Project description:Queen conch are among the most economically, socially, and culturally important fishery resources in the Caribbean. Despite a multitude of fisheries management measures enacted across the region, populations are depleted and failing to recover. It is believed that queen conch are highly susceptible to depensatory processes, impacting reproductive success and contributing to the lack of recovery. We developed a model of reproductive dynamics to evaluate how variations in biological factors such as population density, movement speeds, rest periods between mating events, scent tracking, visual perception of conspecifics, sexual facilitation, and barriers to movement affect reproductive success and overall reproductive output. We compared simulation results to empirical observations of mating and spawning frequencies from conch populations in the central Bahamas and Florida Keys. Our results confirm that low probability of mate finding associated with decreased population density is the primary driver behind observed breeding behavior in the field, but is insufficient to explain observed trends. Specifically, sexual facilitation coupled with differences in movement speeds and ability to perceive conspecifics may explain the observed lack of mating at low densities and differences between mating frequencies in the central Bahamas and Florida Keys, respectively. Our simulations suggest that effective management strategies for queen conch should aim to protect high-density reproductive aggregations and critical breeding habitats.
Project description:A new antibacterial 3-monoacyl-sn-glycerol, nostochopcerol (1), was isolated from a cultured algal mass of the edible cyanobacterium Nostochopsis lobatus MAC0804NAN. The structure of compound 1 was established by the analysis of NMR and MS data while its chirality was established by comparison of optical rotation values with synthetically prepared authentics. Compound 1 inhibited the growth of Bacillus subtilis and Staphylococcus aureus at MIC of 50 μg/mL and 100 μg/mL, respectively.
Project description:Genotoxic estrogen metabolites generate various endogenous DNA lesions but their carcinogenesis mechanisms have been overlooked by well-known cell proliferation pathways through estrogen receptor (ER). Genome-wide sequencing using click probe enrichment coupled with liquid chromatography-mass spectrometry (click probe-Seq/LCMS2) was developed to identify damaged genes and characterize global generation profiles of depurinating and stable adducts induced by 4-hydrolyxyl estradiol (4OHE2) in MCF-7 chromatin. Both data were combined to show guanine nucleobase in GC-rich transcription-relevant domain are main target sites. The damage abundance exhibited positive correlation with DNase hypersensitive sites, indicating 4OHE2 attacks chromatin exposure region beyond ER binding. Cell-based comparability studies indicated accumulated 4OHE2 caused suppressed transcription of target genes, in-effective damage repair, and decreased cell viability, differing from uncontrolled cell growth by extensive ER-signaling. Click probe-Seq/LCMS2 approach revealed the first chromatin damage map by endogenous metabolites, exposing a previously unexplored landscape in cancer research and being applicable to other genotoxic species.