skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

Explore Research Products in the PAR
It may take a few hours for recently added research products to appear in PAR search results.


  • NSF Public Access
  • Search Results
  • Secondary metabolism of Microcystis : current understanding and recent advances in unlocking genomic and chemical diversity
Title: Secondary metabolism of Microcystis : current understanding and recent advances in unlocking genomic and chemical diversity
ABSTRACT The cyanobacterial genusMicrocystisis globally distributed and known for its ability to produce microcystins, a structurally diverse group of cyanotoxins. However, the biosynthetic capacity ofMicrocystisis vast; its diverse genomes contain a variety of biosynthetic gene clusters (BGCs) encoding the synthesis of metabolites that may be toxic, have important ecological function, or have applications for biotechnology or drug discovery. Recent studies illustrate that these BGCs vary significantly acrossMicrocystisstrains, can be highly expressed in environmental conditions, and may play key roles in cellular physiology, grazer deterrence, and microbial interactions. However, many of these BGCs and metabolites remain poorly characterized or completely uncharacterized, having been identified only through genome sequencing or mass spectrometry, respectively, leaving no knowledge of their structure, bioactivity, or physiological or ecological functions. Here, we synthesize the current body of knowledge regarding the secondary metabolism ofMicrocystisin terms of genetic and chemical diversity, potential drivers of synthesis, and physiological and ecological functions. This review highlights the need for further research to characterize the largely unexplored genetic and chemical diversity ofMicrocystisin communities in the environment and discusses the challenges and opportunities of integrating high-throughput multiomic approaches to link uncharacterized gene clusters with their corresponding metabolites.Microcystiswill continue to be a rich source for secondary metabolite research as its genetic and chemical potential likely plays a critical role in the persistence and observed dynamics of harmful algal blooms and may harbor uncharacterized toxins and metabolites.  more » « less
Award ID(s):
2418066
PAR ID:
10660793
Author(s) / Creator(s):
; ;
Editor(s):
Dudley, Edward G
Publisher / Repository:
American Society for Microbiology
Date Published:
Journal Name:
Applied and Environmental Microbiology
ISSN:
0099-2240
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. ; ; ; ; ; ; ; (, mSystems)
    van_der_Hooft, Justin_J J (Ed.)
    ABSTRACT Microcystisspp. are renowned for producing the hepatotoxin microcystin in freshwater cyanobacterial harmful algal blooms around the world, threatening drinking water supplies and public and environmental health. However,Microcystisgenomes also harbor numerous biosynthetic gene clusters (BGCs) encoding the biosynthesis of other secondary metabolites, including many with toxic properties. Most of these BGCs are uncharacterized and currently lack links to biosynthesis products. However, recent field studies show that many of these BGCs are abundant and transcriptionally active in natural communities, suggesting potentially important yet unknown roles in bloom ecology and water quality. Here, we analyzed 21 xenicMicrocystiscultures isolated from western Lake Erie to investigate the diversity of the biosynthetic potential of this genus. Through metabologenomic andin silicoapproaches, we show that theseMicrocystisstrains contain variable BGCs, previously observed in natural populations, and encode distinct metabolomes across cultures. Additionally, we find that the majority of metabolites and gene clusters are uncharacterized, highlighting our limited understanding of the chemical repertoire ofMicrocystisspp. Due to the complex metabolomes observed in culture, which contain a wealth of diverse congeners as well as unknown metabolites, these results underscore the need to deeply explore and identify secondary metabolites produced byMicrocystisbeyond microcystins to assess their impacts on human and environmental health.IMPORTANCEThe genusMicrocystisforms dense cyanobacterial harmful algal blooms (cyanoHABs) and can produce the toxin microcystin, which has been responsible for drinking water crises around the world. While microcystins are of great concern,Microcystisalso produces an abundance of other secondary metabolites that may be of interest due to their potential for toxicity, ecological importance, or pharmaceutical applications. In this study, we combine genomic and metabolomic approaches to study the genes responsible for the biosynthesis of secondary metabolites as well as the chemical diversity of produced metabolites inMicrocystisstrains from the Western Lake Erie Culture Collection. This unique collection comprisesMicrocystisstrains that were directly isolated from western Lake Erie, which experiences substantial cyanoHAB events annually and has had negative impacts on drinking water, tourism, and industry. 
    more » « less
  2. ; ; ; ; ; ; ; ; ; ; et al (, Applied and Environmental Microbiology)
    Biddle, Jennifer F (Ed.)
