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1.
中国拥有丰富的两栖类动物资源,它是中国生物资源的重要组成部分,也是人类的宝贵财富,具有很大的开发利用潜力。中国对两栖类生物资源的开发利用已取得一定的成果,但还有很多不足,尤其是关于两栖类皮肤活性生物分子的研究开发工作,基本上还是一片空白。着眼于疾病治疗因子的筛选和生物活性分子的发现,对中国部分两栖类动物进行了系统的筛选研究。发现了一系列的生物活性分子和可能具临床应用价值的生物因子,并结合中国及世界两栖类资源开发利用的现状,主要从药物开发和资源保护的角度对中国两栖类资源的开发利用提出几点建议。  相似文献   

2.
山溪鲵皮肤分泌物抗菌活性的初步研究   总被引:5,自引:0,他引:5  
山溪鲵皮肤分泌物和经两次SephadexG-25层析分离得到的初步提纯样品经抗菌实验,发现具有抗菌活性。其中的抗菌活性成分为蛋白质性质,分子量约为20kD,具有在高温下短时间、常温下长时间保持稳定的特性。初步提纯样品经尿素SDS聚丙烯酰胺凝胶电泳检测为两条带;经反相高效液相层析(RP-HPLC)检测为13个峰。此提纯方法的活性回收率为46.7%。这为进一步的纯化和性质鉴定工作奠定了基础。  相似文献   

3.
具有生物活性的天然三萜化合物的研究进展   总被引:1,自引:0,他引:1       下载免费PDF全文
三萜类化合物是广泛存在于自然界的一类有机化合物,其中很多具有一定的生物活性。该文着重综述了近五年来具有抗炎、抗菌、抗肿瘤生物活性的天然游离三萜化合物的研究进展。  相似文献   

4.
张云 《动物学研究》2006,27(1):101-112
以大蹼铃蟾(Bombina maxima)为代表性物种,揭示了两栖类皮肤分泌物蛋白质多肽组丰富的分子和功能多样性。目前在大蹼铃蟾已发现的分子包括3类不同的抗菌肽、缓激肽、缓激肽增强肽和缓激肽拮抗肽、缓激肽基因相关肽、富含脯氨酸铃蟾肽及其基因相关肽、神经调节素U、Bv8肽、三叶型蛋白和蛋白酶抑制剂等。抗菌肽分子多样性及其形成机制、缓激肽及其基因相关肽功能和表达模式的多样性都较好地揭示了在多样的生态条件下,两栖类皮肤活性肽环境适应的分子基础及生物合成的调控机制。富含血红素辅基的白蛋白广泛分布在大蹼铃蟾皮肤外皮层细胞膜上和真皮海绵层内,表明它在皮肤的生理功能,如在呼吸、物质交换和渗透压调节中有重要作用。两栖类皮肤分泌物蛋白质多肽组,由于其分子结构的多样性、新颖性和哺乳类同系物的存在,在生物医学研究和天然药物开发中具有独特和不可替代的价值;同时,两栖类皮肤功能基因组具有多样性丰富、快速重组突变的特征,是探讨生物适应的基因基础、基因形成机制和进化特性等生物学基本问题的优秀模型。  相似文献   

5.
目的比较三种临床常用妇科栓剂保妇康、消糜栓、复方莪术油栓治疗大鼠宫颈糜烂模型的作用和抗菌活性。方法50只大鼠分为空白对照组、模型组、保妇康、消糜栓、复方莪术油栓组,以阴道注入苯酚胶浆造成宫颈糜烂模型,空白对照仅给予生理盐水,药物治疗7d后,观察宫颈的组织病理切片。采用琼脂稀释法测定最小抑菌浓度以比较三种药物对大肠杆菌、金黄色葡萄球菌、白色念珠菌的抑制活性。结果与对照相比,模型组表现明显的宫颈糜烂,大量炎细胞浸润、血管扩张充血及阴道上皮角化,而三种药物对大鼠宫颈糜烂均有明显的治疗作用,其中复方莪术油栓的效果最为明显,复方莪术油栓显著抑制金黄色葡萄球菌和白色念珠菌,但对大肠杆菌抑制作用不明显,保妇康、消糜栓也具有一定的抗菌活性。结论三种药物对大鼠宫颈糜烂均有明显的治疗作用和抗菌活性,其中复方莪术油栓的效果较为明显,为临床用药提供了参考。  相似文献   

6.
黄酮的结构改造与生物活性   总被引:7,自引:0,他引:7  
黄酮是一类重要的天然有机化合物,属于黄酮类化合物的一个亚类,具有广泛的生理活性,如抗肿瘤,抗炎,抗菌等.本文以化学修饰的黄酮衍生物为例,综述了具有抗多药耐药、抗肿瘤、抗菌等活性的黄酮衍生物结构与活性的关系.  相似文献   

