Genetics


Publications (271)

Deciphering Symbiotic Interactions of “ Candidatus Aenigmarchaeota” with Inferred Horizontal Gene Transfers and Co-occurrence Networks

Citation
Li et al. (2021). mSystems 6 (4)
Names
Ca. Aenigmarchaeota
Subjects
Biochemistry Computer Science Applications Ecology, Evolution, Behavior and Systematics Genetics Microbiology Modeling and Simulation Modelling and Simulation Molecular Biology Physiology
Abstract
Recent advances in sequencing technology promoted the blowout discovery of super tiny microbes in the Diapherotrites , Parvarchaeota , Aenigmarchaeota , Nanoarchaeota , and Nanohaloarchaeota (DPANN) superphylum. However, the unculturable properties of the majority of microbes impeded our investigation of their behavior and symbiotic lifestyle in the corresponding community.

Sequence specific integration by the family 1 casposase from Candidatus Nitrosopumilus koreensis AR1

Citation
Wang et al. (2021). Nucleic Acids Research 49 (17)
Names
Ca. Nitrosopumilus koreensis
Subjects
Genetics
Abstract
Abstract Casposase, a homolog of Cas1 integrase, is encoded by a superfamily of mobile genetic elements known as casposons. While family 2 casposase has been well documented in both function and structure, little is known about the other three casposase families. Here, we studied the family 1 casposase lacking the helix-turn-helix (HTH) domain from Candidatus Nitrosopumilus koreensis AR1 (Ca. N. koreensis). The determinants for integration by Ca. N. koreensis casposase were extensively investigated, and it was found that a 13-bp target site duplication (TSD) sequence, a minimal 3-bp leader and three different nucleotides of the TSD sequences are indispensable for target specific integration. Significantly, the casposase can site-specifically integrate a broad range of terminal inverted repeat (TIR)-derived oligonucleotides ranging from 7-nt to ∼4000-bp, and various oligonucleotides lacking the 5′-TTCTA-3′ motif at the 3′ end of TIR sequence can be integrated efficiently. Furthermore, similar to some Cas1 homologs, the casposase utilizes a 5′-ATAA-3′ motif in the TSD as a molecular ruler to dictate nucleophilic attack at 9-bp downstream of the end of the ruler during the spacer-side integration. By characterizing the family 1 Ca. N. koreensis casposase, we have extended our understanding on mechanistic similarities and evolutionary connections between casposons and the adaptation elements of CRISPR-Cas immunity.

‘Candidatus Chloroploca mongolica’ sp. nov. a new mesophilic filamentous anoxygenic phototrophic bacterium

Citation
Bryantseva et al. (2021). FEMS Microbiology Letters 368 (16)
Names
Ca. Chloroploca mongolica Ca. Chloroploca asiatica Ca. Chloroploca
Subjects
Genetics Microbiology Molecular Biology
Abstract
ABSTRACT A mesophilic filamentous anoxygenic phototrophic bacterium, designated M50-1, was isolated from a microbial mat of the Chukhyn Nur soda lake (northeastern Mongolia) with salinity of 5−14 g/L and pH 8.0−9.3. The organism is a strictly anaerobic phototrophic bacterium, which required sulfide for phototrophic growth. The cells formed short undulate trichomes surrounded by a thin sheath and containing gas vesicles. Motility of the trichomes was not observed. The cells contained chlorosomes. The antenna pigments were bacteriochlorophyll d and β- and γ-carotenes. Analysis of the genome assembled from the metagenome of the enrichment culture revealed all the enzymes of the 3-hydroxypropionate bi-cycle for autotrophic CO2 assimilation. The genome also contained the genes encoding a type IV sulfide:quinone oxidoreductase (sqrX). The organism had no nifHDBK genes, encoding the proteins of the nitrogenase complex responsible for dinitrogen fixation. The DNA G + C content was 58.6%. The values for in silico DNA‒DNA hybridization and average nucleotide identity between M50-1 and a closely related bacterium ‘Ca. Chloroploca asiatica’ B7-9 containing bacteriochlorophyll c were 53.4% and 94.0%, respectively, which corresponds to interspecies differences. Classification of the filamentous anoxygenic phototrophic bacterium M50-1 as a new ‘Ca. Chloroploca’ species was proposed, with the species name ‘Candidatus Chloroploca mongolica’ sp. nov.

