Cathelicidins类抗菌肽研究进展

论述了动物先天免疫中的重要成分——抗菌肽家族之一的cathelicidins家族的基因结构特点及其表达；生物学活性、作用机理等方面的特点，并对其应用前景做了展望。     

鸡源Cathelicidins家族抗菌肽研究进展

Cathelicidins (CATHs)是一类具有抗感染和免疫调节等活性的多功能抗菌肽,广泛分布于不同动物体内,在宿主抵御病原时入侵发挥极其重要的作用。近年来,鸡源CATHs活性及应用的研究得到迅速发展,其广谱抗菌活性及独特的杀菌机制使其不易产生耐药性,具有成为新一代抗菌和免疫调节药物的潜力。现对鸡源CATHs的结构与活性的关系、分布与表达、抗微生物活性、免疫调节活性等方面的研究进展进行综述,并对其应用前景进行了分析。     

猪源抗菌肽及其应用前景

抗菌肽是近年来发现的广泛存在于自然界中的一类阳离子抗菌活性肽,多数抗菌肽具有分子小、带正电、两亲性、抗菌谱广等共同特点。防御素和Cathelicidins是哺乳动物体内的两大主要抗菌肽家族,在哺乳动物的机体防御中起着重要的作用。猪源抗菌肽的一般性质、基因及其表达、在宿主防御中的作用、作用机理及研究前景将在文中予以概述。     

猪源抗菌肽的研究进展

近年来微生物的耐药性问题一直困扰着世界的养殖业。长期、广泛、不加选择地使用抗生素药物和抗生素饲料而导致一系列耐药微生物的出现给细菌性疾病的控制和治疗带来了极大的麻烦和困难，同时也给人类的健康带来潜在的威胁，因此研制新一代的抗菌药物便成为当今一项新的课题。目前一种     

猪小肠粘膜抗菌肽

目前已经从猪体内发现12种以上不同的抗菌肽,这些抗菌肽具有不同的螺旋结构,分子量相对较小,小于10kDa,但对多种微生物有广谱杀灭作用,对多数革兰氏阳性菌、革兰氏阴性菌、真菌以及囊膜病毒有强烈抑制作用。根据抗菌肽前体的基因结构、氨基酸序列特征，可将猪源抗菌肽分为4类：富含保守的胱氨酸防御素（Defensins）超家族、Cathelicidins家族、Cecropins家族和NK-lysin。防御素和Cathelicidin是到目前为止在哺乳动物中所发现的两个最大群体的抗菌肽家族其中猪小肠是生物活性小肽的重要富集区，分子量均在3kDa～10kDa之间。     

抗菌肽在猪病防治中的应用

抗菌肽作为一种具备较强抗真菌、抗病毒干扰能力的药剂,在猪病的防治过程中起非常重要的作用。提高生猪抵抗真菌、病毒等的免疫力,降低呼吸道感染等一系列疾病的概率,保障生猪的健康生长。该文分析了抗菌肽的作用,讨论和研究在生猪疾病防治中的应用。     

动物源性抗菌肽抗菌机理的研究进展

动物源性抗菌肽是动物体抵御外源性病原微生物入侵而产生的一类小分子多肽,与传统抗生素相比在抗菌方面有着独特的作用机理.本文综述了动物源性抗菌肽的一般特性、作用机理和影响抗菌活性和结构之间的关系,以期为抗菌肽的应用和开发提供必要的理论参考.     

抗菌肽的研究进展

抗菌肽是生物体防御系统中产生的一类对抗外源性病原体的肽物质。具有抗细菌、霉菌、病毒、原虫、癌细胞、螺旋体等多种活性，且不易产生耐药性，具有广阔的应用前景。作者从抗菌肽的分类、结构特征、作用机理、应用前景和存在的问题等方面进行阐述。     

抗菌肽的研究进展

抗菌肽是广泛存在于自然界生物中的具有广谱抗菌、抗病毒、抑制杀伤肿瘤细胞等作用的多肽。本文介绍了抗菌肽的结构,抗菌肽的生物学活性,抗菌肽的作用机理和作用机制,以及抗菌肽的应用和前景。     

抗菌肽Protegrins研究进展

抗菌肽广泛存在于自然界,是动物先天免疫的重要组成成分.Protegrins是其中一类由16～18个氨基酸构成的小肽.本文综述了Protegrins在结构、基因表达和调控、作用机理及生物学活性等方面的研究进展,并对其应用前景进行了展望.     

Tissue expression and developmental regulation of chicken cathelicidin antimicrobial peptides

ABSTRACT: Cathelicidins are a major family of antimicrobial peptides present in vertebrate animals with potent microbicidal and immunomodulatory activities. Four cathelicidins, namely fowlicidins 1 to 3 and cathelicidin B1, have been identified in chickens. As a first step to understand their role in early innate host defense of chickens, we examined the tissue and developmental expression patterns of all four cathelicidins. Real-time PCR revealed an abundant expression of four cathelicidins throughout the gastrointestinal, respiratory, and urogenital tracts as well as in all primary and secondary immune organs of chickens. Fowlicidins 1 to 3 exhibited a similar tissue expression pattern with the highest expression in the bone marrow and lung, while cathelicidin B1 was synthesized most abundantly in the bursa of Fabricius. Additionally, a tissue-specific regulatory pattern was evident for all four cathelicidins during the first 28 days after hatching. The expression of fowlicidins 1 to 3 showed an age-dependent increase both in the cecal tonsil and lung, whereas all four cathelicidins were peaked in the bursa on day 4 after hatching, with a gradual decline by day 28. An abrupt augmentation in the expression of fowlicidins 1 to 3 was also observed in the cecum on day 28, while the highest expression of cathelicidin B1 was seen in both the lung and cecal tonsil on day 14. Collectively, the presence of cathelicidins in a broad range of tissues and their largely enhanced expression during development are suggestive of their potential important role in early host defense and disease resistance of chickens.     

