Tinea are superficial fungal infections caused by dermatophytes. Luliconazole exhibits highest antifungal activity against Trichophyton spp. which are major causative agents of dermatophytosis. However, luliconazole suffers from drawbacks such as less skin retention, low aqueous solubility and poor skin penetration. To overcome the limita

The emergence of Pseudomonas aeruginosa as a potential threat in persistent infections can be attributed to the plethora of virulence factors expressed by it. This review discusses the various virulence factors that help this pathogen to establish an infection and regulatory systems controlling these virulence factors. Cell-associated virulence factors such as flagella, type IV pili and non-pilus adhesins have been reviewed. Extracellular virulence factors have also been explained. Quorum-sensing systems present in P. aeruginosa play a cardinal role in regulating the expression of virulence factors. The identification of novel virulence factors in hypervirulent strains indicate that the expression of virulence is dynamic and constantly evolving. An understanding of this is critical for the better clinical management of infections.

A new strategy to prevent degradation of recombinant proteins caused by non-specific cleavage by thrombin is described. We demonstrate that degradation due to non-specific cleavage of recombinant protein mediated by thrombin can be completely prevented by separation of thrombin from the recombinant protein on spin columns packed with heparin-sepharose. This method is generally applicable to all recombinant proteins that require the thrombin for the cleavage of affinity tags for purification. To our knowledge, this is the first report of an efficient and reliable method for the separation of residual thrombin from purified recombinant proteins.Keywords recombinant protein; thrombin; heparin; degradation; structure; non-specific Large scale production and purification of pure recombinant proteins is the first important step towards understanding their structure-function relationship [1,2]. In general, recombinant proteins are bioengineered with affinity tag either at their N-or C-terminus [2]. These affinity tags not only facilitate easy purification of recombinant proteins, but are also known to aid in overexpression of proteins in soluble forms [3]. To eliminate downstream interference, many fusion vectors are designed such that the fusion partner (affinity tag) can be easily eliminated from the protein of interest after cell lysis. This is most often accomplished by the insertion of a protease-specific cleavage site between the affinity tag and the recombinant protein of interest [3]. Thrombin is one of the common and popular restriction proteases used for removal of affinity tags from recombinant fusion proteins [4,5]. It is preferred to other restriction proteases due to its relatively low cost and optimum cleavage activity in the pH range of 6-8. Thrombin, an endoprotease, is known to preferentially recognize the -Leu-Val-Pro-Arg-Gly-Sersequence and cleave at the Arg-Gly bond [6]. Despite its extensive use, thrombin has been reported to non-specifically cleave at secondary sites located in some overexpressed recombinant proteins [6]. Non-specific cleavage mediated by thrombin is quite common. However, to date there is no efficient experimental procedure to prevent the undesired nonspecific cleavage of recombinant proteins caused by thrombin. Heterogeneous protein samples generated by non-specific thrombin catalyzed cleavage would pose a major hurdle for structural studies such as X-ray crystallography and NMR spectroscopy. In this study, we report a novel *To whom all correspondence should be addressed. Dr. Thallapuranam Krishnaswamy Suresh Kumar (Department of Chemistry & Biochemistry, University of Arkansas, Fayetteville, AR 72701). E-mail:sthalla@uark.edu, Fax: 479-575-5646, Phone: 479-575-4049. Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in...

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A carefully designed ammonium sulfate precipitation will simplify extraction of proteins and is considered to be a gold standard among various precipitation methods. Therefore, optimization of ammonium sulfate precipitation can be an important functional step in protein purification. The presence of high amounts of ammonium sulphate precludes direct detection of many enzymatically active proteins including reducing sugar assays (e.g. Nelson-Somogyi, Reissig and 3,5-dinitrosalicylic acid methods) for assessing carbohydrases (e.g. laminarinase (β (1–3)-glucanohydrolase), cellulases and chitinases). In this study, a simple method was developed using laminarin infused agarose plate for the direct analysis of the ammonium sulphate precipitates from Streptomyces rimosus AFM-1. The developed method is simple and convenient that can give accurate results even in presence of ammonium sulfate in the crude precipitates. Laminarin is a translucent substrate requiring the use of a stain to visualize the zones of hydrolysis in a plate assay. A very low-cost and locally available fluorescent optical fabric brightener Tinopal CBS-X has been used as a stain to detect the zones of hydrolysis. We also report simple methods to prepare colloidal chitin and cell free supernatant in this manuscript.