    ABSTRACT The Winam Gulf in the Kenyan region of Lake Victoria experiences prolific, year-round cyanobacterial harmful algal blooms (cyanoHABs) which pose threats to human, livestock, and ecosystem health. To our knowledge, there is limited molecular research on the gulf’s cyanoHABs, and thus, the strategies employed for survival and proliferation by toxigenic cyanobacteria in this region remain largely unexplored. Here, we used metagenomics to analyze the Winam Gulf’s cyanobacterial composition, function, and biosynthetic potential.Dolichospermumwas the dominant bloom-forming cyanobacterium, co-occurring withMicrocystisat most sites.MicrocystisandPlanktothrixwere more abundant in shallow and turbid sites. Metagenome-assembled genomes (MAGs) ofDolichospermumharbored nitrogen fixation genes, suggesting diazotrophy as a potential mechanism supporting the proliferation ofDolichospermumin the nitrogen-limited gulf. Over 300 biosynthetic gene clusters (BGCs) putatively encoding the synthesis of toxins and other secondary metabolites were identified across the gulf, even at sites where there were no visible cyanoHAB events. Almost all BGCs identified had no known synthesis product, indicating a diverse and novel biosynthetic repertoire capable of synthesizing harmful or potentially therapeutic metabolites.MicrocystisMAGs containedmcygenes encoding the synthesis of hepatotoxic microcystins which are a concern for drinking water safety. These findings illustrate the spatial variation of bloom-forming cyanobacteria in the Winam Gulf and their available strategies to dominate different ecological niches. This study underscores the need for further use of genomic techniques to elucidate the dynamics and mitigate the potentially harmful effects of cyanoHABs and their associated toxins on human, environmental, and economic health. 
    more » « less
  3. ; ; ; (, mSphere)
    Campbell, Barbara J (Ed.)
    ABSTRACT Photoautotrophic diazotrophs, specifically the generaTrichodesmiumand UCYN-A, play a pivotal role in marine nitrogen cycling through their capacity for nitrogen fixation. Despite their global distribution, the microdiversity and environmental drivers of these diazotrophs remain underexplored. This study provides a comprehensive analysis of the global diversity and distribution ofTrichodesmiumand UCYN-A using the nitrogenase gene (nifH) as a genetic marker. We sequenced 954 samples from the Pacific, Atlantic, and Indian Oceans as part of the Bio-GO-SHIP project. Our results reveal significant phylogenetic and biogeographic differences between and within the two genera.Trichodesmiumexhibited greater microdiversity compared to UCYN-A, with clades showing region-specific distribution.Trichodesmiumclades were primarily influenced by temperature and nutrient availability. They were particularly frequent in regions of phosphorus stress. In contrast, UCYN-A was most frequently observed in regions experiencing iron stress. UCYN-A clades demonstrated more homogeneous distributions, with a single sequence variant within the UCYN-A1 clade dominating across varied environments. The biogeographic patterns and environmental correlations ofTrichodesmiumand UCYN-A highlight the role of microdiversity in their ecological adaptation and reflect their different ecological strategies. These findings underscore the importance of characterizing the global patterns of fine-scale genetic diversity to better understand the functional roles and distribution of marine nitrogen-fixing photoautotrophs.IMPORTANCEThis study provides insights into the global diversity and distribution of nitrogen-fixing photoautotrophs, specificallyTrichodesmiumand UCYN-A. We sequenced 954 oceanic samples of thenifHnitrogenase gene and uncovered significant differences in microdiversity and environmental associations between these genera.Trichodesmiumshowed high levels of sequence diversity and region-specific clades influenced by temperature and nutrient availability. In contrast, UCYN-A exhibited a more uniform distribution, thriving in iron-stressed regions. Quantifying these fine-scale genetic variations enhances our knowledge of their ecological roles and adaptations, emphasizing the need to characterize the genetic diversity of marine nitrogen-fixing prokaryotes. 
    more » « less
  4. ; ; (, Microbiology Resource Announcements)
    Pritchard, Leighton (Ed.)
    ABSTRACT The fungusAspergillus melleusis an important biosynthesis host for varied commercial applications. Gene annotation of a previously published genome produced 12,841 protein-coding genes and identified 102 biosynthetic gene clusters. 
    more » « less
  5. ; ; ; ; ; ; ; ; (, Microbiology Resource Announcements)
    Bruno, Vincent Michael (Ed.)
    ABSTRACT The fungusConoideocrella luteorostratais a recently discovered pathogen of invasive elongate hemlock scale insects (EHS;Fiorinia externa) in Christmas tree farms in the eastern U.S. Here, we report a scaffold-level genome and assembly along with an initial survey of biosynthetic gene clusters for strain ARSEF 14590 from EHS. 
    more » « less
  • Citation Formats
  • MLA
  • APA
  • Chicago
  • BibTeX
  • Text Encoded Conversion
  • XML
  • Save / Share this Record
  • Send to Email