skip to main content

Explore Research Products in the NSF-PAR

  • NSF Public Access
  • Search Results
  • Genomic Analysis of the Yet-Uncultured Binatota Reveals Broad Methylotrophic, Alkane-Degradation, and Pigment Production Capacities
Title: Genomic Analysis of the Yet-Uncultured Binatota Reveals Broad Methylotrophic, Alkane-Degradation, and Pigment Production Capacities
ABSTRACT The recent leveraging of genome-resolved metagenomics has generated an enormous number of genomes from novel uncultured microbial lineages yet left many clades undescribed. Here, we present a global analysis of genomes belonging to Binatota (UBP10), a globally distributed, yet-uncharacterized bacterial phylum. All orders in Binatota encoded the capacity for aerobic methylotrophy using methanol, methylamine, sulfomethanes, and chloromethanes as the substrates. Methylotrophy in Binatota was characterized by order-specific substrate degradation preferences, as well as extensive metabolic versatility, i.e., the utilization of diverse sets of genes, pathways, and combinations to achieve a specific metabolic goal. The genomes also encoded multiple alkane hydroxylases and monooxygenases, potentially enabling growth on a wide range of alkanes and fatty acids. Pigmentation is inferred from a complete pathway for carotenoids (lycopene, β- and γ-carotenes, xanthins, chlorobactenes, and spheroidenes) production. Further, the majority of genes involved in bacteriochlorophyll a , c , and d biosynthesis were identified, although absence of key genes and failure to identify a photosynthetic reaction center preclude proposing phototrophic capacities. Analysis of 16S rRNA databases showed the preferences of Binatota to terrestrial and freshwater ecosystems, hydrocarbon-rich habitats, and sponges, supporting their potential role in mitigating methanol and methane emissions, breakdown of alkanes, and their association with sponges. Our results expand the lists of methylotrophic, aerobic alkane-degrading, and pigment-producing lineages. We also highlight the consistent encountering of incomplete biosynthetic pathways in microbial genomes, a phenomenon necessitating careful assessment when assigning putative functions based on a set-threshold of pathway completion. IMPORTANCE A wide range of microbial lineages remain uncultured, yet little is known regarding their metabolic capacities, physiological preferences, and ecological roles in various ecosystems. We conducted a thorough comparative genomic analysis of 108 genomes belonging to the Binatota (UBP10), a globally distributed, yet-uncharacterized bacterial phylum. We present evidence that members of the order Binatota specialize in methylotrophy and identify an extensive repertoire of genes and pathways mediating the oxidation of multiple one-carbon (C 1 ) compounds in Binatota genomes. The occurrence of multiple alkane hydroxylases and monooxygenases in these genomes was also identified, potentially enabling growth on a wide range of alkanes and fatty acids. Pigmentation is inferred from a complete pathway for carotenoids production. We also report on the presence of incomplete chlorophyll biosynthetic pathways in all genomes and propose several evolutionary-grounded scenarios that could explain such a pattern. Assessment of the ecological distribution patterns of the Binatota indicates preference of its members to terrestrial and freshwater ecosystems characterized by high methane and methanol emissions, as well as multiple hydrocarbon-rich habitats and marine sponges.  more » « less
Award ID(s):
2016423
NSF-PAR ID:
10248390
Author(s) / Creator(s):
; ; ; ; ; ; ;
Editor(s):
Harwood, Caroline S.
Date Published:
Journal Name:
mBio
Volume:
12
Issue:
3
ISSN:
2150-7511
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. ; ; ; ; ; ; ; ; ; ; et al ( , Applied and Environmental Microbiology)
    Nikel, Pablo Ivan (Ed.)
