Limits...
Identifying Potential Mechanisms Enabling Acidophily in the Ammonia-Oxidizing Archaeon "Candidatus Nitrosotalea devanaterra".

Lehtovirta-Morley LE, Sayavedra-Soto LA, Gallois N, Schouten S, Stein LY, Prosser JI, Nicol GW - Appl. Environ. Microbiol. (2016)

Bottom Line: Instead, the genome indicates that "Ca Nitrosotalea devanaterra" contains genes encoding both a predicted high-affinity substrate acquisition system and potential pH homeostasis mechanisms absent in neutrophilic AOA.Analysis of mRNA revealed that candidate genes encoding the proposed homeostasis mechanisms were all expressed during acidophilic growth, and lipid profiling by high-performance liquid chromatography-mass spectrometry (HPLC-MS) demonstrated that the membrane lipids of "Ca Nitrosotalea devanaterra" were not dominated by crenarchaeol, as found in neutrophilic AOA.This study for the first time describes a genome of an obligately acidophilic ammonia oxidizer and identifies potential mechanisms enabling this unique phenotype for future biochemical characterization.

View Article: PubMed Central - PubMed

Affiliation: Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, United Kingdom l.lehtovirta@abdn.ac.uk.

No MeSH data available.


Related in: MedlinePlus

Ammonium transporters of “Ca. Nitrosotalea devanaterra.” (A) Maximum-likelihood phylogeny of Amt/Rh transporters. The transported substrate (ammonia versus ammonium) has been validated in organisms highlighted with red and blue circles. Red, ammonium (NH4+); blue, ammonia (NH3). Circles at nodes highlight the level of bootstrap support, and the scale bar represents 0.5 change per amino acid position. (B) Conservation of the cation binding site in Amt/Rh sequences. (C) Transport mechanisms of Amt/Rh transporters previously reported in the literature (see Table S9 in the supplemental material).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4836417&req=5

Figure 5: Ammonium transporters of “Ca. Nitrosotalea devanaterra.” (A) Maximum-likelihood phylogeny of Amt/Rh transporters. The transported substrate (ammonia versus ammonium) has been validated in organisms highlighted with red and blue circles. Red, ammonium (NH4+); blue, ammonia (NH3). Circles at nodes highlight the level of bootstrap support, and the scale bar represents 0.5 change per amino acid position. (B) Conservation of the cation binding site in Amt/Rh sequences. (C) Transport mechanisms of Amt/Rh transporters previously reported in the literature (see Table S9 in the supplemental material).

Mentions: Ammonium transporters of AOA and AOB are distantly related and belong to two functionally and phylogenetically distinct families: Amt and Rh, respectively (67). The substrate preferences (NH3 versus NH4+) often differ between Amt and Rh types (68, 69). Rh transporters are thought to perform bidirectional diffusion equilibrating NH3 (70), and Amt transporters are energy dependent (71) (Fig. 5C). Furthermore, Amt transporters function better or equally well at acidic pH, whereas Rh transporters favor neutral/high pH (68, 72). Although archaeal ammonium transporters were extensively reviewed recently (67), the transported species (NH3 versus NH4+) of Amt/Rh transporters remains uncertain, and no hypothesis has been put forward for the preferred substrate.


Identifying Potential Mechanisms Enabling Acidophily in the Ammonia-Oxidizing Archaeon "Candidatus Nitrosotalea devanaterra".

Lehtovirta-Morley LE, Sayavedra-Soto LA, Gallois N, Schouten S, Stein LY, Prosser JI, Nicol GW - Appl. Environ. Microbiol. (2016)

Ammonium transporters of “Ca. Nitrosotalea devanaterra.” (A) Maximum-likelihood phylogeny of Amt/Rh transporters. The transported substrate (ammonia versus ammonium) has been validated in organisms highlighted with red and blue circles. Red, ammonium (NH4+); blue, ammonia (NH3). Circles at nodes highlight the level of bootstrap support, and the scale bar represents 0.5 change per amino acid position. (B) Conservation of the cation binding site in Amt/Rh sequences. (C) Transport mechanisms of Amt/Rh transporters previously reported in the literature (see Table S9 in the supplemental material).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4836417&req=5

Figure 5: Ammonium transporters of “Ca. Nitrosotalea devanaterra.” (A) Maximum-likelihood phylogeny of Amt/Rh transporters. The transported substrate (ammonia versus ammonium) has been validated in organisms highlighted with red and blue circles. Red, ammonium (NH4+); blue, ammonia (NH3). Circles at nodes highlight the level of bootstrap support, and the scale bar represents 0.5 change per amino acid position. (B) Conservation of the cation binding site in Amt/Rh sequences. (C) Transport mechanisms of Amt/Rh transporters previously reported in the literature (see Table S9 in the supplemental material).
Mentions: Ammonium transporters of AOA and AOB are distantly related and belong to two functionally and phylogenetically distinct families: Amt and Rh, respectively (67). The substrate preferences (NH3 versus NH4+) often differ between Amt and Rh types (68, 69). Rh transporters are thought to perform bidirectional diffusion equilibrating NH3 (70), and Amt transporters are energy dependent (71) (Fig. 5C). Furthermore, Amt transporters function better or equally well at acidic pH, whereas Rh transporters favor neutral/high pH (68, 72). Although archaeal ammonium transporters were extensively reviewed recently (67), the transported species (NH3 versus NH4+) of Amt/Rh transporters remains uncertain, and no hypothesis has been put forward for the preferred substrate.

Bottom Line: Instead, the genome indicates that "Ca Nitrosotalea devanaterra" contains genes encoding both a predicted high-affinity substrate acquisition system and potential pH homeostasis mechanisms absent in neutrophilic AOA.Analysis of mRNA revealed that candidate genes encoding the proposed homeostasis mechanisms were all expressed during acidophilic growth, and lipid profiling by high-performance liquid chromatography-mass spectrometry (HPLC-MS) demonstrated that the membrane lipids of "Ca Nitrosotalea devanaterra" were not dominated by crenarchaeol, as found in neutrophilic AOA.This study for the first time describes a genome of an obligately acidophilic ammonia oxidizer and identifies potential mechanisms enabling this unique phenotype for future biochemical characterization.

View Article: PubMed Central - PubMed

Affiliation: Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, United Kingdom l.lehtovirta@abdn.ac.uk.

No MeSH data available.


Related in: MedlinePlus