BACKGROUND & AIMS: :We compared the in vitro activities of tigecycline to those of other agents against 300 nonduplicate isolates of Streptococcus pneumoniae (194 isolates), Haemophilus influenzae (60 isolates), and Moraxella catarrhalis (46 isolates) recovered from patients treated in three major hospitals in Taiwan from August through December, 2003. All of these isolates were inhibited at 0.5 mg/L of tigecycline. For S. pneumoniae isolates, 72% were not susceptible to penicillin (69% intermediate and 3% resistant) and 96% were not susceptible to azithromycin. Among the 178 isolates resistant to azithromycin, 53 isolates (30%) had the M phenotype and 70% had the cMLSB phenotype. The rate of nonsusceptibility to ertapenem, telithromycin, moxifloxacin, and quinupristindalfopristin in S. pneumoniae was 3%, 2%, 1%, and 57%, respectively. For H. influenzae, 36 (60%) were not susceptible to ampicillin, among which 31 possessed beta-lactamase. A high rate (8.3%) of H. influenzae isolates with beta-lactamase-negative and ampicillin-resistant phenotype was found. All H. influenzae isolates were susceptible to azithromycin, but 40% of them were not susceptible to clarithromycin. Ninety-eight percent (44 isolates) of M. catarrhalis possessed beta-lactamase. All three fluoroquinolones tested were highly active (MIC90 < or =0.12 mg/L) against H. influenzae and M. catarrhalis.

背景与目标： : 我们比较了替加环素与其他药物对300种非重复肺炎链球菌分离株 (194株)，流感嗜血杆菌 (60株) 和卡他莫拉菌 (46株) 的体外活性，这些分离株是从8月到2003年12月在台湾的三家主要医院中康复的。在0.5 mg/L替加环素的浓度下，所有这些分离株均被抑制。对于肺炎链球菌分离株，72% 对青霉素不敏感 (69% 中间体和3% 耐药)，96% 对阿奇霉素不敏感。在对阿奇霉素耐药的178株中，53株 (30% 株) 具有M表型，70% 株具有cMLSB表型。肺炎链球菌对厄他培南，泰利霉素，莫西沙星和奎奴普汀的不敏感性分别为3%，2%，1% 和57%。对于流感嗜血杆菌，36 (60%) 对氨苄青霉素不敏感，其中31具有 β-内酰胺酶。发现具有 β-内酰胺酶阴性和氨苄青霉素抗性表型的流感嗜血杆菌分离株率高 (8.3%)。所有流感嗜血杆菌分离株对阿奇霉素敏感，但其中40% 对克拉霉素不敏感。卡他氏杆菌的百分之九十八 (44个分离株) 具有 β-内酰胺酶。测试的所有三种氟喹诺酮类药物对流感嗜血杆菌和卡他氏杆菌具有高度活性 (MIC90 <或 = 0.12 mg/L)。

BACKGROUND & AIMS: :Aurelin is a 40-residue cationic antimicrobial peptide isolated from the mezoglea of a scyphoid jellyfish Aurelia aurita. Aurelin and its (15)N-labeled analogue were overexpressed in Escherichia coli and purified. Antimicrobial activity of the recombinant peptide was examined, and its spatial structure was studied by NMR spectroscopy. Aurelin represents a compact globule, enclosing one 3(10)-helix and two α-helical regions cross-linked by three disulfide bonds. The peptide binds to anionic lipid (POPC/DOPG, 3:1) vesicles even at physiological salt concentration, it does not interact with zwitterionic (POPC) vesicles and interacts with the DPC micelle surface with moderate affinity via two α-helical regions. Although aurelin shows structural homology to the BgK and ShK toxins of sea anemones, its surface does not possess the "functional dyad" required for the high-affinity interaction with the K(+)-channels. The obtained data permit to correlate the modest antibacterial properties and membrane activity of aurelin.

