昆虫嗅觉相关蛋白及嗅觉识别机理研究概述

嗅觉是昆虫产生行为的基础之一,在长期进化的过程中昆虫形成了复杂的嗅觉系统,完成这一过程,需要有多种与嗅觉相关的蛋白参与,包括气味结合蛋白、化学感受蛋白、气味受体和感觉神经元膜蛋白等。了解昆虫感受外界信息的嗅觉机制可以帮助我们更好地理解昆虫识别配偶、天敌及寻找食物来源、产卵场地等行为特征,为进一步调控昆虫的行为、防控害虫侵袭、保护和利用有益昆虫奠定基础。本文综述了昆虫嗅觉相关的几类重要蛋白的生化特性和生理功能,并对昆虫气味分子的识别机制、气味分子在昆虫体内运输机制的最新研究进展进行了概述。     

养殖场气味的产生及其控制技术

对养殖场气味的来源、产生和组成成分进行了分析，对养殖场常见有味气体的气味特性进行了介绍，对目前国外常用的控制气味的方法进行了分析比较。以为我国养殖场气味的控制提供借鉴和指导。     

不同灭酶处理对燕麦气味和品质的影响

为选择合适的灭酶处理方法,通过电子鼻、感官评价和快速黏度分析等方法,对5种灭酶处理（焙炒、常压蒸煮、高压蒸煮、远红外处理和微波加热）对燕麦粉的气味、色泽和糊化特性的影响进行了研究。研究表明：燕麦粉的电子鼻主成分分析（PCA）二维和三维指纹图谱均可将不同灭酶处理的样品明显区分开来;样品的感官评价气味值由高到低依次为：焙炒组,红外组,高压蒸煮组,常压蒸煮组,微波组;样品白度检测结果由高到低依次为：红外组,微波组,焙炒组,蒸煮组,与色泽的感官评价结果基本一致,微波组和红外组的色泽明显优于其他3组的色泽。样品的糊化特性指标中,除糊化温度外,其他6项快速黏度分析（RVA）特征值均差异显著。由此说明,不同灭酶处理对燕麦粉的气味、色泽和糊化特性均有不同影响,应结合燕麦粉的不同用途选用不同的灭酶处理。     

基于DSP的苹果气味检测装置设计与实践

依据划分苹果等级的气味指标,由气味传感器阵列和DSP构成电子鼻系统采集苹果气味信号进行处理,建立苹果气味识别模型。研究气味传感器阵列的组成形式以及其采集到的数据,设计了传感器与DSP的接口数据采集电路以及视频显示接口电路。     

茎瘤固氮根瘤菌Azorhizobium caulinodansORS571基因组分泌蛋白的生物信息学分析

为了获取茎瘤固氮根瘤菌（AzorhizobiumcaulinodansORS571）的分泌蛋白，以便更深入地了解该菌的共生固氮作用，本研究采用SignalP、TMHMM、PSORTb、TargetP、LipoP、TatP和SecretomeP软件对该菌全部4717个蛋白序列进行分析预测。结果共识别了653个分泌蛋白，其中具有分泌型信号肽的蛋白54个，具有RR—motif型信号肽的蛋白1个，具有脂蛋白信号肽的蛋白2个和非经典分泌蛋白596个。该菌含信号肽分泌蛋白仅占全部蛋白的1．2％，低于其它固氮菌。在分泌蛋白中识别了核酸内切酶和核糖核酸酶等6个核酸酶。它们可能参与宿主植物遗传物质的降解，干扰宿主遗传代谢，进一步在宿主植物侵染过程中起到重要作用。此外还识别了超氧化物歧化酶、过氧化氢酶和谷胱甘肽S-转移酶等4个抗氧化酶。它们可能参与活性氧的清除以保护固氮酶，是该菌固氮过程的重要参与者。     

蓝园鲹深度水解过程中蛋白质降解研究

利用风味蛋白酶深度酶解蓝园鲹蛋白，通过比较酶解液的水解度曲线和蛋白质利用率曲线之间的差异、对TCA不溶性氮的变化趋势以及不同酶解时间的凝胶过滤图谱进行分析，探讨了深度酶解过程中蛋白质的降解。酶解6h后大部分蛋白质在酶的作用下降解为水溶性多肽，蛋白质利用率达到83。3％；6h以后蛋白质利用率增长速度降低，这可能是由于可被降解的底物含量降低。此后。风味蛋白酶以水溶性多肽为底物将其进一步降解为小分子肽和氨基酸；21h时水解度达到59．7％。21h以后水解度增长速度降低．这可能是由于亮氨酸氨肽酶难于分解氨基末端上带有甘氨酸和酸性氨基酸的肽。21h以后酶解的主要底物分子量范围在6214到10700的多肽。     

