Applied Microbiology and Biotechnology


Publications (188)

Ethylmalonyl-CoA pathway involved in polyhydroxyvalerate synthesis in Candidatus Contendobacter

Citation
Zhao et al. (2022). AMB Express 12 (1)
Names
Ca. Contendobacter
Subjects
Applied Microbiology and Biotechnology Biophysics
Abstract
AbstractHere a stable glycogen accumulating organisms (GAOs) system was operated by anaerobic–aerobic mode in the sequencing batch reactor. We focused on the metabolic mechanisms of PHAs storage from GAOs. Our system showed the classic characteristic of glycogen accumulating metabolism (GAM). Glycogen consumption was followed by acetic acid uptake to synthesize poly-β-hydroxyalkanoates (PHAs) during the anaerobic period, and glycogen was synthesized by PHAs degradation in the aerobic stage. Microbial community structure indicated that Candidatus Contendobacter was the most prevalent GAOs. We found that the ethylmalonyl-CoA (EMC) pathway was the crucial pathway supplying the core substance propionyl-CoA for poly-β-hydroxyvalerate (PHV) synthesis in Candidatus Contendobacter. All genes in EMC pathway were mainly located in Candidatus Contendobacter by gene source analysis. The key genes expression of EMC pathway increased with Candidatus Contendobacter enrichment, further validating that propionyl-CoA was synthesized by Candidatus Contendobacter predominantly via EMC pathway. Our work revealed the novel mechanisms underlying PHV synthesis through EMC pathway and further improved the intercellular storage metabolism of GAOs.

SeqCode: a nomenclatural code for prokaryotes described from sequence data

Citation
Hedlund et al. (2022). Nature Microbiology
Names
“Kryptoniales” “Kryptoniia” “Kryptoniaceae” “Kryptonium mobile”
Subjects
Applied Microbiology and Biotechnology Cell Biology Genetics Immunology Microbiology Microbiology (medical)
Abstract
AbstractMost prokaryotes are not available as pure cultures and therefore ineligible for naming under the rules and recommendations of the International Code of Nomenclature of Prokaryotes (ICNP). Here we summarize the development of the SeqCode, a code of nomenclature under which genome sequences serve as nomenclatural types. This code enables valid publication of names of prokaryotes based upon isolate genome, metagenome-assembled genome or single-amplified genome sequences. Otherwise, it is similar to the ICNP with regard to the formation of names and rules of priority. It operates through the SeqCode Registry (https://seqco.de/), a registration portal through which names and nomenclatural types are registered, validated and linked to metadata. We describe the two paths currently available within SeqCode to register and validate names, including Candidatus names, and provide examples for both. Recommendations on minimal standards for DNA sequences are provided. Thus, the SeqCode provides a reproducible and objective framework for the nomenclature of all prokaryotes regardless of cultivability and facilitates communication across microbiological disciplines.

A closed Candidatus Odinarchaeum chromosome exposes Asgard archaeal viruses

Citation
Tamarit et al. (2022). Nature Microbiology 7 (7)
Names
Ca. Odinarchaeum yellowstonii
Subjects
Applied Microbiology and Biotechnology Cell Biology Genetics Immunology Microbiology Microbiology (medical)
Abstract
AbstractAsgard archaea have recently been identified as the closest archaeal relatives of eukaryotes. Their ecology, and particularly their virome, remain enigmatic. We reassembled and closed the chromosome of Candidatus Odinarchaeum yellowstonii LCB_4, through long-range PCR, revealing CRISPR spacers targeting viral contigs. We found related viruses in the genomes of diverse prokaryotes from geothermal environments, including other Asgard archaea. These viruses open research avenues into the ecology and evolution of Asgard archaea.

Dehalogenation of Chlorinated Ethenes to Ethene by a Novel Isolate, “ <i>Candidatus</i> Dehalogenimonas etheniformans”

Citation
Chen et al. (2022). Applied and Environmental Microbiology 88 (12)
Names
Ca. Dehalogenimonas etheniformans
Subjects
Applied Microbiology and Biotechnology Biotechnology Ecology Food Science
Abstract
Chlorinated ethenes are risk drivers at many contaminated sites, and current bioremediation efforts focus on organohalide-respiring Dehalococcoides mccartyi strains to achieve detoxification. We isolated and characterized the first non- Dehalococcoides bacterium, “ Candidatus Dehalogenimonas etheniformans” strain GP, capable of metabolic reductive dechlorination of TCE, all DCE isomers, and VC to environmentally benign ethene.

<i>Methanosaeta</i> and “ <i>Candidatus</i> Velamenicoccus archaeovorus”

Citation
Kizina et al. (2022). Applied and Environmental Microbiology 88 (7)
Names
Ca. Velamenicoccus archaeovorus
Subjects
Applied Microbiology and Biotechnology Biotechnology Ecology Food Science
Abstract
Epibiotic bacteria are known to live on and off bacterial cells. Here, we describe the ultramicrobacterial anaerobic epibiont OP3 LiM living on Archaea and Bacteria .

The “Other” <i>Rickettsiales</i> : an Overview of the Family “ <i>Candidatus</i> Midichloriaceae”

Citation
Giannotti et al. (2022). Applied and Environmental Microbiology 88 (6)
Names
Ca. Midichloriaceae
Subjects
Applied Microbiology and Biotechnology Biotechnology Ecology Food Science
Abstract
Among endosymbiotic bacterial lineages, few are as intensely studied as Rickettsiales , which include the causative agents of spotted fever, typhus, and anaplasmosis. However, an important subgroup called “ Candidatus Midichloriaceae” receives little attention despite accounting for a third of the diversity of Rickettsiales and harboring a wide range of bacteria with unique features, like the ability to infect mitochondria.

Candidatus Thiovulum sp. strain imperiosus: the largest free-living Epsilonproteobacteraeota Thiovulum strain lives in a marine mangrove environment

Citation
Sylvestre et al. (2022). Canadian Journal of Microbiology 68 (1)
Names
Ca. Thiovulum
Subjects
Applied Microbiology and Biotechnology General Medicine Genetics Immunology Microbiology Molecular Biology
Abstract
A large (47.75 ± 3.56 µm in diameter) Thiovulum bacterial strain forming white veils is described from a marine mangrove ecosystem. High sulfide concentrations (up to 8 mM of H2S) were measured on sunken organic matter (wood/bone debris) under laboratory conditions. This sulfur-oxidizing bacterium colonized the organic matter, forming a white veil. According to conventional scanning electron microscope (SEM) observations, bacterial cells are ovoid and slightly motile by numerous small flagella present on the cell surface. Large intracytoplasmic internal sulfur granules were observed, suggesting a sulfidic-based metabolism. Observations were confirmed by elemental sulfur distribution detected by energy-dispersive X-ray spectroscopy (EDXS) analysis using an environmental scanning electron microscope (ESEM) on non-dehydrated samples. Phylogenetic analysis of the partial sequence of 16S rDNA obtained from purified fractions of this Epsilonproteobacteraeota strain indicates that this bacterium belongs to the Thiovulaceae cluster and could be one of the largest Thiovulum ever described. We propose to name this species Candidatus Thiovulum sp. strain imperiosus.