this with annotations you find in gene/protein databases, but these can be outdated or inaccurate. Falcon Edison Scientific Literature 35 citations 1 artifacts 2026-06-03T10:12:48.979850

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Research report: functional annotation of mxcQ (UniProt C5ASP2) in Methylorubrum extorquens AM1

Executive summary

The gene mxcQ in Methylorubrum extorquens AM1 (formerly Methylobacterium extorquens AM1) encodes the sensor histidine kinase component of the MxcQE two-component system (TCS), which is repeatedly implicated in regulating methanol oxidation gene expression—particularly the Ca-dependent methanol dehydrogenase (MDH) system (mxa operon/cluster) and the lanthanide-dependent MDH system (xox1 operon/cluster)—as part of the “lanthanide switch” (Ln-switch). The best-supported organism-specific role for MxcQ is thus signal transduction controlling MDH gene expression in response to lanthanide availability (directly or indirectly), rather than a demonstrated NreB-like oxygen sensor controlling nitrate respiration. (vu2016lanthanidedependentregulationof pages 6-9, vu2016lanthanidedependentregulationof pages 31-40, pastawan2020biologicalfunctionof pages 6-8)

UniProt’s description of C5ASP2 as “oxygen sensor histidine kinase NreB” should be treated as homology-based annotation in this context: the canonical NreB proteins with clear oxygen-sensing Fe–S chemistry are experimentally characterized mainly in staphylococci and regulate anaerobic nitrate respiration genes via the NreABC system, which differs from the AM1 methylotrophy/Ln-switch regulatory module supported in the retrieved AM1 literature. (nilkens2013thenreabcsystem pages 80-84, nilkens2013thenreabcsystem pages 6-9, hsueh2013feocfromklebsiella pages 9-9)

1) Key concepts and definitions (current understanding)

Two-component systems (TCS)

Two-component systems are bacterial signal transduction modules typically comprising (i) a sensor histidine kinase (HK) that autophosphorylates on a conserved histidine and (ii) a response regulator (RR) that receives the phosphoryl group on a conserved aspartate to regulate gene expression or other cellular outputs. (selvamani2020engineeringofrecombinant pages 1-3)

The lanthanide switch (Ln-switch)

In many methylotrophs, including AM1, lanthanides (Ln) shift methanol oxidation away from the classical Ca-dependent MDH (MxaFI) toward Ln-dependent MDHs (XoxF). This regulated switching of mxaFI versus xox transcription in response to Ln availability is termed the “Ln switch.” (pastawan2020biologicalfunctionof pages 6-8, vu2016lanthanidedependentregulationof pages 1-6)

A commonly discussed model posits that under Ln-limiting conditions, apo-XoxF (periplasmic, Ln-free form) may act as (or contribute to) the sensing mechanism by interacting with the sensor kinases MxcQ and/or MxbD, activating mxa and repressing xox1. When Ln are present, XoxF becomes Ln-bound/active and no longer drives that signaling state, yielding mxa repression and xox1 activation. This model is widely cited but remains a hypothesis regarding the direct sensory ligand for MxcQ. (vu2016lanthanidedependentregulationof pages 31-40, pastawan2020biologicalfunctionof pages 6-8)

2) Verified identity of the research target and ambiguity resolution

Verified AM1 identity used in this report

The literature retrieved that explicitly mentions mxcQ/MxcQ in AM1 consistently treats it as part of MxcQE, a TCS involved in methanol oxidation gene regulation, acting together with another TCS (MxbDM) and the RR MxaB in controlling mxa and xox1 transcription. (vu2016lanthanidedependentregulationof pages 6-9, vu2016lanthanidedependentregulationof pages 31-40, pastawan2020biologicalfunctionof pages 6-8)

Potential ambiguity with NreB naming

Canonical NreB proteins (staphylococcal NreABC system) are described as oxygen/redox-responsive histidine kinases that incorporate an oxygen-labile [4Fe–4S] cluster and integrate nitrate sensing through NreA. They regulate genes involved in anaerobic nitrate respiration (e.g., nar/nir/sir gene sets). (nilkens2013thenreabcsystem pages 80-84, nilkens2013thenreabcsystem pages 6-9)

