不同生活型蚯蚓对污泥处理的效果研究

研究报道了三种不同种蚯蚓接种后污泥的处理效果。28 天的培养实验表明: 接种蚯蚓, 特别是体型较大的威廉环毛蚓和杜拉蚓能提高污泥的pH 值, 减少污泥中有机物的含量。接种蚯蚓减少了污泥中全氮、全磷、全钾的含量, 深层种杜拉蚓显著降低了污泥中全氮和全磷含量, 较对照处理分别减少了14.3%和10.3%。接种威廉环毛蚓的处理较对照处理能显著增加水解性氮和速效钾的含量。接种杜拉蚓的处理吸收重金属的效果最佳, Cr 和Cu 含量均显著低于对照处理, 威廉环毛蚓次之, 但优于赤子爱胜蚓。结果显示, 在大部分项目中, 杜拉蚓和威廉环毛蚓的作用效果是要优于赤子爱胜蚓, 不同生活习性的蚯蚓对污泥净化效果会有着一定的不同。     

两种代表性蚯蚓对设施菜地土壤微生物群落结构及理化性质的影响

不同生态型蚯蚓的取食偏好和生境有所差异,因此蚯蚓的生态型差异可能关乎其对土壤性质的不同影响;有关不同生态型蚯蚓对土壤性质尤其是微生物学性质影响的研究有助于了解蚯蚓生态功能的作用机制。在野外调控试验的第4年采集土壤,研究了牛粪混施和表施处理下内层种威廉腔环蚓(Metaphire guillelmi)和表层种赤子爱胜蚓(Eisenia foetida)对设施菜地土壤微生物群落结构和主要理化性质的影响。结果表明,土壤微生物群落结构同时受到蚯蚓种类和牛粪施用方式的影响。牛粪表施时,两种蚯蚓均显著降低了菌根真菌、真菌生物量和原生动物生物量(P0.05);牛粪混施时,不同蚯蚓的影响有所差异,威廉腔环蚓明显增加了菌根真菌、真菌生物量和放线菌生物量,而赤子爱胜蚓的作用不明显。此外,两种蚯蚓均提高了土壤孔隙度、团聚体稳定性和土壤p H、矿质氮以及微生物生物量碳氮水平,但提高幅度取决于蚯蚓种类和牛粪施用方式。冗余分析表明蚯蚓影响下土壤微生物群落结构的变化与团聚体稳定性、p H、速效磷、矿质氮呈正相关,而与土壤容重呈负相关。     

春季树麻雀体内几种消化酶活性研究

应用酶学分析法测定了树麻雀Passer montanus春季的腺胃、肌胃、小肠、大肠、肝脏和胰脏组织中淀粉酶、蛋白酶和纤维素酶的活力.结果表明,不同组织中的消化酶活力差异显著,淀粉酶和蛋白酶以胰脏中活力最高,腺胃次之,纤维素酶均较低;同一组织中不同消化酶的活力差异显著,淀粉酶活性最高,蛋白酶次之,纤维素酶活力最低.这些差异提示消化酶活力大小与器官分化有关,并受食物组成的影响,因此产生了不同的酶活力分布.这是树麻雀长期适应东北地区寒冷环境的生存策略之一.     

中国巨蚓科蚯蚓的起源与演化

截至2017年中国已记录巨蚓科蚯蚓579种(亚种), 优势类群为远盲蚓属(Amynthas)与腔蚓属(Metaphire), 其丰富的物种多样性值得深入研究。近年来的研究指出联合形态分类与分子系统发育可较好地探讨中国巨蚓科蚯蚓的起源、分化与扩散。本文概述了中国巨蚓科蚯蚓物种的起源、分化时间以及扩散历程, 探讨了受精囊孔、盲肠形状等重要特征的演化, 分析了现行分类系统的缺陷。多项研究表明, 中国巨蚓科主要类群的祖先起源于中南半岛, 于白垩纪末期至新生代初期进入中国, 在新生代得以繁荣发展; 受精囊孔的对数或位置是多起源的, 盲肠形状演化中有祖征重现的现象, 故使用少数形态特征进行类群划分的现行分类系统有待改进。此外, 中国巨蚓科蚯蚓的具体演化机制及影响因素仍不明确。因此, 在未来研究中整合形态特征、分子数据与地理格局、地质历史及环境因子等信息, 定量分析类群演化与古地理、生物与非生物因素间的关系, 将有助于全面厘清中国巨蚓科蚯蚓演化的具体机制。     