Complete Genome Sequence of Rhynchophorus ferrugineus Endocytobiont “ Candidatus Nardonella dryophthoridicola” Strain NardRF

Citation
Chouaia et al. (2021). Microbiology Resource Announcements 10 (26)
Names
Ca. Nardonella dryophthoridicola
Subjects
Genetics Immunology and Microbiology (miscellaneous) Molecular Biology
Abstract
We report the complete genome sequence and annotation of “ Candidatus Nardonella dryophthoridicola” strain NardRF, obtained by sequencing its host bacteriome, Rhynchophorus ferrugineus , using Oxford Nanopore technology.

Genomic insights into diverse bacterial taxa that degrade extracellular DNA in marine sediments

Citation
Wasmund et al. (2021). Nature Microbiology 6 (7)
Names
Ca. Izemoplasmatales Ca. Izemoplasma Ca. Izemoplasma acidinucleici
Subjects
Applied Microbiology and Biotechnology Cell Biology Genetics Immunology Microbiology Microbiology (medical)
Abstract
AbstractExtracellular DNA is a major macromolecule in global element cycles, and is a particularly crucial phosphorus, nitrogen and carbon source for microorganisms in the seafloor. Nevertheless, the identities, ecophysiology and genetic features of DNA-foraging microorganisms in marine sediments are largely unknown. Here, we combined microcosm experiments, DNA stable isotope probing (SIP), single-cell SIP using nano-scale secondary isotope mass spectrometry (NanoSIMS) and genome-centric metagenomics to study microbial catabolism of DNA and its subcomponents in marine sediments. 13C-DNA added to sediment microcosms was largely degraded within 10 d and mineralized to 13CO2. SIP probing of DNA revealed diverse ‘Candidatus Izemoplasma’, Lutibacter, Shewanella and Fusibacteraceae incorporated DNA-derived 13C-carbon. NanoSIMS confirmed incorporation of 13C into individual bacterial cells of Fusibacteraceae sorted from microcosms. Genomes of the 13C-labelled taxa all encoded enzymatic repertoires for catabolism of DNA or subcomponents of DNA. Comparative genomics indicated that diverse ‘Candidatus Izemoplasmatales’ (former Tenericutes) are exceptional because they encode multiple (up to five) predicted extracellular nucleases and are probably specialized DNA-degraders. Analyses of additional sediment metagenomes revealed extracellular nuclease genes are prevalent among Bacteroidota at diverse sites. Together, our results reveal the identities and functional properties of microorganisms that may contribute to the key ecosystem function of degrading and recycling DNA in the seabed.

Complete Genome Sequence of Strain JB001, a Member of Saccharibacteria Clade G6 (“ Candidatus Nanogingivalaceae”)

Citation
Baker (2021). Microbiology Resource Announcements 10 (23)
Names
Ca. Nanogingivalaceae
Subjects
Genetics Immunology and Microbiology (miscellaneous) Molecular Biology
Abstract
At least 6 highly diverse clades of Saccharibacteria inhabit the human oral cavity. However, all oral Saccharibacteria strains with currently available complete genome sequences or cultured isolates belong to clade G1, leaving clades G2 through G6 poorly understood. Here, a complete genome sequence of JB001, a clade G6 (“ Candidatus Nanogingivalaceae”) Saccharibacteria strain, is reported.

Complete Genome Sequence of the Endosymbiotic Bacterium “ Candidatus Riesia pediculicola”

Citation
Park et al. (2021). Microbiology Resource Announcements 10 (18)
Names
Ca. Riesia pediculicola
Subjects
Genetics Immunology and Microbiology (miscellaneous) Molecular Biology
Abstract
Human head and body lice host the obligate endosymbiotic bacterium “ Candidatus Riesia pediculicola.” In this announcement, we describe the complete genome sequence of a “ Ca. Riesia pediculicola” strain isolated from the human head louse, Pediculus humanus subsp. capitis . The inter- and intraspecific variations of endosymbiont genomes were investigated, and this strain was found to display high-level variations in its genome.

Production and Excretion of Polyamines To Tolerate High Ammonia, a Case Study on Soil Ammonia-Oxidizing Archaeon “ Candidatus Nitrosocosmicus agrestis”

Citation
Liu et al. (2021). mSystems 6 (1)
Names
Ca. Nitrosocosmicus agrestis Ca. Nitrosocosmicus
Subjects
Biochemistry Computer Science Applications Ecology, Evolution, Behavior and Systematics Genetics Microbiology Modelling and Simulation Molecular Biology Physiology
Abstract
Ammonia tolerance of AOA is usually much lower than that of the AOB, which makes the AOB rather than AOA a predominant ammonia oxidizer in agricultural soils, contributing to global N 2 O emission. Recently, some AOA species from the genus “ Ca. Nitrosocosmicus” were also found to have high ammonia tolerance.