    ABSTRACT Cultured Myxococcota are predominantly aerobic soil inhabitants, characterized by their highly coordinated predation and cellular differentiation capacities. Little is currently known regarding yet-uncultured Myxococcota from anaerobic, nonsoil habitats. We analyzed genomes representing one novel order (o__JAFGXQ01) and one novel family (f__JAFGIB01) in the Myxococcota from an anoxic freshwater spring (Zodletone Spring) in Oklahoma, USA. Compared to their soil counterparts, anaerobic Myxococcota possess smaller genomes and a smaller number of genes encoding biosynthetic gene clusters (BGCs), peptidases, one- and two-component signal transduction systems, and transcriptional regulators. Detailed analysis of 13 distinct pathways/processes crucial to predation and cellular differentiation revealed severely curtailed machineries, with the notable absence of homologs for key transcription factors (e.g., FruA and MrpC), outer membrane exchange receptor (TraA), and the majority of sporulation-specific and A-motility-specific genes. Further, machine learning approaches based on a set of 634 genes informative of social lifestyle predicted a nonsocial behavior for Zodletone Myxococcota . Metabolically, Zodletone Myxococcota genomes lacked aerobic respiratory capacities but carried genes suggestive of fermentation, dissimilatory nitrite reduction, and dissimilatory sulfate-reduction (in f_JAFGIB01) for energy acquisition. We propose that predation and cellular differentiation represent a niche adaptation strategy that evolved circa 500 million years ago (Mya) in response to the rise of soil as a distinct habitat on Earth. IMPORTANCE The phylum Myxococcota is a phylogenetically coherent bacterial lineage that exhibits unique social traits. Cultured Myxococcota are predominantly aerobic soil-dwelling microorganisms that are capable of predation and fruiting body formation. However, multiple yet-uncultured lineages within the Myxococcota have been encountered in a wide range of nonsoil, predominantly anaerobic habitats, and the metabolic capabilities, physiological preferences, and capacity of social behavior of such lineages remain unclear. Here, we analyzed genomes recovered from a metagenomic analysis of an anoxic freshwater spring in Oklahoma, USA, that represent novel, yet-uncultured, orders and families in the Myxococcota . The genomes appear to lack the characteristic hallmarks for social behavior encountered in Myxococcota genomes and displayed a significantly smaller genome size and a smaller number of genes encoding biosynthetic gene clusters, peptidases, signal transduction systems, and transcriptional regulators. Such perceived lack of social capacity was confirmed through detailed comparative genomic analysis of 13 pathways associated with Myxococcota social behavior, as well as the implementation of machine learning approaches to predict social behavior based on genome composition. Metabolically, these novel Myxococcota are predicted to be strict anaerobes, utilizing fermentation, nitrate reduction, and dissimilarity sulfate reduction for energy acquisition. Our results highlight the broad patterns of metabolic diversity within the yet-uncultured Myxococcota and suggest that the evolution of predation and fruiting body formation in the Myxococcota has occurred in response to soil formation as a distinct habitat on Earth. 
    more » « less
  2. ( , bioRxiv)
    null (Ed.)
    Approaches for recovering and analyzing genomes belonging to novel, hitherto unexplored bacterial lineages have provided invaluable insights into the metabolic capabilities and ecological roles of yet-uncultured taxa. The phylum Acidobacteria is one of the most prevalent and ecologically successful lineages on earth yet, currently, multiple lineages within this phylum remain unexplored. Here, we utilize genomes recovered from Zodletone spring, an anaerobic sulfide and sulfur-rich spring in southwestern Oklahoma, as well as from multiple disparate soil and non-soil habitats, to examine the metabolic capabilities and ecological role of members of the family UBA6911 (group18) Acidobacteria. The analyzed genomes clustered into five distinct genera, with genera Gp18_AA60 and QHZH01 recovered from soils, genus Ga0209509 from anaerobic digestors, and genera Ga0212092 and UBA6911 from freshwater habitats. All genomes analyzed suggested that members of Acidobacteria group 18 are metabolically versatile heterotrophs capable of utilizing a wide range of proteins, amino acids, and sugars as carbon sources, possess respiratory and fermentative capacities, and display few auxotrophies. Soil-dwelling genera were characterized by larger genome sizes, higher number of CRISPR loci, an expanded carbohydrate active enzyme (CAZyme) machinery enabling de-branching of specific sugars from polymers, possession of a C1 (methanol and methylamine) degradation machinery, and a sole dependence on aerobic respiration. In contrast, non-soil genomes encoded a more versatile respiratory capacity for oxygen, nitrite, sulfate, trimethylamine N-oxide (TMAO) respiration, as well as the potential for utilizing the Wood Ljungdahl (WL) pathway as an electron sink during heterotrophic growth. Our results not only expand our knowledge of the metabolism of a yet-uncultured bacterial lineage, but also provide interesting clues on how terrestrialization and niche adaptation drives metabolic specialization within the Acidobacteria. 