背景与目标： : Aurelin是从scyphoid水母Aurelia aurita的mezoglea中分离出的40残基阳离子抗菌肽。Aurelin及其 (15)N标记的类似物在大肠杆菌中过表达并纯化。研究了重组肽的抗菌活性，并通过NMR光谱研究了其空间结构。Aurelin代表紧凑的小球，包含一个3(10)-螺旋和两个由三个二硫键交联的 α-螺旋区域。该肽即使在生理盐浓度下也与阴离子脂质 (POPC/DOPG，3:1) 囊泡结合，它不与两性离子 (POPC) 囊泡相互作用，并且通过两个 α 螺旋区域以中等亲和力与DPC胶束表面相互作用。尽管aurelin显示出与海葵的BgK和ShK毒素的结构同源性，但其表面不具有与K ()-通道高亲和力相互作用所需的 “功能性二体”。获得的数据允许将aurelin的适度抗菌特性和膜活性相关联。

BACKGROUND & AIMS: BACKGROUND:An effective screening tool for colorectal cancer is still lacking. Analysis of the volatile organic compounds (VOCs) linked to cancer is a new frontier in cancer screening, as tumour growth involves several metabolic changes leading to the production of specific compounds that can be detected in exhaled breath. This study investigated whether patients with colorectal cancer have a specific VOC pattern compared with the healthy population. METHODS:Exhaled breath was collected in an inert bag (Tedlar(®) ) from patients with colorectal cancer and healthy controls (negative at colonoscopy), and processed offline by thermal-desorber gas chromatography-mass spectrometry to evaluate the VOC profile. During the trial phase VOCs of interest were identified and selected, and VOC patterns able to discriminate patients from controls were set up; in the validation phase their discriminant performance was tested on blinded samples. A probabilistic neural network (PNN) validated by the leave-one-out method was used to identify the pattern of VOCs that better discriminated between the two groups. RESULTS:Some 37 patients and 41 controls were included in the trial phase. Application of a PNN to a pattern of 15 compounds showed a discriminant performance with a sensitivity of 86 per cent, a specificity of 83 per cent and an accuracy of 85 per cent (area under the receiver operating characteristic (ROC) curve 0·852). The accuracy of PNN analysis was confirmed in the validation phase on a further 25 subjects; the model correctly assigned 19 patients, giving an overall accuracy of 76 per cent. CONCLUSION:The pattern of VOCs in patients with colorectal cancer was different from that in healthy controls. The PNN in this study was able to discriminate patients with colorectal cancer with an accuracy of over 75 per cent. Breath VOC analysis appears to have potential clinical application in colorectal cancer screening, although further studies are required to confirm its reliability in heterogeneous clinical settings.

背景与目标：

BACKGROUND & AIMS: :Our view on the bacterial responses to the aerobic degradation of aromatic compounds has been enriched considerably by the current omic methodologies and systems biology approaches, revealing the participation of intricate metabolic and regulatory networks. New enzymes, transporters, and specific/global regulatory systems have been recently characterized, and reveal that the widespread biodegradation capabilities extend to unexpected substrates such as lignin. A completely different biochemical strategy based on the formation of aryl-CoA epoxide intermediates has been unraveled for aerobic hybrid pathways, such as those involved in benzoate and phenylacetate degradation. Aromatic degradation pathways are also an important source of metabolic exchange factors and, therefore, they play a previously unrecognized biological role in cell-to-cell communication. Beyond the native bacterial biodegradation capabilities, pathway evolution as well as computational and synthetic biology approaches are emerging as powerful tools to design novel strain-specific pathways for degradation of xenobiotic compounds.