泛素/26S蛋白酶体途径及其在植物生长发育中的功能

泛素/26S蛋白酶体途径是一种蛋白高效降解途径,主要负责真核细胞内蛋白的选择性降解。泛素分子主要通过泛素活化酶E1、泛素结合酶E2和泛素-蛋白连接酶E3将靶蛋白泛素化,泛素化的蛋白最后被26S蛋白酶体识别和降解。本文介绍了泛素/26S蛋白体介导的特异性蛋白质降解途经,并对其在植物激素信号、光形态建成、植物衰老、自交不亲和反应、细胞周期调控、花的发育、生物钟节律和非生物胁迫响应中的功能最新研究进展进行了综述。     

GAF结构域的研究进展

GAF结构域广泛存在于各种蛋白中,其主要通过结合环核苷酸cGMP、cAMP、生色团和血基质等小分子作为信号分子、光或者气味受体,配合其他调节结构域稳定蛋白质构象和传递信号。本文简要综述了GAF结构域的基本特征、分类、结构及功能,为阐明一些重要信号转导途径及抗逆性研究提供了一定的理论依据。     

鸡肉在成熟过程中肌原纤维蛋白的降解机制研究

为了探讨肉在成熟过程中肌原纤维蛋白的降解机制,五只肉鸡分别宰杀后,迅速取出胸肉约3 g为0 d样品,其余肉样剪碎后随机分成六组,一组作为对照,另5组分别用30 mmol/L EGTA、20 mmol/L CaCl2、酶复合抑制剂、100μmol/L细胞凋亡酶3抑制剂（DEVD-CHO）、20 mmol/L CaCl2和酶复合抑制剂处理,在4℃成熟1、3、7 d后取样。通过SDS-PAGE和蛋白质印迹分析测定了骨骼肌中和肉嫩度高度相关的拌肌球蛋白（titin）、伴肌动蛋白（nebulin）、肌间线蛋白（desmin）、肌钙蛋白T（troponin-T）的降解变化。结果显示蛋白水解酶复合抑制剂和DEVD-CHO抑制了蛋白的降解,单独的钙离子加速蛋白降解。这表明肉的成熟是内源酶的作用,钙离子很可能通过激活钙激活酶发挥作用,另外细胞凋亡酶3也很可能参与了肉的成熟。     

畜禽血蛋白酶化与脱色工艺的应用研究

畜禽血经微生物蛋白酶水解，脱除血红素等工艺生产出的酶化脱血红素饲料蛋白，具有感观良好，气味清香，适口性强，消化率高等特点，粗蛋白含量在８２％－８６％，血红素脱除率在８０％以上，消除了血醒味。经酶化使大分子不易消化的蛋白质水解为小分子溶性的腙、胨；肽以及游离氨基酸。经测定可溶性氮达到８．２１％，占总氮的６１％，并含有较多的钙，磷以及其它矿物营养素，经科学配比可制成含蛋白质６０％左右的动物蛋白饲料，测     

Proteins as Agricultural Polymers for Packaging Production

Advantages, types, formation, and properties of agricultural packaging materials based on proteins, with examples, are reviewed in detail. Proteins have long and empirically been used to make biodegradable, renewable, and edible packaging materials. Numerous cereal and vegetable proteins (such as corn zein, wheat gluten, and soy proteins) and animal proteins (such as milk proteins, collagen, gelatin, keratin, and myofibrillar proteins) are commonly used to form agricultural packaging materials. Two technological processes have been investigated to make materials based on proteins: the “wet (or solvent) process” based on dispersion or solubilization of proteins in a solvent medium, and the “dry process” based on the thermoplastic properties of proteins under low water content conditions. The macroscopic properties (including solubility in water, mechanical properties, and barrier properties) of agricultural packaging materials based on proteins are dependent mainly on the structure of the macromolecular three-dimensional network and on interactions between proteins, plasticizers, and cross-linking agents.     

