequential chromatography on first anion-exchange-, hydrophobic- and second anion-exchange columns followed by gel filtration and anion-exchange HPLC. The final enzyme preparation showed a single band with an apparent molecular mass of approx. 64 kDa by sodium dodecyl sulfate-polyacrylamid e gel electrophoresis. The purified enzyme had a pH optimum in the range of pH 7.0–9.0. Using -nitrophenyl myristate or triolein as a substrate, the enzyme required the presence of sodium taurocholate or sodium cholate for its activity. No activity was observed in the presence of sodium deoxycholate. The enzyme preferentially hydrolyzed ethyl esters of polyunsaturated fatty acid, such as arachidonic acid and eicosapentaenoic acid which were resistant to porcine pancreatic lipase. These results strongly suggest that the enzyme purified from the hepatopancreas of red sea bream is homologous to mammalian bile salt-activated lipase.     

Partial purification and characterization of extracellular metalloproteases with caseinolytic, aminopeptidolytic and collagenolytic activities from Vibrio anguillarum

Abstract. Proteases produced by Vibrio anguillarum were isolated from culture supernatant by ultrafiltration, gel chromatography and ion exchange chromatography. The enzyme(s) were shown to be collagenolytic when assayed with native collagen substrates. In addition, the enzyme(s) hydrolysed azocasein, azocollagen, the collagenase substrate 4-phenylazobenzyloxycarbonyl-Pro-Leu-Gly-Pro-D-Arg and the aminopeptidase substrate L-Leu-pNA effectively. Separation of the proteases by Mono Q ion exchange chromatography and native polyacrylamide gel electrophoresis revealed four distinct protein bands containing caseinase activity. However, only two of the bands showed aminopeptidase activity. The aminopeptidase activities could be separated from the caseinase activities by isoelectric focusing. Secreted proteases of different serotypcs of V. anguillarum showed a heterogeneous caseinolytic pattern. The molecular mass of the major enzyme was estimated at 35kDa as determined by its mobility on SDS-polyacrylamide gels. Serine protease inhibitors like PMSF, TPCK, TLCK and benzamidine had no inhibitory effects on the proteolytic activity when tested with azocasein as substrate. However, the enzyme was strongly inhibited by metal chelators like EDTA and 1, 10-phenanthroline. Also, normal salmon scrum and purified α₂-macroglobulin from salmon serum strongly inhibited the caseinolytic activity of the enzyme.     

Purification and some properties of alanine racemase from the marine gastropod <Emphasis Type="Italic">Cellana grata</Emphasis>

ABSTRACT:   High levels of free d -alanine were found in the muscle of a marine gastropod Cellana grata that inhabited the intertidal zone, and alanine racemase activity was detected in the muscle. The authors purified alanine racemase from the muscle of C. grata to characterize its enzymological properties. The molecular mass of the enzyme was estimated to be 40.5 kDa by sodium dodecylsulfate-polyacrylamide gel electrophoresis and 41.4 kDa by gel filtration, suggesting that the enzyme was monomeric in nature. Kinetic experiments, performed using the purified enzyme, revealed that the Lineweaver-Burk plot for d -alanine as a substrate resulted in a K _m value of 20.4 mM, and the value for l -alanine was 43.0 mM. Of the several types of amino acids tested, alanine was found to be the specific substrate for the enzyme. In the measurement of alanine racemase activity, exogenous pyridoxal 5'-phosphate (PLP) was not required for the enzyme activity; however, aminooxyacetic acid, hydroxylamine and phenylhydrazine, which inhibit PLP-dependent enzymes, strongly inhibited the enzyme activity. These results suggest that the enzyme is PLP-dependent. This is the first report on the purification and some properties of alanine racemase in a marine gastropod.     

Purification of transglutaminase from scallop striated adductor muscle and NaCl-induced inactivation

SUMMARY: Tissue type transglutaminase (TGase) was purified from scallop striated adductor muscle with successive chromatographies of DE-52 cellulose, Sephacryl S-300, and Mono Q columns. The yield and purification of the enzymatic activity was 16.6% and 101.9-fold, respectively. The molecular mass of purified enzyme was estimated to be 95 kDa by sodium dodecylsulfate–polyacrylamide gel electrophoresis analysis. Scallop TGase was Ca²⁺-dependent and strongly inactivated by ρ-chloromercuribenzoic acid, N -ethylmaleimide, Cu²⁺, and Zn²⁺, meaning it belongs to the thiol group of enzymes as well as being a mammalian enzyme. When scallop TGase was incubated in 0.5 M NaCl without substrate for 2 h at 20°C and pH 7.5, enzymatic activity decreased to 14.4% of its original. However, a conformational change in the TGase molecule was not detected by either fluorescent, ultraviolet, and circular dichroism spectra analyses compared to the enzyme incubated without NaCl. In addition, the enzyme inactivated by NaCl was partially recovered by the dilution of salt concentration, which means that the NaCl-induced inactivation process is reversible to some extent. These results suggest that NaCl-induced modulation of the TGase molecule occurs via a small conformational change.     

Alanine racemase activity in the microalga <Emphasis Type="Italic">thalassiosira</Emphasis> sp.

ABSTRACT:   In this paper, the authors report the detection of alanine racemase activity in the marine diatom Thalassiosira sp. Since the Thalassiosira sp. was cultured under germ-free conditions, it appeared that D-alanine was not derived from bacteria but was produced through catalysis by algal alanine racemase. The rate of conversion of L-alanine to D-alanine was approximately the same as that for the reverse reaction, and the enzyme catalyzed the equilibration of the D- and L-forms. The crude enzyme preparation obtained from the cells at the stationary phase of the growth cycle had an optimal pH of approximately 9.5. The Lineweaver–Burk analysis showed that the K _m for D- and L-alanine was 16.5 mM and 29.4 mM, respectively. It appears that the enzyme is highly specific for D- or L-alanine because it does not catalyze the racemization of other amino acids. In addition, after gel filtration, the enzyme did not require exogenous pyridoxal 5'-phosphate (PLP) for its activity, however, the effects of several chemicals suggest that the enzyme may be PLP-dependent. The enzyme is more similar to that found in invertebrates when compared with that found in bacteria. This is the first report on the occurrence of alanine racemase activity in the microalga Thalassiosira sp.     

海洋微生物低温酶特性及其在工业中的潜在用途

依据近年来关于低温酶的研究资料，讨论了低温酶的研究现状，对产低温酶海洋细菌的种类、嗜冷特性、适应低浊的机制以及对其在工业上的应用作一评述。     

Isolation and characterisation of two extracellular metalloproteases from Aeromonas salmonicida ssp. salmonicida

Two extracellular metalloproteases were purified from a culture filtrate derived from Aeromonas salmonicida ssp. salmonicida . One enzyme, leucine aminopeptidase (LAP), which had a molecular mass 37 kDa, hydrolysed aminoterminal l -leucine and l -phenylalanine. The activity was inhibited by 1,10-o-phenanthroline, but not by EDTA. The addition of excess Zn²⁺ to an o-phenanthroline-inhibited enzyme restored most of its activity. The peptidase was temperature stable, and had an optimum temperature and pH of 60 °C and 8, respectively. The other enzyme, metalloprotease 3 (MP3), which had a molecular mass 20 kDa, was an endoprotease, and hydrolysed azocoll and hide powder-azure, but not gelatine. The MP3 enzyme had an optimum temperature and pH of ≈40 °C and 7.5, respectively, and a cationic isoelectrical point.