Tissue expression and developmental regulation of chicken cathelicidin antimicrobial peptides

Cathelicidins are a major family of antimicrobial peptides present in vertebrate animals with potent microbicidal and immunomodulatory activities. Four cathelicidins, namely fowlicidins 1 to 3 and cathelicidin B1, have been identified in chickens. As a first step to understand their role in early innate host defense of chickens, we examined the tissue and developmental expression patterns of all four cathelicidins. Real-time PCR revealed an abundant expression of four cathelicidins throughout the gastrointestinal, respiratory, and urogenital tracts as well as in all primary and secondary immune organs of chickens. Fowlicidins 1 to 3 exhibited a similar tissue expression pattern with the highest expression in the bone marrow and lung, while cathelicidin B1 was synthesized most abundantly in the bursa of Fabricius. Additionally, a tissue-specific regulatory pattern was evident for all four cathelicidins during the first 28 days after hatching. The expression of fowlicidins 1 to 3 showed an age-dependent increase both in the cecal tonsil and lung, whereas all four cathelicidins were peaked in the bursa on day 4 after hatching, with a gradual decline by day 28. An abrupt augmentation in the expression of fowlicidins 1 to 3 was also observed in the cecum on day 28, while the highest expression of cathelicidin B1 was seen in both the lung and cecal tonsil on day 14. Collectively, the presence of cathelicidins in a broad range of tissues and their largely enhanced expression during development are suggestive of their potential important role in early host defense and disease resistance of chickens.     

蚕类抗菌肽及其研究进展

抗菌活性肽被认为是从细菌到高等哺乳动物都普遍存在的一类防御性多肽。被称之为“第二防御体系”，具有抗细菌、真菌、病毒、原虫及抑癌活性，有潜在的应用价值。近年来。对抗菌肽的研充已成为一个迅速发展的新领域，越来越引起人们的关注和重视。本介绍蚕类抗菌肽的种类、作用机理、生物活性、抗菌肽基因的分子设计、克隆与表达以及抗菌肽在转基因动植物方面的研究状况。并探讨了抗菌肽的应用前景及存在的问题。     

猪血液同工酶遗传多态性的研究应用进展

血液同工酶遗传多态性属于生化遗传标记的范畴，通过标记辅助选择，实现早期选种。综述了LDH同工酶、AKP同工酶、ES同工酶、AMY同工酶四种血液同工酶遗传多态性的研究进展及其在猪遗传育种中的应用，旨在为猪遗传育种工作者提供一些理论资料，并探讨了该领域今后的研究方向。     

抗菌肽的研究进展

抗菌肽(antibacterical peptides)是存在于生物体内、具有抵抗外界微生物侵害、消除体内突变细胞的一类小分子多肽[1],是由细菌特定基因编     

牛蛙(Rana catesbeiana)蛙皮抗菌肽基因的克隆、测序及其表达

利用RT—PCR的方法从牛蛙皮肤组织中克隆到大小为270bp的片段RCABP，将其克隆到pGEM—T载体，测序获得1个新的碱基序列。将此基因克隆到原核表达载体pQE一80L，获得融合表达质粒pQE一80L／DHFR／ABP，在1％IPTG诱导下进行表达。SDS—PAGE检测表明，重组蛙皮抗菌肽蛋白的表达量占菌体总蛋白的24％，以包涵体形式存在。体外抑菌试验表明，所构建的质粒能在大肠杆菌中表达具有体外抑菌活性的蛙皮抗菌肽，该融合蛋白具有良好的应用前景。     

Antimicrobial activity of cathelicidins BMAP28, SMAP28, SMAP29, and PMAP23 against Pasteurella multocida is more broad-spectrum than host species specific

The antimicrobial activity of linear, cationic alpha-helical peptides from cattle (BMAP28), sheep (SMAP28 and SMAP29), and pigs (PMAP23) were assessed to determine if activity was selective for Pasteurella multocida from a particular animal species or broad-spectrum against all P. multocida tested. The antimicrobial activities of synthetic peptides were determined for P. multocida isolated from cattle (10 isolates), sheep (10 isolates), and pigs (10 isolates) in a broth microdilution assay. All thirty isolates of P. multocida were susceptible to BMAP28 (MICs and MBCs, 1.0-1.9 microM); SMAP28 and SMAP29 (MICs and MBCs, 0.2-0.7 microM); and PMAP23 (MICs and MBCs, 4.3 to > or = 6.8 microM). Overall, the results of this study suggest that synthesized cathelicidins from cattle, sheep, and pigs had broad-spectrum antimicrobial activity against all P. multocida.     

牛抗菌肽研究进展

抗菌肽（antibacteial peptides）又称抗微生物肽（antibacteial peptides）、多肽抗生素（peptide antibiotics），氨基酸数目小于100,常带正电荷，是生物体内产生的一类具有强抗菌作用的阳离子多肽，是生物先天免疫的重要组成成分。