小峰熊蜂工蜂蛹期发育蛋白质组分析

本文采用双向凝胶电泳法对小峰熊蜂工蜂蛹期的3个发育期进行蛋白质组研究,结果表明小峰熊蜂工蜂蛹期的白眼期（A期）、褐眼期（B期）和黑眼期（C期）分别检测到77、81和59个蛋白点,特有蛋白分别为7个、6个和1个,共有蛋白为48个,A期到B期显著上调的蛋白有9个,显著下调的蛋白有3个,B期到C期显著上调的蛋白有8个,显著下调的蛋白有3个,A期到C期显著上调的蛋白有15个,显著下调的蛋白有2个。研究还发现有17个蛋白是在A期和B期表达而在C期关闭;有2个蛋白是在A期表达,B期关闭,在C期又表达。本研究初步揭示了小峰熊蜂工蜂从蛹期发育到成蜂过程中,不仅需要一些保守蛋白来调控,而目．还需要一此特异蛋白。     

Quantitative Determination of High Molecular Weight Glutenin Subunits of Hard Red Spring Wheat by SDS-PAGE. I. Quantitative Effects of Total Amounts on Breadmaking Quality Characteristics

Thirteen hard red spring wheat genotypes in which seven genotypes had the same high molecular weight (HMW) glutenin subunits (2*, 7+9, 5+10) were compared for their physical-chemical and breadmaking properties. These samples were categorized into three groups based on their dough mixing and baking performances as follows: the strong dough (SD) group (six genotypes), characterized by the strongest dough mixing (average stability, 35 min); the good loaf (GL) group (four genotypes), characterized by the largest loaf volume; and the poor loaf (PL) group (three genotypes), characterized by the smallest loaf volume. Total flour proteins were fractionated into 0.5M salt-soluble proteins, 2% SDS-soluble proteins, and residue proteins (insoluble in SDS buffer). SDS-soluble proteins, residue proteins, and total flour proteins were analyzed by SDS-PAGE and densitometry procedures to determine the proportions of HMW glutenin subunits, medium molecular weight proteins, and low molecular weight proteins in relation to the total amount of proteins. No differences in the amount of salt-soluble proteins were found among the different groups of samples. Solubilities of gluten proteins (total proteins minus salt-soluble proteins) in SDS buffer were related to the differences in dough strength and baking quality among the three groups. The SD group had the lowest solubility and the PL group had the highest. SDS-PAGE analysis showed that SDS-soluble proteins of the SD group contained a smaller amount of HMW glutenin subunits than those of the GL and PL groups. The highest proportions of HMW glutenin subunits in total flour proteins were found in the SD group, while the PL group had the lowest percentage of HMW glutenin subunits in their total flour proteins. These results showed that the total quantities of HMW glutenin subunits played an important role in determining the dough mixing strength and breadmaking performance of hard red spring wheats.     

Digestibility of food allergens and nonallergenic proteins in simulated gastric fluid and simulated intestinal fluid-a comparative study

Information on the comparative digestibility of food allergens and nonallergenic proteins is crucial when stability to digestion is to be used as a criterion to assess the allergenic potential of novel proteins. In this work, we compared the digestive stability of a number of food allergens and proteins of unproven allergenicity and examined whether allergens possess a higher stability than nonallergenic proteins of similar cellular functions, and whether there is a correlation between protein digestibility and allergenicity. The stability of groups of storage proteins, plant lectins, contractile proteins, and enzymes, both allergens and proteins with unproven allergenicity, in a standard simulated gastric fluid and a standard simulated intestinal fluid was measured. Food allergens were not necessarily more resistant to digestion than nonallergenic proteins. There was not a clear relationship between digestibility measured in vitro and protein allergenicity.     

Profiling of soluble proteins in wine by nano-high-performance liquid chromatography/tandem mass spectrometry

Wine proteins play an important role in a wine's quality as they affect taste, clarity, and stability. To enhance our understanding of the proteins in wine, nano-high-performance liquid chromatography (HPLC)/tandem mass spectrometry was used to profile soluble proteins in wine. Twenty proteins were identified from a Sauvignon Blanc wine including five proteins derived from the grape, 12 from yeast, two from bacteria, and one from fungi. The findings are somewhat peculiar at first glance, but reasonable explanations can account for the results. The grape proteins identified are less in number, which may be due to the availability of an incomplete database and possibly bentonite fining. The relatively large number of identified yeast proteins may be due to their complete protein database. The identified bacterial and fungal proteins could possibly be attributed to sources in the vineyard including natural infections and improper handling during harvest. The use of nano-HPLC/tandem mass spectrometry is an important tool for identifying wine proteins and understanding how they affect its characteristics.     

