Peroxyoxalate chemiluminescence enhanced by oligophenylenevinylene fluorophores in the presence of various surfactants

The effect of several surfactants on peroxyoxalate chemiluminescence (PO‐CL) using oligophenylenevinylene fluorophores was investigated. Among several oligophenylenevinylenes consisting of stilbene units, linearly conjugated ones, such as distyrylbenzene and distyrylstilbene, effectively enhanced PO‐CL efficiency. Various effects of anionic, cationic, amphoteric and non‐ionic surfactants on the CL efficiency of PO‐CL were determined using three oxalates and the distyrylbenzene fluorophore. Anionic and non‐ionic surfactants effectively enhanced CL efficiency, in contrast to the negative effect of cationic and amphoteric surfactants. Non‐ionic surfactants were also effective in CL reactions of oxalates bearing dodecyl ester groups by the hydrophobic interaction between their alkyl chains. Considering these results, the surfactants not only increase the concentrations of water‐insoluble interacting species in the hydrophobic micelle cores, but also control rapid degradation of the oxalates by alkaline hydrolysis. Copyright © 2014 John Wiley & Sons, Ltd.     

Interaction of bradykinin with sodium dodecyl sulfate and certain acidic lipids

The striking change in the circular dichroism (CD) of bradykinin (BK) occasioned by its interaction with sodium dodecyl sulfate (SDS) is evidently due in large part to a change in the conformation of the C-terminal tetrapeptide moiety of the hormone. The full change in CD is induced by the binding of two molecules of monomeric SDS per peptide molecule, the complex being aggregated. Formation of the 1:2 BK-SDS complex apparently proceeds via intermediates of stoichiometry 1:1 and 2:1. The cooperative nature of the interaction is attributed to the SDS-promoted aggregation of BK. Electrostatic interactions with the Arg residues appear important for the binding reaction per se. CD reveals that BK also interacts with acidic lipids which bear a net electrical charge (e.g., cerebroside sulfate and phosphatidyl inositol) but not with lipids bearing no net charge (e.g., cerebroside and phosphatidyl choline). The interactions are with particular mixed micelles of the lipid and the nonionic surfactant used for their solubilization, micellar size and structure being examined by surface tensiometry and electron microscopy.     

表面活性剂对嗜热脂肪芽孢杆菌产高温蛋白酶的影响

研究了表面活性剂对嗜热脂肪芽孢杆菌(Bacillusstearothermophilus)WF146产胞外高温蛋白酶的影响。结果表明,表面活性剂Tween80在0.05%～0.1%(体积比)浓度范围内对WF146产酶有一定的促进作用。在培养基中添加0.1%Tween80可使发酵液酶活提高12.7%,Tween20和TritonX100则抑制嗜热脂肪芽孢杆菌WF146产酶。另外,TritonX100抑制嗜热脂肪芽孢杆菌WF146生长,而Tween80和Tween20不抑制其生长。     

表面活性剂对林可霉素发酵生产的影响

在林可霉素发酵过程中,当向培养基中加入表面活性剂十二烷基磺酸钠(SDS)、吐温80(Tween 80)和曲拉通(Triton X-100)时,林可霉素的产量受到较大影响。本研究应用响应面设计法(Response surface design)对表面活性剂的配比进行了优化,得到的优化配比为:十二烷基磺酸钠为31.13 mg/100 mL,吐温80为51.97 mg/100 mL,曲拉通为16.9 mg/100 mL。将该优化配比应用于林可霉素发酵,产量提高了36.67%。     

Assessment of the effect of triton X‐114 on the physicochemical properties of an antibody fragment

The effect of Triton X‐114 on the physicochemical properties of a single‐chain antibody fragment (scFv) has been studied. According to the far UV circular dichroism spectroscopy, the secondary structure of the recombinant antibody was not significantly affected by the presence of Triton. From the antibody tertiary structure analysis, it was found that the surfactant could be located around the tryptophan molecules accessible to the solvent, diminishing the polarity of its environment but maintaining most of the protein structure integrity. However, in certain conditions of high temperature and high concentration of denaturant molecules, the presence of TX could compromise the antibody fragment stability. These results represent a previous step in designing scFv purification protocols and should be considered prior to developing scFv liquid–liquid extraction procedures. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 30:554–561, 2014     

表面活性剂对嗜盐嗜碱硫碱弧菌D301生成及利用硫颗粒的影响

【背景】微生物脱硫是脱除气体中硫化氢的一种有效方法,其中,硫颗粒的生成与代谢是控制生物脱硫效率的关键,但目前相应的控制方法很少。【目的】研究不同种类表面活性剂对硫碱弧菌D301生成及利用硫颗粒的影响。【方法】通过摇床培养,利用X射线衍射、冷场发射扫描电镜、能谱分析及傅里叶红外光谱对硫颗粒进行表征。【结果】单质硫主要以S8形式存在,吐温-80和十二烷基磺酸钠(Sodium Dodecyl Sulfate,SDS)的添加对硫颗粒的形态及生成量影响明显。对照组中生成的硫颗粒呈规则球形,光滑完整,其表面附着蛋白质等生物大分子;加入0.01 g/L吐温-80后,硫颗粒呈长杆状、颗粒增大、利用速率减慢;加入0.3g/L的SDS后,硫颗粒呈短棒状、生成量减少、利用速率加快,同时延缓了硫碱弧菌D301的衰亡。【结论】添加表面活性剂可以改变硫颗粒形态并且影响其利用,是一种调控硫颗粒生成和代谢的有效手段。     

Serum biomarkers in interstitial lung diseases

The use of biomarkers in medicine lies in their ability to detect disease and support diagnostic and therapeutic decisions. New research and novel understanding of the molecular basis of the disease reveals an abundance of exciting new biomarkers who present a promise for use in the everyday clinical practice. The past fifteen years have seen the emergence of numerous clinical applications of several new molecules as biologic markers in the research field relevant to interstitial lung diseases (translational research). The scope of this review is to summarize the current state of knowledge about serum biomarkers in interstitial lung diseases and their potential value as prognostic and diagnostic tools and present some of the future perspectives and challenges.     

表面活性剂对木质纤维素酶解产糖的影响研究进展

木质纤维素是生产生物燃料乙醇的主要原料,其含量丰富、绿色环保以及可再生性,因此有效地利用木质纤维素有望解决能源短缺问题。表面活性剂能够有效地促进木质纤维素的酶解反应,通过探讨不同表面活性剂对酶解反应的影响及机理,为实际的酶解过程找到合适表面活性剂提供一定的理论指导。     

Mass Spectrometry and Machine Learning Reveal Determinants of Client Recognition by Antiamyloid Chaperones

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Lung surfactant in subacute pulmonary disease

Pulmonary surfactant is a surface active material composed of both lipids and proteins that is produced by alveolar type II pneumocytes. Abnormalities of surfactant in the immature lung or in the acutely inflamed mature lung are well described. However, in a variety of subacute diseases of the mature lung, abnormalities of lung surfactant may also be of importance. These diseases include chronic obstructive pulmonary disease, asthma, cystic fibrosis, interstitial lung disease, pneumonia, and alveolar proteinosis. Understanding of the mechanisms that disturb the lung surfactant system may lead to novel rational therapies for these diseases.