الفهرس 
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Abstract
A bioactive actinomycete isolated from a cultivated soil sample in El-Sharkia Governorate ,Egypt showed obvious antibacterial activity against 46 different clinical pathogenic bacteria were isolated from Zagazig University Hospital .It was identified as species related to genus Streptomyces using conventional methods depending on morphological and biochemical characteristics. Partial amplification and sequence analysis of 16s rRNA gene confirmed identity of the bioactive strain as Streptomyces erythrogriseus sub sp 2, and it was submitted in Gene Bank under accession number LC052669. from the antibiotic susceptibility profile (using 20 different antibiotics) of the 46 were tested clinical isolates,5 were selected as multi drug resistant isolates. The bioactive product was extracted by using butanol solvent followed by chromatographic purification. The active fractions were concentrated and identified on the bases of the recommended key’s for identification of antibiotics.
The physico chemical analysis predicted the empirical formula C38H94O18N4S2. The collected data emphasized that the molecular weight of the present antibiotic is considered to equal 957 m/z the Rf was determined at 0.34. There is no previous literature of such novel antibiotic. The MIC and MBC values of purified fractions against the 5 selected multi drug resistant isolates ranged between 100 to 120 µl/ml and 120 to 180µl/ml, respictively.
The bacterial isolate identified as B.cereus (54-1) and it was submitted in the Gene Bank under accession number LC052670 .
The bioactive product produced B.cereus (54-1) was extracted by using ammonium sulphate preciptation followed by chromatographic purification. The active fractions were collected and the physicocemical analysis indicated that, the amino acid sequence of the (BLS)showed that, it was consists of 16 amino acids as following X Asp , Thr , Ser , Glu , Gly , Ala , Val , Met , Iso , Leu , Tyr , Phe , His , Lys , Arg and Pro. The amino acid composition supports the explanation that BLS contains acidic residues ( Asp and Glu ) and basic residues (Lys and His) . the peak for the molecular weight is the exact molecular weight of the produced substance is 80, the U.V. spectrum of the purified (BLS) which indicates that the base peaks at 216.50 and 204.50 wavelength.
The MIC and MBC vales of purified fraction against the five selected multi-drug resistant isolates ranged between 500(AU) to 800(AU) and 500 to 800(AU),respectively. Efficiency of the purified compounds to antagonize some plant pathogenic fungi that the tested pathogenic fungi can be arranged in the following descending order according to the diameter of inhibition zone using Actinomycete isolates Asp. flavus>Fus.solani17> Asp. flavus.Tbot> Fus.solani 2. strains.
Studying the effect of purified two substances on viability of sensitive species bioactive compound and BLS degraded cell wall protein so that increase the release of intercellular U.V. materials of the tested organisms. Studying the effect of purified substances on the integrity of treated cells macromolecules protein cell membrane.