NaCl胁迫对菜用大豆种子膨大初期蛋白质表达的影响

采用蛭石栽培,对开花后10 d的菜用大豆 [Glycine max (L.) Merr.] 进行100 mmol/LNaCl处理,利用双向电泳（Two-dimensional gel electrophoresis, 2-DE）技术对胁迫5 d时的种子蛋白质进行分离,并对处理与对照2-DE图谱中蛋白质表达进行比较分析。在对照和处理的2-DE图谱上均检测到327个蛋白点,有28个差异表达蛋白,其中16个较对照显著上调,另外12个显著下调。利用基质辅助激光解吸离子化飞行时间质谱（Matrix-assisted laser desorption ionization time-of-flight mass spectrometry,MALDI-TOF-MS）对其中6个丰度差异较大（丰度变化在2.5倍以上）的蛋白进行分析,通过数据库检索,从中鉴定出5个蛋白质,分别是大豆球蛋白前体G2、肌动蛋白、大豆球蛋白前体G2相似蛋白、类-微管蛋白和Kunitz型胰蛋白酶抑制剂,并对这些蛋白质在NaCl胁迫下可能的作用进行了讨论。结果表明,NaCl胁迫对菜用大豆种子膨大初期的蛋白质代谢产生了显著影响,肌动蛋白、类-微管蛋白和Kunitz型胰蛋白酶抑制剂可能参与了对NaCl胁迫的应答反应。     

Fluorescence labeling of wheat proteins for determination of gluten hydrolysis and depolymerization during dough processing and sourdough fermentation

This study was undertaken to enable the determination of hydrolysis and functionality of proteins in situ during fermentation of wheat doughs. Wheat proteins were fractionated and labeled with fluorescein-isothiocyanate (FITC). Fluorescent proteins were incorporated into wheat sourdoughs inoculated with lactobacilli and into neutral and acid control doughs. Doughs containing fungal protease were furthermore evaluated. Doughs were analyzed by extraction and size exclusion chromatography analysis of sodium dodecyl sulfate soluble proteins. Labeled proteins exhibited characteristics comparable to native proteins, with respect to proteolytic degradation and polymerization. Proteolytic breakdown of proteins was enhanced at low pH. Glutenin subunits were incorporated into the gluten macropolymer at neutral pH. Polymerization of FITC proteins was not observed at low pH. Sourdoughs were comparable to acid control doughs, major effects were attributed to changes of pH, rather than microbial metabolism. A synergistic effect with respect to proteolytic activity was observed between fungal protease and L. pontis.     

Effect of Transglutaminase on Protein Electrophoretic Pattern of Rice,Soybean, and Rice‐Soybean Blends

The interactions taking place in composite dough containing rice flour and soybean proteins (5% w/w) in the presence of transglutaminase, an enzyme with cross‐linking activity, were studied using different electrophoretic analyses. The interaction between rice proteins and soybean proteins was intensified by the formation of new intermolecular covalent bonds catalyzed by transglutaminase and the indirect formation of disulfide bonds among proteins. The main protein fractions involved in those interactions were both β‐conglycinin and glycinin of soybean and the glutelins of the rice flour, although albumins and globulins were also cross‐linked. The addition of soybean proteins to rice flour improves the amino acid balance and they also might play an important role on the rice dough properties because soybean proteins interact with rice proteins, yielding protein aggregates of high molecular weight.     

Exploration of beer proteome using OFFGEL prefractionation in combination with two-dimensional gel electrophoresis with narrow pH range gradients

Two-dimensional gel electrophoresis in combination with mass spectrometry has already been applied successfully to study beer proteome. Due to the abundance of protein Z in beer samples, prefractionation techniques might help to improve beer proteome coverage. Proteins from four lager beers of different origins were separated by two-dimensional electrophoresis (2-DE) followed by tandem mass spectrometric analysis. Initially 52 proteins mostly from Hordeum vulgare (22 proteins) and Saccharomyces species (25 proteins) were identified. Preparative isoelectric focusing by OFFGEL Fractionator was applied prior to 2-DE to improve its resolution power. As a result of this combined approach, a total of 70 beer proteins from Hordeum vulgare (30 proteins), from Saccharomyces species (31 proteins), and from other sources (9 proteins) were identified. Of these, 37 proteins have not been previously reported in beer samples.