阿苯哒唑对蚯蚓（Eisenia fetida）酸性磷酸酶、谷胱甘肽硫转移酶及腺三磷酶活性的影响

研究了蚯蚓在染毒2,7d和14d时,兽药阿苯哒唑(100～600mg/kg)对蚯蚓体及其不同部位的酸性磷酸酶(AP)、谷胱甘肽硫转移酶(GST)、腺三磷酶(Ca2 -ATPase)活性的影响。结果表明,阿苯哒唑对蚯蚓3种酶的活性均有显著影响,其中对AP和GST活性的影响比对Ca2 -ATPase的大。该药对AP和GST活性的抑制作用均随染毒时间的延长而加强,染毒浓度和时间表现出显著的互作效应。另外,AP活性也显著受到染毒浓度与蚯蚓部位的互作影响,影响最大的部位是蚯蚓前部;该药对Ca2 -ATPase活性的影响相对较小,浓度、时间和部位没有表现出明显的互作效应。     

Crystal structure of earthworm fibrinolytic enzyme component a: revealing the structural determinants of its dual fibrinolytic activity

Earthworm fibrinolytic enzyme component A (EFEa) from Eisenia fetida is a strong fibrinolytic enzyme that not only directly degrades fibrin, but also activates plasminogen. Proteolytic assays further revealed that it cleaved behind various P1 residue types. The crystal structure of EFEa was determined using the MIR method and refined to 2.3A resolution. The enzyme, showing the overall polypeptide fold of chymotrypsin-like serine proteases, possesses essential S1 specificity determinants characteristic of elastase. However, the beta strand at the west rim of the S1 specificity pocket is significantly elongated by a unique four-residue insertion (Ser-Ser-Gly-Leu) after Val217, which not only provides additional substrate hydrogen binding sites for distal P residues, but also causes extension of the S1 pocket at the south rim. The S2 subsite of the enzyme was partially occluded by the bulky side-chain of residue Tyr99. Structure-based inhibitor modeling demonstrated that EFEa's S1 specificity pocket was preferable for elastase-specific small hydrophobic P1 residues, while its accommodation of long and/or bulky P1 residues was also feasible if enhanced binding of the substrate and induced fit of the S1 pocket were achieved. EFEa is thereby endowed with relatively broad substrate specificity, including the dual fibrinolysis. The presence of Tyr99 at the S2 subsite indicates a preference for P2-Gly, while an induced fit of Tyr99 was also suggested for accommodation of bigger P2 residues. This structure is the first reported for an earthworm fibrinolytic enzyme component and serine protease originating from annelid worms.     

不同饵料对史氏鲟仔鱼消化酶活性的影响

用活饵料(水丝蚓)、商品饵料、添加消化酶制剂的商品饵料、活饵料与商品饵料交替使用(对照组)来投喂10～40日龄(DPH,Day＿past＿hatch)的史氏鲟仔鱼。其中对照组仔鱼体内蛋白酶活性和商品饵料组及添加消化酶组的差异极显著(P<0.01),与活饵料组差异不显著(P>0.05),活饵料组仔鱼蛋白酶活性与商品饵料组差异极显著(P<0.01),与添加消化酶组差异显著(P<0.05),商品饵料组和添加消化酶组之间仔鱼的蛋白酶活性差异不显著(P>0.05);各饵料组仔鱼的淀粉酶活性差异均不显著(P>0.05);活饵料组和对照组仔鱼的脂肪酶活力与商品饵料及添加消化酶组仔鱼的脂肪酶活性差异极显著(P<0.01),在这两组之间,仔鱼的脂肪酶活性差异均不显著(P>0.05)。     

月鳢消化器官指数及蛋白酶活性对饥饿的响应

经实验发现饥饿处理对月鳢各消化器官中蛋白酶活性有显著的影响,测定了实验组和对照组中月鳢各消化器官的蛋白酶活性的变化后,经统计分析,结果显示,在饥饿了4、8、12、16、20d后,胃、肠、肝胰脏中蛋白酶的活性与对照组相比较都出现了极显著变化（p〈0.01）;比胃重、比肝胰脏重以及比肠重在饥饿处理了4d和8d后并未出现显著变化（p〉0.05）,但在饥饿处理时间超过8d后,比肠重与对照组相比较出现了显著变化（p〈0.05）。     

Correlation between the activity of digestive enzymes and nonself recognition in the gut of Eisenia andrei earthworms

Earthworms Eisenia andrei, similarly to other invertebrates, rely on innate defense mechanisms based on the capability to recognize and respond to nonself. Here, we show a correlation between the expression of CCF, a crucial pattern-recognition receptor, and lysozyme, with enzyme activities in the gut of E. andrei earthworms following a microbial challenge. These data suggest that enzyme activities important for the release and recognition of molecular patterns by pattern-recognition molecules, as well as enzymes involved in effector pathways, are modulated during the microbial challenge. In particular, protease, laminarinase, and glucosaminidase activities were increased in parallel to up-regulated CCF and lysozyme expression.     

