| dc.description.abstract | Red pigmented marine bacteria, Pseudoalteromonas rubra
strains PS1 and SB14, were isolated from two sampling locations in different
ecosystems on Alor Island, Indonesia, and cultured in the laboratory. We
analyzed the 16S rRNA gene sequences and examined the pigment
composition and found that both strains produced cycloprodigiosin (3),
prodigiosin (4), and 2-methyl-3-hexyl-prodiginine (5) as major compounds.
In addition, we detected three minor compounds: prodigiosin derivatives 2-
methyl-3-propyl prodiginine (1), 2-methyl-3-butyl prodiginine (2), and 2-
methyl-3-heptyl-prodiginine (6). To our knowledge, this is the first report
that P. rubra synthesizes not only prodigiosin and cycloprodigiosin but also
four prodigiosin derivatives that differ in the length of the alkyl chain. The
antimicrobial activity of cycloprodigiosin, prodigiosin, and 2-methyl-3-hexyl-prodiginine was examined by a disk-diffusion test
against Escherichia coli, Staphylococcus aureus, Salmonella typhi, and Candida albicans. We found that, at a concentration of 20 μg/mL,
cycloprodigiosin showed the greatest inhibition (25.1 ± 0.55 mm) against S. aureus. | en_US |