背景与目标： : 当前的omic方法和系统生物学方法极大地丰富了我们对细菌对芳香族化合物需氧降解的反应的观点，揭示了复杂的代谢和调节网络的参与。最近已经表征了新的酶，转运蛋白和特定/全球调节系统，并揭示了广泛的生物降解能力扩展到意想不到的底物，例如木质素。基于芳基-CoA环氧化物中间体形成的完全不同的生化策略已针对好氧杂化途径 (例如涉及苯甲酸酯和乙酸苯酯降解的途径) 展开。芳香降解途径也是代谢交换因子的重要来源，因此，它们在细胞间通讯中起着以前未被认识的生物学作用。除了天然细菌的生物降解能力外，途径的进化以及计算和合成生物学方法正在成为设计新的菌株特异性途径以降解异种生物化合物的强大工具。

BACKGROUND & AIMS: :Twenty-four antimicrobial drugs were examined for rapidity of onset and magnitude of bactericidal activity against selected strains of Clostridium perfringens. Ceftriaxone, imipenem, metronidazole, mezlocillin, penicillin G, piperacillin, and teicoplanin reduced colony counts by at least 3 log10 units within 2-4 h after exposure. Clindamycin, fluoroquinolones, josamycin, and tetracycline caused delayed kill (greater than or equal to 99.9% reduction of viable counts at 4-22 h after exposure). Chloramphenicol and rifampin lacked bactericidal activity against 2 of 4 strains, whereas erythromycin, fusidic acid, and fosfomycin (with added glucose-6-phosphate) were merely inhibitory for all 4 strains. Imipenem and penicillin G were combined with 9 and 12 antimicrobial drugs, respectively. Essentially all drug combinations yielded indifferent effects; only penicillin G plus doxycycline resulted in an antagonistic effect against C. perfringens.

背景与目标： : 检查了24种抗菌药物对选定的产气荚膜梭菌菌株的起效速度和杀菌活性。头孢曲松，亚胺培南，甲硝唑，美洛西林，青霉素g，哌拉西林和替考拉宁在暴露后2-4小时内将菌落计数减少至少3 log10单位。克林霉素，氟喹诺酮类，交沙霉素和四环素引起延迟杀伤 (暴露后4-22小时活菌计数大于或等于99.9% 减少)。氯霉素和利福平对4株菌株中的2株缺乏杀菌活性，而红霉素，夫西地酸和磷霉素 (添加了6-磷酸葡萄糖) 仅对所有4株菌株具有抑制作用。亚胺培南和青霉素g分别与9种和12种抗菌药物联合使用。基本上所有的药物组合都产生不同的效果; 只有青霉素g加强力霉素导致对产气荚膜炎的拮抗作用。

BACKGROUND & AIMS: AIMS:To evaluate the prevalence and antimicrobial resistance of Enterococcus species from chickens and pigs in Beijing and Shandong Province, China. METHODS AND RESULTS:Swab samples were collected from four farms in Beijing and two in Shandong Province in 2009 and tested for Enterococcus. Minimum inhibitory concentrations of antimicrobial agents were determined using broth microdilution or agar screening methods. A total of 453 Enterococcus isolates were recovered, belonging to six different Enterococcus species. All isolates were sensitive to vancomycin. Resistance to tetracycline (92.5%), amikacin (89.4%), erythromycin (72.8%) and rifampin (58.1%), and high-level streptomycin resistance (HLSR, 50.3%) were prevalent, while resistance to penicillins (7.9% to penicillin and 4.2% to ampicillin) was rare. The resistance rates to phenicols (chloramphenicol and florfenicol) and enrofloxacin, and high-level gentamicin resistance (HLGR) were approximately 30%. The vast majority of the Enterococcus isolates were classified as multidrug-resistant organisms. CONCLUSIONS:Resistance of Enterococcus sp. to most antimicrobials was more prevalent in China than in European or other Asian countries. SIGNIFICANCE AND IMPACT OF THE STUDY:Our findings reveal a high level of antimicrobial resistance in Enterococcus isolates from food animals in China and underline the need for prudent use of antibiotics in chicken and pig production to minimize the spread of antibiotic-resistant enterococci.

