Dataset Information

Characterization of a thaumarchaeal symbiont that drives incomplete nitrification in the tropical sponge Ianthella basta

ABSTRACT: Marine sponges represent one of the few eukaryotic groups that ubiquitously harbor symbiotic members of the Thaumarchaeota, which are important chemoautotrophic ammonia-oxidizers in many environments. However in most studies, direct demonstration of ammonia-oxidation by these archaea within sponges is lacking, and little is known about sponge-specific adaptations of archaeal ammonia oxidizers (AOA). In this study, we characterized the thaumarchaeal symbiont of the marine sponge Ianthella basta using metaproteogenomics, fluorescence in situ hybridization, qPCR and direct isotope-based functional assays. We demonstrate that the I. basta symbiont is not closely related to other genomically sequenced sponge AOA and is a member of a new genus. “Candidatus Nitrosospongia bastadiensis” is an abundant symbiont that is solely responsible for nitrite formation from ammonia in I. basta that surprisingly does not harbor nitrite-oxidizing microbes. Consistently, Ca N. bastadiensis encodes and expresses the genetic repertoire required for chemolithoautotrophic ammonia oxidation. Furthermore, we show that this AOA is equipped with an expanded set of extracellular subtilisin-like proteases, a metalloprotease unique among archaea, as well as a putative branched-chain amino acid ABC transporter. This repertoire is strongly indicative of a mixotrophic lifestyle and is (with slight variations) also found in other sponge-associated, but not in free-living AOA. We predict that this feature as well as an expanded and unique set of secreted serpins (protease inhibitors), a unique array of eukaryotic-like proteins, and a DNA-phosporothioation system likely involved in defense against foreign DNA, represent important adaptations of AOA to life within these ancient filter-feeding animals.

INSTRUMENT(S): LTQ Orbitrap Velos

ORGANISM(S): Archaea Bacteria Ianthella Basta

SUBMITTER: Stephanie Markert

LAB HEAD: Stephanie Markert

PROVIDER: PXD012484 | Pride | 2019-11-13

REPOSITORIES: Pride

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			Action	DRS
	130328_V2_P6_CH_StMsponge1_02.raw	Raw
	130328_V2_P6_CH_StMsponge1_03.raw	Raw
	130328_V2_P6_CH_StMsponge1_04.raw	Raw
	130328_V2_P6_CH_StMsponge1_05.raw	Raw
	130328_V2_P6_CH_StMsponge1_06.raw	Raw

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Characterization of a thaumarchaeal symbiont that drives incomplete nitrification in the tropical sponge Ianthella basta.

Moeller Florian U FU Webster Nicole S NS Herbold Craig W CW Behnam Faris F Domman Daryl D Albertsen Mads M Mooshammer Maria M Markert Stephanie S Turaev Dmitrij D Becher Dörte D Rattei Thomas T Schweder Thomas T Richter Andreas A Watzka Margarete M Nielsen Per Halkjaer PH Wagner Michael M

Environmental microbiology 20190725 10

Marine sponges represent one of the few eukaryotic groups that frequently harbour symbiotic members of the Thaumarchaeota, which are important chemoautotrophic ammonia-oxidizers in many environments. However, in most studies, direct demonstration of ammonia-oxidation by these archaea within sponges is lacking, and little is known about sponge-specific adaptations of ammonia-oxidizing archaea (AOA). Here, we characterized the thaumarchaeal symbiont of the marine sponge Ianthella basta using metap ...[more]

PMID: 31271506

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