Detection of secreted antimicrobial peptides isolated from cell-free culture supernatant of Paenibacillus alvei AN5

Abstract

An antimicrobial substance produced by the Paenibacillus alvei strain AN5 was detected in fermentation broth. Subsequently, cell-free culture supernatant (CFCS) was obtained by medium centrifugation and filtration, and its antimicrobial activity was tested. This showed a broad inhibitory spectrum against both Gram-positive and -negative bacterial strains. The CFCS was then purified and subjected to SDS-PAGE and infrared spectroscopy, which indicated the proteinaceous nature of the antimicrobial compound. Some de novo sequencing using an automatic Q-TOF premier system determined the amino acid sequence of the purified antimicrobial peptide as Y-S-K-S-L-P-L-S-V-L-N-P (1,316 Da). The novel peptide was designated as peptide AN5-1. Its mode of action was bactericidal, inducing cell lysis in E. coli ATCC 29522 and S. aureus, and non-cell lysis in both S. marcescens and B. cereus ATCC 14579. Peptide AN5-1 displayed stability at a wide range of pH values (2–12) and remained active after exposure to high temperatures (100 °C). It also maintained its antimicrobial activity after incubation with chemicals such as SDS, urea and EDTA.

Terrestrial and marine Antarctic fungi extracts active against Xanthomonas citri subsp. citri

“…Curiously, there are a few works about the antimicrobial activity of intracellular extracts either against bacteria or fungi. Alkotaini et al (2013) reported the production of an intracellular antimicrobial peptide by a strain of Paenibacillus alvei, which demonstrates the capacity to have not only extracellular compounds with interesting characteristics, but also nonsecreted molecules of importance. Some assumptions can be made regarding the outcome of intracellular extracts showing activity against the citrus canker pathogen.…”

Bioremediation of Oil-Based Paint from Aqueous Media by Novel Indigenous Brevibacillus parabrevis Strain NAP3 and its Toxicity Assessment

“…Alkotaini et al [38] found that cell-free culture supernatant displayed a wide-range inhibitory spectrum in opposition together with Grampositive and -negative bacterial strains with the action of bactericidal against E. coli and S. aureus, while there was no activity against Staphylococcus marcescens and B. cereus. Similarly, the cell-free culture supernatant of B. parabrevis without glucose after treatment displayed complete toxicity removal against bacteria.…”

“…On the other hand, treatment with glucose has displayed toxicity against pseudomonas only and complete removal against M. luteus and S. typhi (Table 3). Similarly, the CFCS of Paenibacillus alvei displayed its antimicrobial activity in opposition to E. coli, S. aureus S. marcescens, and B. cereus [38]. In contrast, Milillo et al [39] reported the effective inhibiting growth of Listeria monocytogenes using cellfree culture supernatant from the lactic acid bacteria at very low MIC.…”

Antimicrobial and Antioxidant Activity of Endophyte Bacteria Associated with Curcuma longa Rhizome

“…Paenibacillus alvei are common found in honeybee colonies , soil , milk, mosquito larvae, the wax mot, humans and very rarely pathogenic for vertebrates. It has reported that Paenibacillus alvei produce antimicrobial substance: paenibacillin P and paenibacillin N [23], peptide AN5-1 [24], cyclic lipopeptides [25], depsipeptide [26]. Some of the antimicrobial substance show active againts pathogen S. aures and C. albicans [23,24,26,27] [16,28,29].…”