背景与目标：

BACKGROUND & AIMS: OBJECTIVES:The precise role for intraventricular (IVT) antimicrobials in combination with systemic antibiotics in management of cerebrospinal fluid (CSF) diversion device-associated infections is uncertain. We evaluated our current practice, comparing dual therapy against systemic antimicrobials alone. METHODS:All adult patients with at least two consecutive CSF isolates who were treated for CSF diversion device-related infection over a 5-year period (2005-2010) were identified retrospectively. Clinical and laboratory parameters, microbiology, surgical and antimicrobial management, and treatment outcomes were analysed. RESULTS:Forty-eight patients were identified - 25 received IVT and systemic antibiotics (group A), and 23 systemic antibiotics alone (group B). Clinical features were similar between groups, as were causative organisms. CSF leucocyte counts differed slightly (A > B, p = 0.067) but no laboratory parameters differed significantly. Infected devices were generally revised (A = 92%, B = 91%). Mean times to CSF sterilisation and normalisation of CSF microscopy were significantly shorter for group A (p < 0.05 and p < 0.005 respectively), as was duration of hospital stay (p < 0.002) and required length of systemic antimicrobial therapy (p < 0.001). CONCLUSIONS:Our findings indicate that IVT antibiotics enhance clinical and microbiological recovery and should therefore be considered for patients with CSF infection associated with a CSF diversion device. We recommend further evaluation of this approach in a prospective, randomised, controlled trial.

背景与目标：

BACKGROUND & AIMS: The present study was conducted to clarify the mechanism of toxicity of organic compounds using lipid model membranes (liposomes and planar lipid membranes). The compounds studied were trialkyltin and trialkyllead chlorides, dialkyltin dichlorides and some inorganic forms of those metals. Two different (anionic and cationic) detergents were also used in the experiments to change the surface properties of liposomes. As a measure of interaction between the compounds studied and model membranes were the release of liposome bound praseodymium and the change in stability of planar membranes under the influence of those compounds. On the basis of the results obtained it was postulated that the mechanism of interaction between tin- and leadorganics and model lipid membranes is a combination of different factors featuring interacting sides. The most important properties determining the behaviour of organic compounds in the interaction were lipophilicity and polarity of different parts of the organics and the steric arrangement they can take in the medium. On the other hand, the surface potential of the lipid bilayer and the environment of the lipid molecules, that play a significant role in the availability of the lipid bilayer to the organics, were important factors in the interaction.

背景与目标： 本研究旨在阐明使用脂质模型膜 (脂质体和平面脂质膜) 对有机化合物的毒性机理。研究的化合物是三烷基锡和三烷基氯化铅，二烷基锡二氯化物以及这些金属的某些无机形式。实验中还使用了两种不同的 (阴离子和阳离子) 洗涤剂来改变脂质体的表面性质。作为研究化合物与模型膜之间相互作用的量度，脂质体结合镨的释放以及在这些化合物的影响下平面膜的稳定性变化。根据获得的结果，推测锡和铅有机物与模型脂质膜之间的相互作用机理是具有相互作用方面的不同因素的组合。决定有机化合物在相互作用中的行为的最重要特性是有机物不同部分的亲脂性和极性以及它们在介质中可以采用的空间排列。另一方面，脂质双层的表面电势和脂质分子的环境在脂质双层对有机物的可用性中起着重要作用，是相互作用的重要因素。

BACKGROUND & AIMS: :A novel and functional conjugative transfer system identified in O119:H2 enteropathogenic Escherichia coli (EPEC) strain MB80 by subtractive hybridization is encoded on a large multidrug resistance plasmid, distinct from the well-described EPEC adherence factor (EAF) plasmid. Variants of the MB80 conjugative resistance plasmid were identified in other EPEC strains, including the prototypical O111:NM strain B171, from which the EAF plasmid has been sequenced. This separate large plasmid and the selective advantage that it confers in the antibiotic era have been overlooked because it comigrates with the virulence plasmid on conventional gels.