    more » « less
  3. ; ; ; ; ; ; ; ( , Nature Communications)
    Abstract Geothermal environments, such as hot springs and hydrothermal vents, are hotspots for carbon cycling and contain many poorly described microbial taxa. Here, we reconstructed 15 archaeal metagenome-assembled genomes (MAGs) from terrestrial hot spring sediments in China and deep-sea hydrothermal vent sediments in Guaymas Basin, Gulf of California. Phylogenetic analyses of these MAGs indicate that they form a distinct group within the TACK superphylum, and thus we propose their classification as a new phylum, ‘Brockarchaeota’, named after Thomas Brock for his seminal research in hot springs. Based on the MAG sequence information, we infer that some Brockarchaeota are uniquely capable of mediating non-methanogenic anaerobic methylotrophy, via the tetrahydrofolate methyl branch of the Wood-Ljungdahl pathway and reductive glycine pathway. The hydrothermal vent genotypes appear to be obligate fermenters of plant-derived polysaccharides that rely mostly on substrate-level phosphorylation, as they seem to lack most respiratory complexes. In contrast, hot spring lineages have alternate pathways to increase their ATP yield, including anaerobic methylotrophy of methanol and trimethylamine, and potentially use geothermally derived mercury, arsenic, or hydrogen. Their broad distribution and their apparent anaerobic metabolic versatility indicate that Brockarchaeota may occupy previously overlooked roles in anaerobic carbon cycling. 
    more » « less
  4. ; ; ; ; ; ; ( , mBio)
    Ravel, Jacques (Ed.)
    ABSTRACT Invertebrates, particularly sponges, have been a dominant source of new marine natural products. For example, lasonolide A (LSA) is a potential anticancer molecule isolated from the marine sponge Forcepia sp., with nanomolar growth inhibitory activity and a unique cytotoxicity profile against the National Cancer Institute 60-cell-line screen. Here, we identified the putative biosynthetic pathway for LSA. Genomic binning of the Forcepia sponge metagenome revealed a Gram-negative bacterium belonging to the phylum Verrucomicrobia as the candidate producer of LSA. Phylogenetic analysis showed that this bacterium, here named “ Candidatus Thermopylae lasonolidus,” only has 88.78% 16S rRNA identity with the closest relative, Pedosphaera parvula Ellin514, indicating that it represents a new genus. The lasonolide A ( las ) biosynthetic gene cluster (BGC) was identified as a trans -acyltransferase (AT) polyketide synthase (PKS) pathway. Compared with its host genome, the las BGC exhibits a significantly different GC content and pentanucleotide frequency, suggesting a potential horizontal acquisition of the gene cluster. Furthermore, three copies of the putative las pathway were identified in the candidate producer genome. Differences between the three las repeats were observed, including the presence of three insertions, two single-nucleotide polymorphisms, and the absence of a stand-alone acyl carrier protein in one of the repeats. Even though the verrucomicrobial producer shows signs of genome reduction, its genome size is still fairly large (about 5 Mbp), and, compared to its closest free-living relative, it contains most of the primary metabolic pathways, suggesting that it is in the early stages of reduction. IMPORTANCE While sponges are valuable sources of bioactive natural products, a majority of these compounds are produced in small quantities by uncultured symbionts, hampering the study and clinical development of these unique compounds. Lasonolide A (LSA), isolated from marine sponge Forcepia sp., is a cytotoxic molecule active at nanomolar concentrations, which causes premature chromosome condensation, blebbing, cell contraction, and loss of cell adhesion, indicating a novel mechanism of action and making it a potential anticancer drug lead. However, its limited supply hampers progression to clinical trials. We investigated the microbiome of Forcepia sp. using culture-independent DNA sequencing, identified genes likely responsible for LSA synthesis in an uncultured bacterium, and assembled the symbiont’s genome. These insights provide future opportunities for heterologous expression and cultivation efforts that may minimize LSA’s supply problem. 
    more » « less
  5. ( , Nature communications)
    Microbes in Guaymas Basin (Gulf of California) hydrothermal sediments thrive on hydrocarbons and sulfur and experience steep, fluctuating temperature and chemical gradients. The functional capacities of communities inhabiting this dynamic habitat are largely unknown. Here, we reconstructed 551 genomes from hydrothermally influenced, and nearby cold sediments belonging to 56 phyla (40 uncultured). These genomes comprise 22 unique lineages, including five new candidate phyla. In contrast to findings from cold hydrocarbon seeps, hydrothermal-associated communities are more diverse and archaea dominate over bacteria. Genome-based metabolic inferences provide first insights into the ecological niches of these uncultured microbes, including methane cycling in new Crenarchaeota and alkane utilization in ANME-1. These communities are shaped by a high biodiversity, partitioning among nitrogen and sulfur pathways and redundancy in core carbon-processing pathways. The dynamic sediments select for distinctive microbial communities that stand out by expansive biodiversity, and open up new physiological perspectives into hydrothermal ecosystem function. 
    more » « less
  • Citation Formats
  • MLA
  • APA
  • Chicago
  • BibTeX
  • Save / Share this Record
  • Send to Email