While UniProt labels C5ASP2 as “NreB,” the AM1-specific evidence available here supports MxcQ’s role in the Ln-switch/methylotrophy regulatory network and does not demonstrate Fe–S oxygen sensing or NreABC-style nitrate respiration control in AM1. Therefore, functional annotation for AM1 should prioritize the MxcQ/MxcQE methanol oxidation regulatory role supported by AM1 methylotrophy studies, and treat the NreB name as tentative without direct AM1 experimental validation. (vu2016lanthanidedependentregulationof pages 31-40, nilkens2013thenreabcsystem pages 80-84)

3) Functional role of MxcQ in AM1

3.1 Pathway context: methanol oxidation systems and their regulation

AM1 possesses at least two major MDH systems:
- MxaFI MDH: PQQ-dependent, Ca-dependent; periplasmic methanol oxidation system. (vu2016lanthanidedependentregulationof pages 1-6)
- XoxF MDH: PQQ-dependent, lanthanide-dependent; promoted when Ln are available. (vu2016lanthanidedependentregulationof pages 1-6)

In AM1, transcriptional reporter experiments show that exogenous lanthanides cause differential expression from the mxa and xox1 promoters, with xox1 upregulated and mxa repressed under Ln availability, consistent with Ln-switch behavior. (vu2016lanthanidedependentregulationof pages 1-6)

3.2 Regulatory network membership: MxcQE, MxbDM, and MxaB

AM1 regulation of methanol oxidation genes involves multiple regulators:
- MxcQE (TCS): required for expression of the mxa genes, but it is not resolved in the cited work whether regulation is direct or indirect or what signal(s) MxcQ senses. (vu2016lanthanidedependentregulationof pages 6-9, vu2016lanthanidedependentregulationof pages 31-40)
- MxbDM (TCS): required for expression of the mxa operon and (in the absence of lanthanides) required to repress xox1. (vu2016lanthanidedependentregulationof pages 6-9)
- MxaB (RR): also required for mxa expression (by genetics summarized in later reviews). (pastawan2020biologicalfunctionof pages 6-8)

A review summarizing prior genetics states that MxcE, MxaB, and MxbM are all required for activation of the mxa cluster, while only MxbM is required for repression of xox1. (pastawan2020biologicalfunctionof pages 6-8)

3.3 Hypothesized sensory input: apo-XoxF interaction model

A prominent mechanistic hypothesis is that apo-XoxF (the Ln-free periplasmic protein) may act as a cellular Ln sensor by interacting with MxcQ and/or MxbD, thereby controlling the phosphorylation state/output of MxcQE and/or MxbDM and ultimately controlling mxa/xox transcription. This is explicitly presented as a postulate/hypothesis rather than a direct biochemical demonstration of ligand binding or signal perception by MxcQ. (vu2016lanthanidedependentregulationof pages 31-40, pastawan2020biologicalfunctionof pages 6-8)

4) Domain architecture and localization (evidence-based and inferred)

4.1 Localization: evidence consistent with a membrane-associated HK

A practical biosensor-engineering study describes using the “periplasmic sensor domain” of mxcQ from AM1 fused to the cytoplasmic catalytic domain of EnvZ to create a chimeric sensor kinase in E. coli, consistent with the notion that MxcQ is a membrane-associated HK with a periplasmic sensory region and a cytosolic transmitter/kinase region. (selvamani2020engineeringofrecombinant pages 1-3, selvamani2020engineeringofrecombinant pages 3-5)

This is not a direct AM1 cell-localization assay, but it is consistent with typical topology of many TCS sensor kinases (periplasmic/extracellular sensing + cytosolic phosphotransfer). (selvamani2020engineeringofrecombinant pages 1-3)