背景与目标： : 通过消减杂交在O119:H2肠致病性大肠杆菌 (EPEC) 菌株MB80中鉴定出的新颖且功能强大的共轭转移系统被编码在大型多药耐药质粒上，与描述明确的EPEC粘附因子 (EAF) 质粒不同。在其他EPEC菌株中鉴定了MB80共轭抗性质粒的变体，包括原型O111:NM菌株B171，从中对EAF质粒进行了测序。这种单独的大质粒及其在抗生素时代赋予的选择性优势被忽略了，因为它与常规凝胶上的毒力质粒共同存在。

BACKGROUND & AIMS: :Chemical genetics employs diverse small-molecule compounds to elucidate biological processes in a manner analogous to the mutagenesis strategies at the core of classical genetics. Screening small-molecule libraries for compounds that induce a phenotype of interest represents the forward chemical genetic approach, whereas the reverse approach involves small molecules targeting a single protein. Here, we review key differences between the goals for small-molecule screening in industry versus academia, recent developments in high-throughput screening, and publicly available resources of compound collections, screening facilities, and databases. A particularly exciting outcome of a chemical genetic screen is the discovery of a previously unknown role for a protein in a pathway together with compounds that affect the function of that protein. In illustrative cases, such discoveries have led to progress toward therapeutic development and more commonly have increased the size of the small molecule "toolbox" available to the research community for the study of biological processes.

背景与目标： : 化学遗传学采用多种小分子化合物来阐明生物学过程，其方式类似于经典遗传学核心的诱变策略。筛选诱导感兴趣表型的化合物的小分子文库代表了正向化学遗传方法，而反向方法涉及靶向单个蛋白质的小分子。在这里，我们回顾了工业界与学术界小分子筛选的目标，高通量筛选的最新发展以及化合物集合，筛选设施和数据库的公开资源之间的主要差异。化学遗传筛选的一个特别令人兴奋的结果是发现了一种蛋白质在途径中的先前未知的作用以及影响该蛋白质功能的化合物。在说明性的情况下，这样的发现导致了治疗发展的进展，并且更常见的是增加了供研究界用于研究生物过程的小分子 “工具箱” 的大小。

BACKGROUND & AIMS: :Synthetic peptides, peptides A (Arg-Leu-Tyr-Leu-Arg-Ile-Gly-Arg-Arg-NH(2)) and B (Arg-Leu-Arg-Leu-Arg-Ile-Gly-Arg-Arg-NH(2)), derived from the beetle Allomyrina dichotoma defensin, have antimicrobial activities. Immunotoxicological effect of these peptides was evaluated by cytotoxicity of mouse peritoneal macrophages. In addition, antigenicity of these peptides was studied by evaluating antibody responses in mice immunized with these peptides. The toxicity of peptide A toward mouse peritoneal cells was less than that of polymyxin B, when morphologically evaluated in a cytotoxicity test. Almost all of mice injected intraperitoneally (i.p.) with either peptide A or B at 50-150 mg/kg survived, whereas all mice injected i.p. with polymyxin B at the doses of more than 25 mg/kg died within 24 h. Interestingly, almost all of mice injected intravenously with these peptides at the doses of 10 and 25 mg/kg also survived. Furthermore, mice immunized with these peptides conjugated with keyhole limpet hemocyanin (KLH) showed little or negligible anti-peptide A or B antibody production, although anti-KLH antibody was significantly produced. The results indicated that peptides A and B were less cytotoxic than polymyxin B and also had poor antigenicity to produce specific antibody in mice.

背景与目标： : 合成肽，肽A (Arg-Leu-Tyr-Leu-Arg-Ile-Gly-Arg-NH(2)) 和B (Arg-Leu-Arg-leg-Arg-Ile-Gly-Arg-NH(2))，衍生自甲虫二分蛋白防御素，具有抗菌活性。通过小鼠腹膜巨噬细胞的细胞毒性评估了这些肽的免疫毒理学作用。此外，通过评估用这些肽免疫的小鼠中的抗体反应，研究了这些肽的抗原性。在细胞毒性测试中进行形态学评估时，肽A对小鼠腹膜细胞的毒性小于多粘菌素B。几乎所有以50-150 mg/kg腹膜内 (i.p.) 注射肽A或B的小鼠均存活，而所有注射i.p.的小鼠均存活。多粘菌素b的剂量超过25 mg/kg，在24小时内死亡。有趣的是，几乎所有以10和25 mg/kg剂量静脉注射这些肽的小鼠也都存活了。此外，用这些与锁孔血蓝蛋白 (KLH) 缀合的肽免疫的小鼠显示出很少或可忽略的抗肽A或B抗体产生，尽管显着产生了抗KLH抗体。结果表明，肽A和肽B的细胞毒性低于多粘菌素B，并且在小鼠中产生特异性抗体的抗原性也较差。

