Genome-Enabled Insights into the Ecophysiology of the Comammox Bacterium “<italic toggle="yes">Candidatus</italic> Nitrospira nitrosa”
ABSTRACT The recently discovered comammox bacteria have the potential to completely oxidize ammonia to nitrate. These microorganisms are part of the Nitrospira genus and are present in a variety of environments, including biological nutrient removal (BNR) systems. However, the physiological traits w...
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| Format: | Article |
| Language: | English |
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American Society for Microbiology
2017-10-01
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| Series: | mSystems |
| Subjects: | |
| Online Access: | https://journals.asm.org/doi/10.1128/mSystems.00059-17 |
| _version_ | 1818855685375393792 |
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| author | Pamela Y. Camejo Jorge Santo Domingo Katherine D. McMahon Daniel R. Noguera |
| author_facet | Pamela Y. Camejo Jorge Santo Domingo Katherine D. McMahon Daniel R. Noguera |
| author_sort | Pamela Y. Camejo |
| collection | DOAJ |
| description | ABSTRACT The recently discovered comammox bacteria have the potential to completely oxidize ammonia to nitrate. These microorganisms are part of the Nitrospira genus and are present in a variety of environments, including biological nutrient removal (BNR) systems. However, the physiological traits within and between comammox and nitrite-oxidizing bacterium (NOB)-like Nitrospira species have not been analyzed in these ecosystems. In this study, we identified Nitrospira strains dominating the nitrifying community of a sequencing batch reactor (SBR) performing BNR under microaerobic conditions. We recovered metagenome-derived draft genomes from two Nitrospira strains: (i) Nitrospira sp. strain UW-LDO-01, a comammox-like organism classified as “Candidatus Nitrospira nitrosa,” and (ii) Nitrospira sp. strain UW-LDO-02, a nitrite-oxidizing strain belonging to the Nitrospira defluvii species. A comparative genomic analysis of these strains with other Nitrospira-like genomes identified genomic differences in “Ca. Nitrospira nitrosa” mainly attributed to each strain’s niche adaptation. Traits associated with energy metabolism also differentiate comammox from NOB-like genomes. We also identified several transcriptionally regulated adaptive traits, including stress tolerance, biofilm formation, and microaerobic metabolism, which might explain survival of Nitrospira under multiple environmental conditions. Overall, our analysis expanded our understanding of the genetic functional features of “Ca. Nitrospira nitrosa” and identified genomic traits that further illuminate the phylogenetic diversity and metabolic plasticity of the Nitrospira genus. IMPORTANCE Nitrospira-like bacteria are among the most diverse and widespread nitrifiers in natural ecosystems and the dominant nitrite oxidizers in wastewater treatment plants (WWTPs). The recent discovery of comammox-like Nitrospira strains, capable of complete oxidation of ammonia to nitrate, raises new questions about specific traits responsible for the functional versatility and adaptation of this genus to a variety of environments. The availability of new Nitrospira genome sequences from both nitrite-oxidizing and comammox bacteria offers a way to analyze traits in different Nitrospira functional groups. Our comparative genomics analysis provided new insights into the adaptation of Nitrospira strains to specific lifestyles and environmental niches. Author Video: An author video summary of this article is available. |
| first_indexed | 2024-12-19T08:12:32Z |
| format | Article |
| id | doaj.art-fa32f4af716548968af59121f5ce4077 |
| institution | Directory Open Access Journal |
| issn | 2379-5077 |
| language | English |
| last_indexed | 2024-12-19T08:12:32Z |
| publishDate | 2017-10-01 |
| publisher | American Society for Microbiology |
| record_format | Article |
| series | mSystems |