Species-specific differences in biomarker responses in two ecologically different earthworms exposed to the insecticide dimethoate

Earthworms ingest large amounts of soil and therefore are continuously exposed to contaminants through their alimentary surfaces. Additionally, several studies have shown that earthworm skin is a significant route of contaminant uptake as well. In order to determine effects of dimethoate, a broad-spectrum organophosphorous insecticide, two ecologically different earthworm species were used - Eisenia andrei and Octolasion lacteum. Although several studies used soil organisms to investigate the effects of dimethoate, none of these studies included investigations of dimethoate effects on biochemical biomarkers in earthworms. Earthworms were exposed to 0.001, 0.005, 0.01, 0.5 and 1 μg/cm(2) of dimethoate for 24 h, and the activities of acetylcholinesterase, carboxylesterase, catalase and efflux pump were measured. In both earthworm species dimethoate caused significant inhibition of acetylcholinesterase and carboxylesterase activities, however in E. andrei an hormetic effect was evident. Efflux pump activity was inhibited only in E. andrei, and catalase activity was significantly inhibited in both earthworm species. Additionally, responses of earthworm acetylcholinesterase, carboxylesterase and catalase activity to dimethoate were examined through in vitro experiments. Comparison of responses between E. andrei and O. lacteum has shown significant differences, and E. andrei has proved to be less susceptible to dimethoate exposure.     

Longterm persistence of proteolytic activities in frass of Blattella germanica increases its allergenic potential

Chromogenic microplate assays in 96 wells were used to determine the stability of enzyme activity in frass of Blattella germanica (Blattodea: Blattellidae). Frass samples were exposed to controlled conditions [temperature 15-35 °C and/or 53-100% relative humidity (RH)] and to household conditions (apartment). Exposure times were 0 (control), 90, 183 and 276 days. Starch digestion and cellulolytic activities decreased during exposure. Non-specific proteolytic activities were affected by changes in selective proteolytic activities. Activities towards AAPpNA and SA(3) pNA strongly increased at 100% RH, indicating the possible influence of microorganisms growing on frass. Activities towards BApNA and ArgpNA decreased with increasing decomposition time, whereas activity towards ZRRpNA was not influenced by exposure time. The largest decrease in activities towards ArgpNA and BApNA occurred at temperatures of 15 °C, 30 °C and 35 °C and at 100% RH. Activities towards BApNA and ZRRpNA were very stable under different temperature and RH conditions; this was confirmed by findings showing that these activities were stable in the experimental apartment. In comparison with the control, activities towards ZRRpNA and BApNA after 276 days decreased by 1% and 19%, respectively. The longterm persistence of proteolytic activities in cockroach frass increases their allergenic hazard potential.     

福寿螺和田螺消化酶活性比较

为比较福寿螺(Pomacea canaliculata(Lamarck,1828))和当地中国圆田螺(Cipangopaludina chinensis(Gray,1832))消化能力的差异,探索福寿螺成功入侵的机制,以田螺为对照,测定了1—4龄的福寿螺和田螺的胃和肝脏的消化酶——纤维素酶(羧甲基纤维素法)、淀粉酶(3,5-二硝基水杨酸法)和脂肪酶(滴定法)的活性。结果表明:1)相同年龄的福寿螺胃和肝脏中的消化酶活性明显高于田螺。其中,纤维素酶活性分别高出1.00—2.11倍、1.66—2.84倍;淀粉酶活性分别高出1.53—3.47倍、1.47—1.80倍;脂肪酶活性分别高出2.07—4.73倍、6.13—9.93倍。2)在生长发育过程中,福寿螺胃和肝脏中的消化酶活性变化幅度(51.2%—131.2%)明显高于田螺(23.3%—47.1%)。3)福寿螺的各种消化酶之间存在协同作用。如福寿螺的淀粉酶活性与脂肪酶活性呈极显著正相关(胃中r=0.736**、肝脏中r=0.867**)。此外,胃中的淀粉酶活性还与纤维素酶活性呈显著正相关关系(r=0.696*)。相应地,田螺胃中的淀粉酶和脂肪酶之间也存在显著的正相关关系(r=0.706*),而肝脏中的纤维素酶与脂肪酶活性呈显著负相关(r=-0.593*)。4)福寿螺对纤维素类和淀粉类物质都有较强的消化能力,且能较好地消化脂肪类物质,而田螺能消化纤维素类和淀粉类物质,对脂肪的消化能力却很弱。福寿螺的纤维素酶和淀粉酶活性分别是田螺的2.42和1.88倍,脂肪酶活性达到了5.66倍。可见,福寿螺具有较高的消化酶活性,且各消化酶之间存在正协同性。这可能是导致福寿螺食量大、食性杂,使其能快速生长和成功入侵的重要原因之一。