BACKGROUND & AIMS: OBJECTIVE:Comparison of studies evaluating patient-to-patient transmission of organisms is difficult, given the lack of standardized criteria. We used fluoroquinolone-resistant Escherichia coli (FQREC) as a model to characterize variability in definitions of relatedness across studies and to evaluate the resultant impact on study conclusions. DESIGN:Narrative review and cohort study. METHODS:The narrative review compared relatedness criteria across studies of FQREC. Additionally, an existing database was used to compare relatedness of isolates on the basis of molecular criteria alone versus molecular plus clinical criteria with different temporal cutoffs (hospitalization overlap of ≥1 day or allowance for nonoverlap of hospitalization dates of ≤7 days or ≤30 days). RESULTS:Forty-six articles met narrative review inclusion criteria. Sixteen studies exclusively utilized molecular criteria to define relatedness. Thirty studies included molecular and clinical criteria. Of these, 6 included temporal data (ie, time period of isolate identification), 10 included patient location, and 14 included proximity and temporal criteria. For the database analysis, 353 patients were colonized with FQREC. There were 2 main clusters containing 48 and 17 related isolates within 49 pulsed-field gel electrophoresis types. Among the clusters, 18.4% of isolates were related by molecular criteria. Incorporating clinical criteria, fewer isolates were considered related: 5.7% of isolates using 30-day criteria, 3.1% using 7-day criteria, and 1.4% using 1-day overlap. CONCLUSIONS:There is considerable variability in definitions of relatedness of FQREC. Utilizing molecular criteria alone to define relatedness overestimates transmission compared with definitions including clinical criteria. Standard definitions of relatedness in studies of antimicrobial-resistant organisms are needed.

背景与目标：

BACKGROUND & AIMS: :In the present study we demonstrate the identification of phenolic compounds and the phenolic contents of the methanol extracts from stem and buds of Calligonum polygonoides with antioxidant activity. Eleven and nine phenolic compounds were identified and quantified from stem and buds, respectively by high-performance liquid chromatography (HPLC). p-Coumaric acid was predominant in stem and gallic acid in buds. In general, the samples with the highest phenolic contents had the highest antioxidant activities. Stem and buds sparked attention due to their high phenolic contents and antioxidant activities. The Results from present study reveal that the C. polygonoides could be considered as a promising source of antioxidant phytochemicals.

背景与目标： : 在本研究中，我们证明了酚类化合物的鉴定以及具有抗氧化活性的caligonum polygonoides茎和芽中甲醇提取物的酚类含量。通过高效液相色谱 (HPLC) 分别从茎和芽中鉴定出11种和9种酚类化合物并对其进行定量。对香豆酸在茎中占主导地位，在芽中占主导地位。通常，酚类含量最高的样品具有最高的抗氧化活性。茎和芽由于其高酚类含量和抗氧化活性而引起了人们的关注。本研究的结果表明，多角藻可被认为是抗氧化剂植物化学物质的有希望的来源。