7.
两栖动物皮肤结构及皮肤抗菌肽   总被引:13,自引:2,他引:13       下载免费PDF全文
两栖动物皮肤在自然进化过程中形成了防御病原微生物的三套防御系统,相应地具有特定结构。皮肤抗菌肽是其中先天性防御系统的主要组成部分。本文概述了两栖动物皮肤结构特点以及皮肤抗菌肽在国内外的最新研究进展,重点介绍了两栖动物皮肤腺体和蛙皮抗菌肽的种类、分子结构、抗菌机理、基因表达调控及cDNA编码特点以及基因工程等。以期系统认识和了解这些方面的研究与进展。  相似文献   

8.
Wang A  Wang J  Hong J  Feng H  Yang H  Yu X  Ma Y  Lai R 《Biochimie》2008,90(6):863-867
While conducting experiments to investigate antimicrobial peptides of amphibians living in the Yunnan-Sichuan region of southwest China, a new family of antimicrobial peptides was identified from skin secretions of the rufous-spotted torrent frog, Amolops loloensis. Members of the new peptide family named amolopins are composed of 18 amino acids with a unique sequence, for example, NILSSIVNGINRALSFFG. By BLAST search, amolopins did no show similarity to any known peptides. Among the tested microorganisms, native and synthetic peptides only showed antimicrobial activities against Staphylococcus aureus ATCC2592 and Bacillus pumilus, no effects on other microorganisms. The CD spectroscopy showed that it adopted a structure of random combined with beta-sheet in water, Tris-HCl or Tris-HCl-SDS. Several cDNAs encoding amolopins were cloned from the skin cDNA library of A. loloensis. The precursors of amolopin are composed of 62 amino acid residues including predicted signal peptides, acidic propieces, and mature antimicrobial peptides. The preproregion of amolopin precursor comprises a hydrophobic signal peptide of 22 residues followed by an 18 residue acidic propiece which terminates by a typical prohormone processing signal Lys-Arg. The preproregions of precursors are very similar to other amphibian antimicrobial peptide precursors but the mature amolopins are different from other antimicrobial peptide families. The remarkable similarity of preproregions of precursors that give rise to very different antimicrobial peptides in distantly related frog species suggests that the corresponding genes form a multigene family originating from a common ancestor.  相似文献   

9.
    
Antimicrobial peptides are widely distributed in nature and appear to play important roles in the host defense of plants and animals. In this study, we isolated and characterized three antimicrobial peptides from skin secretions of the oriental fire‐bellied toad, Bombina orientalis. These purified peptides were referred to as P1, P2, and P3 in order of their elution. P1, P2, and P3 have molecular weights of 2569, 2566, and 2370 Da by MALDI‐TOF mass spectrometer, respectively. They are heat‐stable, amphipathic peptides of 24–27 amino acids without cysteine residues. All three peptides are active against representative gram negative and gram positive bacterial species, and in particular, P1 appears to have distinctive antifungal activity. However, no significant hemolytic activity was found for these peptides  相似文献   

10.
The secretions of the mandibular and metapleural glands of leaf cutting ants contain antimicrobial substances that protect the mutualistic fungal colony within the nest from attack by parasitic micro-organisms. The major constituents of these secretions (citral, 4-methyl-3-heptanol, 2-heptanone, 3-octanone, 4-methyl-2-heptanone, β-citronellol, geraniol, phenylacetic, indolacetic, hexanoic and octanoic acids were tested against resistant strains of the human pathogens, Escherichia coli, Staphylococcus aureus and Candida albicans. Assays were carried out using filter paper discs impregnated with either hexane or water solutions of the analytes in the concentration range 250–6,000 ng/μl. Although most of the tested compounds presented strong antibacterial and antifungal activities, citral, geraniol, 4-methyl-3-heptanol, hexanoic and octanoic acids were the most effective, particularly against C. albicans. The results suggest that these compounds may be of potential value as antibiotics in the treatment of human candidiasis.  相似文献   

11.
天然抗菌肽的研究进展及应用前景   总被引:2,自引:1,他引:2  
天然抗菌肽是生物体内经诱导产生的一种具有抗菌活性的小分子多肽,来源广泛。目前已从多种物种中分离纯化出千余种抗菌肽,其分子量大约在3~6kD之间,由20~60个氨基酸残基组成。天然抗菌肽具有多种生物活性,如抗细菌、抗真菌、抗病毒和抗癌细胞等作用。综述了天然抗菌肽的分类、生物活性及其作用机理和应用前景。  相似文献   