| spelling | doaj.art-fa32f4af716548968af59121f5ce40772022-12-21T20:29:36ZengAmerican Society for MicrobiologymSystems2379-50772017-10-012510.1128/mSystems.00059-17Genome-Enabled Insights into the Ecophysiology of the Comammox Bacterium “<italic toggle="yes">Candidatus</italic> Nitrospira nitrosa”Pamela Y. Camejo0Jorge Santo Domingo1Katherine D. McMahon2Daniel R. Noguera3Department of Civil and Environmental Engineering, University of Wisconsin—Madison, Madison, Wisconsin, USAEnvironmental Protection Agency, Cincinnati, Ohio, USADepartment of Civil and Environmental Engineering, University of Wisconsin—Madison, Madison, Wisconsin, USADepartment of Civil and Environmental Engineering, University of Wisconsin—Madison, Madison, Wisconsin, USAABSTRACT The recently discovered comammox bacteria have the potential to completely oxidize ammonia to nitrate. These microorganisms are part of the Nitrospira genus and are present in a variety of environments, including biological nutrient removal (BNR) systems. However, the physiological traits within and between comammox and nitrite-oxidizing bacterium (NOB)-like Nitrospira species have not been analyzed in these ecosystems. In this study, we identified Nitrospira strains dominating the nitrifying community of a sequencing batch reactor (SBR) performing BNR under microaerobic conditions. We recovered metagenome-derived draft genomes from two Nitrospira strains: (i) Nitrospira sp. strain UW-LDO-01, a comammox-like organism classified as “Candidatus Nitrospira nitrosa,” and (ii) Nitrospira sp. strain UW-LDO-02, a nitrite-oxidizing strain belonging to the Nitrospira defluvii species. A comparative genomic analysis of these strains with other Nitrospira-like genomes identified genomic differences in “Ca. Nitrospira nitrosa” mainly attributed to each strain’s niche adaptation. Traits associated with energy metabolism also differentiate comammox from NOB-like genomes. We also identified several transcriptionally regulated adaptive traits, including stress tolerance, biofilm formation, and microaerobic metabolism, which might explain survival of Nitrospira under multiple environmental conditions. Overall, our analysis expanded our understanding of the genetic functional features of “Ca. Nitrospira nitrosa” and identified genomic traits that further illuminate the phylogenetic diversity and metabolic plasticity of the Nitrospira genus. IMPORTANCE Nitrospira-like bacteria are among the most diverse and widespread nitrifiers in natural ecosystems and the dominant nitrite oxidizers in wastewater treatment plants (WWTPs). The recent discovery of comammox-like Nitrospira strains, capable of complete oxidation of ammonia to nitrate, raises new questions about specific traits responsible for the functional versatility and adaptation of this genus to a variety of environments. The availability of new Nitrospira genome sequences from both nitrite-oxidizing and comammox bacteria offers a way to analyze traits in different Nitrospira functional groups. Our comparative genomics analysis provided new insights into the adaptation of Nitrospira strains to specific lifestyles and environmental niches. Author Video: An author video summary of this article is available.https://journals.asm.org/doi/10.1128/mSystems.00059-17“Ca. Nitrospira nitrosa”comammoxNOBNitrospirametagenomics |
| spellingShingle | Pamela Y. Camejo Jorge Santo Domingo Katherine D. McMahon Daniel R. Noguera Genome-Enabled Insights into the Ecophysiology of the Comammox Bacterium “<italic toggle="yes">Candidatus</italic> Nitrospira nitrosa” mSystems “Ca. Nitrospira nitrosa” comammox NOB Nitrospira metagenomics |
| title | Genome-Enabled Insights into the Ecophysiology of the Comammox Bacterium “<italic toggle="yes">Candidatus</italic> Nitrospira nitrosa” |
| title_full | Genome-Enabled Insights into the Ecophysiology of the Comammox Bacterium “<italic toggle="yes">Candidatus</italic> Nitrospira nitrosa” |
| title_fullStr | Genome-Enabled Insights into the Ecophysiology of the Comammox Bacterium “<italic toggle="yes">Candidatus</italic> Nitrospira nitrosa” |
| title_full_unstemmed | Genome-Enabled Insights into the Ecophysiology of the Comammox Bacterium “<italic toggle="yes">Candidatus</italic> Nitrospira nitrosa” |
| title_short | Genome-Enabled Insights into the Ecophysiology of the Comammox Bacterium “<italic toggle="yes">Candidatus</italic> Nitrospira nitrosa” |
| title_sort | genome enabled insights into the ecophysiology of the comammox bacterium italic toggle yes candidatus italic nitrospira nitrosa |
| topic | “Ca. Nitrospira nitrosa” comammox NOB Nitrospira metagenomics |
| url | https://journals.asm.org/doi/10.1128/mSystems.00059-17 |
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