BACKGROUND & AIMS: :We recently reported the discovery of octahydropyrrolo[1,2-a]pyrazine A as a lead compound for an inhibitor of apoptosis proteins (IAP) antagonist. To develop IAP antagonists with favorable PK profiles, we designed novel tri-cyclic compounds, octahydro-1H-cyclopropa[4,5]pyrrolo[1,2-a]pyrazines 1 and 2 based on co-crystal structural analysis of A with cellular IAP-1 (cIAP-1). The additional cyclopropane moiety was used to block the predicted metabolic site of compound A without detriment to the binding affinity for cIAP. Compounds 1 and 2 were stereoselectively synthesized via intermediates 4a and 5b', which were obtained by Simmons-Smith cyclopropanation of ethylester 3a and silyl ether 3b'. Compounds 1 and 2 showed strong growth inhibition in MDA-MB-231 breast cancer cells and improved metabolic stability in comparison to A. Compound 2 exhibited significant in vivo PD effects to increase tumor necrosis factor-alpha mRNA in a dose dependent manner.

背景与目标： : 我们最近报道了八氢吡咯并 [1,2-a] 吡嗪A作为凋亡蛋白抑制剂 (IAP) 拮抗剂的领先化合物的发现。为了开发具有良好PK谱的IAP拮抗剂，我们设计了新的三环化合物，octahydro-1H-cyclopropa[4,5] 吡咯并 [1，2-a] 吡嗪1和2基于A与细胞IAP-1 (cIAP-1) 的共晶体结构分析。额外的环丙烷部分用于阻断化合物A的预测代谢位点，而不损害对cIAP的结合亲和力。化合物1和2通过中间体4a和5b' 立体选择性合成，它们是通过乙酸酯3a和甲硅烷基醚3b' 的Simmons-Smith环丙烷化获得的。与A相比，化合物1和2在MDA-MB-231乳腺癌细胞中显示出强烈的生长抑制作用，并改善了代谢稳定性。化合物2表现出显著的体内PD效应，以剂量依赖性方式增加肿瘤坏死因子-α mRNA。

BACKGROUND & AIMS: :Amphibian skin secretions are known to contain numerous peptides with a large array of biological activities. Bombinins are a group of amphibian-derived peptides with broad spectrum antimicrobial activities that have been only identified from the ancient toad species, Bombina. In this study, we described the identification and characterization of a novel bombinin precursor which encoded a bombinin-like peptide (BLP-7) and a novel bombinin H-type peptide (named as Bombinin H-BO) from the skin secretion of Oriental fire-bellied toad, Bombina orientalis. The primary structures of both mature peptides were determined by combinations of molecular cloning of peptide precursor-encoding cDNAs and mass spectrometry techniques. Secondary structure prediction revealed that both peptides had cationic amphipathic α-helical structural features. The synthetic replicate of BLP-7 displayed more potent antimicrobial activity than Bombinin H-BO against Gram-positive and Gram-negative bacteria and yeast. Also, in vitro antitumour assay showed that both peptides possessed obvious antiproliferative activity on three human hepatoma cells (Hep G2/SK-HEP-1/Huh7) at the non-toxic doses. These results indicate the peptide family of bombinins could be a potential source of drug candidates for anti-infection and anticancer therapy.

背景与目标： 已知两栖动物皮肤分泌物含有大量具有大量生物活性的肽。Bombinins是一组具有广谱抗菌活性的两栖动物衍生肽，仅从古代蟾蜍物种Bombina中鉴定出。在这项研究中，我们描述了一种新的bombinin前体的鉴定和表征，该前体编码了一种bombinin样肽 (BLP-7) 和一种新的bombinin H型肽 (称为Bombinin H-BO)，来自东方火腹蟾蜍的皮肤分泌物，东方Bombina。通过编码肽前体的cdna的分子克隆和质谱技术的组合确定了两种成熟肽的一级结构。二级结构预测表明，两种肽均具有阳离子两亲性 α-螺旋结构特征。BLP-7的合成复制比Bombinin H-BO对革兰氏阳性和革兰氏阴性细菌和酵母表现出更有效的抗菌活性。此外，体外抗肿瘤测定表明，两种肽在无毒剂量下对三种人肝癌细胞 (Hep G2/SK-HEP-1/Huh7) 具有明显的抗增殖活性。这些结果表明，bombinins的肽家族可能是抗感染和抗癌治疗的候选药物的潜在来源。