12.
王妍  周江  王义鹏  肖宁 《动物学杂志》2021,56(2):303-319
两栖类动物皮肤裸露和湿润的特性易于微生物的生长,它们为了抵御病原微生物的侵袭,在长期自然进化过程中形成了以抗菌肽(AMPs)为主要防御机制的免疫系统。抗菌肽广泛分布于动物、植物、微生物中,是生物用于抵御细菌、真菌、病毒和原虫等病原体侵袭的重要武器之一,在进化上是一类非常古老而有效的天然防御物质。Cathelicidins是脊椎动物特有的重要抗菌肽家族之一,除具有高效广谱的抗菌活性,还具有如抗炎、抗氧化、伤口修复、抑制组织损伤和促进血管生成等多种重要活性,因此Cathelicidins家族抗菌肽已成为抗感染多肽类新药的研发热点。本文将从两栖类动物Cathelicidins家族抗菌肽的一般特点、来源分布、生物合成与结构、生物学活性、作用机制及应用前景等几个方面,综合阐述国内外的研究动态。  相似文献   

13.
两栖类皮肤抗菌多肽及其应用   总被引:6,自引:0,他引:6  
赖仞  粱建国  张云 《动物学研究》2004,25(5):465-468
抗菌多肽广泛分布于动物、植物,用于抵御细菌、真菌、病毒和原虫,在进化上是一类非常古老而有效的天然防御物质。两栖动物的后天获得性免疫系统与哺乳动物相比极为脆弱,它们在长期的进化历程中演化形成了一套非常有效的抵御微生物侵袭的防御系统,这套系统主要就是其裸露皮肤表面的抗菌多肽(又称初级免疫或者先天免疫系统)。本文结合本实验室近年的研究工作,对两栖类皮肤抗菌多肽的结构、功能及应用作一简要综述。  相似文献   

14.
芽孢杆菌(Bacillus spp.)作为生防细菌,已广泛应用于农作物、畜、禽、水产动物的病害防控,也是当今微生物生态防控的研究热点.贝莱斯芽孢杆菌(Bacillus velezensis)是芽孢杆菌属的一个新种,因其能够产生多种次级代谢产物,并且具有广谱抑菌活性和促生长作用,被广泛应用于动植物病害的生物防治.本文从贝...  相似文献   

15.
    
As a group of intestinal hormones and neurotransmitters, cholecystokinins(CCKs) regulate and affect pancreatic enzyme secretion, gastrointestinal motility, pain hypersensitivity, digestion and satiety, and generally contain a DYMGWMDFG sequence at the C-terminus. Many CCKs have been reported in mammals. However, only a few have been reported in amphibians, such as Hyla nigrovittata, Xenopus laevis, and Rana catesbeiana, with none reported in urodele amphibians like newts and salamanders. Here, a CCK called CCK-TV was identified and characterized from the skin of the salamander Tylototriton verrucosus. This CCK contained an amino acid sequence of DYMGWMDF-NH2 as seen in other CCKs. A c DNA encoding the CCK precursor containing 129 amino acid residues was cloned from the c DNA library of T. verrucosus skin. The CCK-TV had the potential to induce the contraction of smooth muscle strips isolated from porcine gallbladder, eliciting contraction at a concentration of 5.0x10-11 mol/L and inducing maximal contraction at a concentration of 2.0x10-6 mol/L. The EC50 was 13.6 nmol/L. To the best of our knowledge, this is the first report to identify the presence of a CCK in an urodele amphibian.  相似文献   

16.
More than ten bradykinin-related peptides and their cDNAs have been identified from amphibians, but their genes are unknown. In present study, four cDNAs encoding one, two, four and six copies of bradykinin-related peptides were cloned from the frog (Odorrana grahami) skin cDNA library, respectively. Three bradykinin-related peptides (bradykinin, Thr6-bradykinin, Leu5Thr6-bradykinin) were deduced from these four cDNA sequences. Based on the cDNA sequence, the gene sequence encoding an amphibian bradykinin-related peptide from O. grahami was determined. It is composed of 7481 base pairs including two exons and two introns. The first exon codes signal peptide and the second exon codes acidic spacer peptide and Thr6-bradykinin. The promoter region of the bradykinin gene contains several putative recognition sites for nuclear factors, such as SRY, GATA-1, LYF-1, DeltaE, CDXA, NKX-2.5, MIF1 and S8. The current work may facilitate to understand the regulation and possible functions of amphibian skin bradykinin-related peptides.  相似文献   

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