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In this study, the soil from the Tianmu Mountain Nature Reserve was isolated against Gram-positive bacteria, Gram-negative bacteria and fungi are resistant bacterial strains producing B69. The morphological, physiological and biochemical characteristics and 16S rDNA sequence analysis, it was identified as Paenibacillus Paenibacillus elgii. In this study, MCI GEL CHP20P column and HPLC methods such isolated from the fermentation broth or two antibiotic substances, named PelgipeptinA and B, ESI-MS results indicate their molecular weights of 1072 and 1100 Da. With ESI-CID-MS and amino acid analysis to determine the possible level Pelgipeptin A structure L-Dab-D-Val-L-Leu/Ile-L-Ser-Y1-L-Dab-L-Val-L-Dab -D-Phe-L-Leu/Ile, Pelgipeptin B for L-Dab-D-Val-L-Leu/Ile-L-Ser-Y2-L-Dab-L-Leu/Ile-L-Dab-D -Phe-L-Leu/Ile, wherein Y is a structure of fatty acid chains. And structure of non-protein source of amino acids containing known antibiotic Dab for comparison and found Pelgipeptins avermectin family members and peptide structure is very similar, can be determined they belong to this family. Permetin A Pelgipeptin B and the same molecular weight, the structure is very similar, which may be the same substance. The Pelgipeptin A and any chemical structure of an antibiotic are not identical can be identified as a new antibiotic. This article also on the stability of antibiotics in vitro antibacterial activity and antibacterial activity of plants were studied. In the stability experiments, antibiotic treatment at 60 ℃ for 2 h, antibacterial activity basically unchanged, at pH1.0-8.0 in handling overnight activity is not affected, but in the pH9.0, 10.0, the activity was significantly decreased in pH11.0, 12.0, then the complete inactivation. Vitro experiments found, Pelgipeptin A and B in the experiment are resistant to all of the indicator bacteria, including the drug-resistant Staphylococcus epidermidis CMCC 26069 (resistant to ampicillin) The minimum inhibitory concentration (MIC) values ??were 3.12 and 0.78μg/ml, showing a strong inhibitory effect, indicating that with the development of the pharmaceutical Pelgipeptins potential antimicrobial agents. In addition, Pelgipeptins also has strong anti-fungal ability, can inhibit a variety of soil-borne diseases fungal growth, MIC value 6.25-50μg/ml. Antibacterial experiment in plants, 250μg/ml partially purified antibiotic (PPA) on a variety of prevention and treatment of plant diseases have a certain effect, in which the rice sheath blight efficiency of 81.98% against, which indicates a potential biocontrol antibiotic application prospects.
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