Liquid Chromatography-Mass Spectrometry-Based Rapid Secondary-Metabolite Profiling of Marine Pseudoalteromonas sp. M2

Abstract

The ocean is a rich resource of flora, fauna, and food. A wild-type bacterial strain showing confluent growth on marine agar with antibacterial activity was isolated from marine water, identified using 16S rDNA sequence analysis as Pseudoalteromonas sp., and designated as strain M2. This strain was found to produce various secondary metabolites including quinolone alkaloids. Using high-resolution mass spectrometry (MS) and nuclear magnetic resonance (NMR) analysis, we identified nine secondary metabolites of 4-hydroxy-2-alkylquinoline (pseudane-III, IV, V, VI, VII, VIII, IX, X, and XI). Additionally, this strain produced two novel, closely related compounds, 2-isopentylqunoline-4-one and 2-(2,3-dimetylbutyl)qunoline-4-(1H)-one, which have not been previously reported from marine bacteria. From the metabolites produced by Pseudoalteromonas sp. M2, 2-(2,3-dimethylbutyl)quinolin-4-one, pseudane-VI, and pseudane-VII inhibited melanin synthesis in Melan-A cells by 23.0%, 28.2%, and 42.7%, respectively, wherein pseudane-VII showed the highest inhibition at 8 µg/mL. The results of this study suggest that liquid chromatography (LC)-MS/MS-based metabolite screening effectively improves the efficiency of novel metabolite discovery. Additionally, these compounds are promising candidates for further bioactivity development.

Bromination of alkyl quinolones by Microbulbifer sp. HZ11, a marine Gammaproteobacterium, modulates their antibacterial activity

“…SWAT5, Pseudoalteromonas piscicid a and Pseudoalteromonas sp. M2 were shown to attenuate the growth of Vibrio harveyi , V. anguillarum , a marine cyanobacterium of the genus Synechococcus , various diatom species, and the bloom‐forming coccolithophore Emiliania huxleyi (Wratten et al ., ; Long et al ., ; Harvey et al ., ; Kim et al ., ). HHQ and PQS production were also reported for P. bermudensis , a symbiont of the chlorophyte Tetraselmis striata .…”

“…In particular, the complex ecosystems of biotic surfaces appear to promote the diversification of secondary metabolites to mediate dynamic inter-species and inter-domain interactions (Penesyan et al, 2010;Giordano et al, 2015). Among the variety of microbial secondary metabolites, 2-alkyl-1(H)-quinolin-4-ones [hereafter referred to as alkyl quinolones (AQs)] have been found to be produced by a number of marine representatives of the Pseudomonas, Alteromonas and Pseudoalteromonas clades as well as the Alphaproteobacterium Pelagibaca bermudensis (Wratten et al, 1977;Debitus et al, 1998;Bultel-Poncé et al, 1999;Long et al, 2003;Vynne et al, 2011;Whalen et al, 2015;Harvey et al, 2016;Kim et al, 2016;Patidar et al, 2018).…”

Pseudane-VII Isolated from Pseudoalteromonas sp. M2 Ameliorates LPS-Induced Inflammatory Response In Vitro and In Vivo

“…We recently reported that liquid chromatography–mass spectrometry-based rapid secondary-metabolite profiling of marine Pseudoalteromonas sp. M2, and isolated various pseudane compounds as secondary-metabolites, and found pseudane compounds has anti-melanogenic effect [ 14 ].…”

Statistical optimization and valuable applications of bioactive compounds produced by marine Pseudoalteromonas piscicida

“…IR spectra of the active compound showed peaks at 3448 , 300.15 cm -1 (O-H stretching), 2135.67 cm -1 (C-H alkane), 1714, 1640.38 cm -1 (C=O stretching), 1361.90, 1422.08 cm -1 (C= C aromatic), 1221,.28 1092.22 cm -1 (Aromatic C-O). The major chemical component Di-n-octyl phthalate was proven to have pharmaceutical uses as was reported by Kim et al (2004) who stated that phthalates which include butyl benzyl phthalate (BBP), di(n-butyl) phthalate (DBP), and di (2 ethylhexyl) phthalate (DEHP) had been demonstrated anticancer activity. Moreover, phenolic compounds exhibits antimicrobial activity (Patra and Baek, 2016;Rodríguez-Pérez et al, 2016;Marín et al, 2016;Tuberoso et al, 2016) and may reduce the risk of cardiovascular disease and stroke In these ways, phenolic compounds may also confer protection against chronic diseases such as atherosclerosis and assist in the management of menopausal symptoms.…”

“…Marine bacteria of the genus Pseudoalteromonas are recognized as major producers of various biologically active metabolites such as halogenated compounds, cyclic compounds, enzymes (Secun et al, 2015). Kim et al (2016) reported the production of various secondary metabolites from the genus Pseudoalteromonas against E.coli. …”