During the history of civilizations, advanced wood decay results from exposure to various agents for long periods of time. Bio-deterioration, under the influence of living organisms like fungi, can cause massive damage to historical monuments. In this work, we found that fungi participating in wood degradation share a single strategy for degrading wood polymers by secreting enzymes that break down the main constituents of wood such as cellulose, hemicellulose and lignin. While Penicillium commune, Penicillium granulatum and Penicillium chrysogenum showed the highest cellulase productivity and are therefore the most destructive for timber, other fungal species participate also in this biodegradation including Penicillium crustosum, Penicillium expansum Cladosporium cladosporioides and a cellulotic specie Thielavia hyalocarpa that we describe here for the first time.

The resistance of mycobacteria to the clinical applied antibiotics poses a serious problem to deal with the infections they cause. So, the search for new antibiotics active against these bacteria becomes urgent. We report here the isolation from a Moroccan biotope of a bacterial strain secreting an active substance of protein nature that inhibits the growth of several mycobacterial species (Mycobacterium smegmatis; M. aurum A+; M. vaccae; M. bovis BCG and M. kansasii). PCR amplification and DNA sequencing of the 16S ribosomal RNA gene allowed the identification of this strain as Staphylococcus haemolyticus. Moreover, the substance produced by this strain was able to lyse the wall of M. smegmatis and to extract its genomic DNA indicating that it acts probably, like others anti-mycobacterial antibiotics, on this envelope. The identification and characterisation of the active substance would open the way for further technological and therapeutic investigations.

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The treatment of tuberculosis has become more difficult with the worldwide spread of multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains of Mycobacterium tuberculosis. Moreover, the prevalence of human disease caused by atypical mycobacteria has also increased in the past two decades and has further complicated the problem of the treatment of mycobacterial infections. It is therefore urgent to develop new highly active molecules against these bacteria. The present study reports the isolation from a Moroccan soil of a Bacillus strain that exhibits an important antimycobacterial activity. The strain was identified as Brevibacillus laterosporus using DNA sequencing of the 16S ribosomal RNA gene. The antimycobacterial activity was assigned to a substance with a protein nature. This nature was revealed using a liquid-liquid extraction with organic solvents, precipitation with ammonium sulfate and treatment with a protease. This study suggested the identification and the characterization of this active metabolite enabling therapeutic investigations further.

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ABSTRACT:The development of potential antibacterial requires the synthesis of a new series of 5-Chloroisatin derivatives incorporating various aromatic aldehydes in the case 1,3-Dipolar Cycloaddition including Nitrile oxide, as well as the cycloaddition Alcyne-Azide Catalytic with Copper. The charcterization of the structure of the synthesized compounds was confirmed by means of their IR, 1 H-NMR and 13 C-NMR spectral data. In addition, the antibacterial properties in vitro were tested against certain microorganisms using the disk diffusion technique. A majority of compounds show better activity against several of the microorganisms.

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Objective: Research and characterization of new thermostable lipases from bacterial strains isolated from tannery waters in the old medina of Fez. Methods: Gene which encodes the 16S ribosomal RNA for a bacterial species was amplified via PCR and sequenced (Bacillus pumilus HF544325). The extracellular lipase from B. pumilus is purified by gel filtration (Sephacryl S-200) and cation exchange chromatography (Mono S sepharose cation exchanger). The N-terminal sequences of purified Bacillus pumilus lipase were determined by automated Edman's degradation, using an Applied Biosystems 470 A protein sequencer equipped with PTH 120A analyser. The activity of lipase was examined within the pH range of 6.0-10.0 and the effect of pH on lipase stability was determined by incubating the lipase fraction in various buffer solutions ranging from 3.0 to 10.0 for 24 h at room temperature. Results:The results showed that Bacillus pumilus is a strain that produce non-inducible lipase. This enzyme has a molecular weight of 27 kDa and presents a maximal activity at pH 8 and 45°C. The 18 N-terminal amino acid residues showed a high degree of homology with other Bacillus lipase sequences. After treatment in 100°C for 5 min, the thermostable enzyme maintains 60% of its activity, which is greater than that those founded in previous works. The enzyme retained 100% of its activity after 30 min incubation at 70°C. Conclusion: This newly isolated lipase is thermostable and it has a significant difference which was observed when the biochemical properties of the Bacillus pumilus lipase were compared to others microbial lipases. The Bacillus pumilus lipase can be considered as a good candidature for industrial and biotechnological applications. Key Words: Bacillus pumilus, lipase, purification, thermostable Conflict of Interest: The authors have no conflict of interest. ÖZETAmaç: Çalışmanın amacı Fez şehrinde bulunan tabakhane sularından izole edilen bakteri suşla-rından, sıcaklığa dayanıklı yeni bir lipaz enzimini saflaştırarak karakterize etmektir. Metod: Bakteri türleri için 16S ribosomal RNA'yı kodlayan gen PCR ile çoğaltılarak sekanslanmıştır (Bacillus pumilus HF544325). Ekstraselüler lipaz jel filtrasyonu (Sefakril S-200) ve katyon değiştirici kromatografi kullanılarak (Mono S Sefaroz katyon değiştirici) B. pumilus'den saflaştırılmıştır. Saflaştırılan Bacillus pumilus lipazının N-terminal dizisi Edman degredasyon yöntemi (Applied Biosystems 470 A protein sekanslama cihazı ile PTH120A analizör) ile saptanmıştır. Lipaz aktivitesi 6.0-10.0 pH aralığında incelenmiş, pH'nın lipaz enziminin dayanık-lılığına olan etkisi lipaz fraksiyonunu pH'sı 3.0 ile 10.0 arasında değişen çeşitli tampon çözel-tilerinde 24 saat oda sıcaklığında inkübe ederek araştırılmıştır. Bulgular: Sonuçlar Bacillus pumilus suşunun indüklenmeyen lipaz enzimini ürettiğini gös-termektedir. Lipaz enzimi 27 kDa molekül ağırlığına sahip olup, en yüksek aktiviteyi pH 8 ve 45°C'de göstermektedir. Amino ucundaki 18 amino asit diğer Bacillus lipaz dizileri ile yüksek oranda ...