Recent Publications View all
- SourceAvailable from: Ayadi Malika[Show abstract] [Hide abstract]
ABSTRACT: The entire pectate lyase cDNA (Pel1) of Penicillium occitanis was cloned from a cDNA bank and sequenced. The ORF exhibited a great homology to Penicillium marneffei and conservation of all features of fungal pectate lyases such as the barrel structure with "eight right-handed parallel β-helix" architecture. The structure modelling also showed the interesting resemblance with thermostable pectate lyases since several specific residues were also shared by Pel1 and these thermostable enzymes. Having shown that the enzyme retains its activity after EndoH-mediated deglycosylation, we investigated its expression in Escherichia coli BL21 using the pET28-a vector. This expression was shown to be optimum when cells were induced at room temperature in 2YT medium rather than at 37°C and LB medium. In such conditions, the recombinant protein was apparently produced more in soluble form than as inclusion bodies. The effect of NaCl concentration was investigated during the binding and elution steps of recombinant His-tagged enzyme on MagneHis Ni-Particles. The purified enzyme was shown to retain its thermo-activity as well as a great tolerance to high concentration of NaCl and imidazole.
- [Show abstract] [Hide abstract]
ABSTRACT: Background Reactive oxygen species play a key role in the development of many dermatological disorders. Objective The purpose of this study is to examine the lipid peroxidation, protein oxidation and antioxidative profile in Tunisian pemphigus foliaceus (PF) patients. Methods Malondialdehyde (MDA), conjugated dienes (CD), protein thiol levels, catalase (CAT) and superoxide dismutase (SOD) activities were evaluated in skin biopsies of 13 patients compared to biopsies of 7 healthy controls. Results Oxidative stress was confirmed in these three types of patient biopsies as compared to controls. Thus, MDA, CD levels and catalase CAT and SOD activities were significantly increased in lesional, perilesional and normal biopsies of PF patients than in those of control subjects. Protein oxidative was confirmed by lower levels of protein thiols in lesional, perilesional and normal biopsies than in control's biopsies. Otherwise, in patients, a significant rise of these biomarkers was observed in lesional and perilesional biopsies compared with normal biopsies. Conclusion This study shows that oxidative stress could be involved in the pathogenesis of PF by the spread of skin lesions and/or by the increase in auto-antibodies' reactivity.
- [Show abstract] [Hide abstract]
ABSTRACT: Interest in biosurfactants has increased considerably in recent years, as they are potentially used in many commercial applications in petroleum, pharmaceuticals, biomedical, and food processing industries. Since improvement of their production was of great importance to reduce the final coast, cultural conditions were analyzed to optimize biosurfactants production from Bacillus subtilis SPB1 strain. A high yield of biosurfactants was obtained from a culture of B. subtilis using carbohydrate substrate as a carbon source; among carbohydrates, glucose enhanced the best surfactin production. The optimum glucose concentration was 40 g/L. Higher amount of biosurfactants was obtained using 5 g/L of urea as organic nitrogen source and applying C/N ratio of 7 with ammonium chloride as inorganic nitrogen source. The highest amount of biosurfactants was recorded with the addition of 2% kerosene. Moreover, it was shown, using an automated full-controlled 2.6 L fermenter, that aeration of the medium, which affected strongly the growth regulated biosurfactants synthesis by the producing cell. So that, low or high aerations lead to a decrease of biosurfactants synthesis yields. It was found that when using dissolved oxygen saturation of the medium at 30%, biosurfactants production reached 4.92 g/L.
Information provided on this web page is aggregated encyclopedic and bibliographical information relating to the named institution. Information provided is not approved by the institution itself. The institution’s logo (and/or other graphical identification, such as a coat of arms) is used only to identify the institution in a nominal way. Under certain jurisdictions it may be property of the institution.
Rg score distribution
No data available.