CHEMICAL PROFILING OF A MARINE-DERIVED, GRAM-NEGATIVE BACTERIA: ACHROMOBACTER SPANIUS
Alexis Munoz, Christine Theodore, Patrick Still, Phil Crews.
University of California, Santa Cruz, Santa Cruz, CA.
Secondary metabolites, unlike primary metabolites, are not involved in growth, development, or reproduction of an organism and often play a role in chemical defense and communication. Within the marine environment, secondary metabolites from non-photosynthetic Gram-negative bacteria are considered to be a promising source of new natural products. A bacterial strain that was isolated from a backshore (dry sand) sample collected at Zmudowski State Beach in California was identified as Achromobacter spanius: 100% identical to A. spanius by partial 16S rRNA gene sequence. The ethyl acetate crude extract of a liquid culture of this strain was subjected to pre-fractionation by high performance liquid chromatography (HPLC). The pre-fractions were analyzed using ultra high performance liquid chromatography (UPLC) and high-resolution accurate mass spectroscopy. The masses, accurate to 4 decimal places, obtained for each peak (A-R) were used to generate molecular formulas. These molecular formulas were then used to search compound databases such as Dictionary of Natural Products (DNP) and ChemSpider, with the goal of prioritizing the isolation of potentially new natural products. On examination of the mass spectra data obtained by the Orbitrap for peaks A-R, peak J proved to have an interesting mass due to its few matches in databases DNP and Chemspider. Further examination of peak J revealed 2 potential molecular formulas through the dereplication process of F-4 fraction, indicating a potential structure (C14H33N4O4S) sulfaquinoxaline.