4.2 Enzymatic activity class

MxcQ is annotated as a histidine kinase (EC 2.7.13.3 in UniProt). None of the retrieved AM1 papers provides purified MxcQ biochemical autophosphorylation assays; its kinase role is inferred from its designation as the HK partner in the MxcQE TCS and from genetic evidence placing MxcQE in the regulatory cascade. (vu2016lanthanidedependentregulationof pages 6-9, pastawan2020biologicalfunctionof pages 6-8)

5) Recent developments (prioritizing 2023–2024 where available)

5.1 2023: cross-taxa lanthanome study referencing MxcQ/MxcE homology

A 2023 JBC study investigating lanthanide biology in Methylobacillus flagellatus notes that a histidine kinase (Mfla_0817) shows partial homology to MxcQ from AM1, with homology largely limited to the histidine-kinase domains, and that a response regulator homologous to MxcE exists. The study also summarizes that in AM1, MxcQ/MxcE and MxbD/MxbM act together to regulate mxaF and xoxF expression (citing prior work), supporting conservation of the regulatory module concept across methylotrophs even if specific sensing mechanisms differ. (jethro2023lanpepsyisa pages 2-3, jethro2023lanpepsyisa pages 1-2)

5.2 2024: limited direct MxcQ-specific literature retrieved

No 2023–2024 AM1 primary paper directly characterizing MxcQ’s ligand/sensing mechanism or phosphorylation biochemistry was retrieved in this tool run. The most relevant 2024 items retrieved were not AM1 MxcQ-specific mechanistic studies.

6) Current applications and real-world implementations

6.1 Methanol biosensing via MxcQ-derived sensory modules

A concrete implementation is the engineering of methanol-sensing in recombinant E. coli by creating chimeric histidine kinases incorporating sensory regions from AM1 methylotrophy regulators, including MxcQ. The study reports a methanol-responsive output (ompC-driven reporter/GFP), with maximal fluorescence observed at 0.01% methanol for the MxcQ-derived chimera, illustrating that MxcQ contains a sensory module that can be repurposed for synthetic biology sensing applications. (selvamani2020engineeringofrecombinant pages 1-3)

6.2 Lanthanide biotechnology context: biomining/biorecycling and protein-based separation

The AM1 lanthanide-switch literature explicitly frames lanthanide-dependent methylotrophy regulation as relevant to biotechnological use of methylotrophs and to development of alternative strategies for recovery of rare-earth elements. (vu2016lanthanidedependentregulationof pages 1-6)

Additionally, the 2023 identification of a novel lanthanide-binding PepSY-family protein (LanP/lanpepsy) is discussed as being of interest for “applications toward the sustainable purification and separation of rare-earth elements,” illustrating ongoing translation of lanthanide biology into separation/bioprocess concepts; while not directly MxcQ, this is part of the broader lanthanide response context in methylotrophs that intersects with MDH regulation. (jethro2023lanpepsyisa pages 1-2)

7) Expert opinions and authoritative synthesis

A 2016 peer-reviewed AM1 study emphasizes that lanthanide availability can act at very low concentrations and that methylotroph physiology is strongly shaped by lanthanide-responsive regulation of methanol oxidation systems, with implications for cultivation and applications. (vu2016lanthanidedependentregulationof pages 1-6)

A 2020 review synthesizes prior genetic findings into a coherent Ln-switch model in which MxcQ/MxbD sensor kinases and their cognate RRs coordinate activation of mxa and repression of xox1 under Ln limitation, while Ln availability reverses the regulatory state. The review explicitly acknowledges that detailed mechanisms remain largely unknown, which remains an important caveat for functional annotation. (pastawan2020biologicalfunctionof pages 6-8)

8) Relevant statistics and quantitative data (recent studies)

8.1 Lanthanide concentration thresholds for growth and promoter behavior

In AM1, growth and reporter assays show strong lanthanide sensitivity:
- Maximum growth rate and yield are achieved at and above 1 μM La, while concentrations as low as 2.5 nM La allow growth at reduced rate. (vu2016lanthanidedependentregulationof pages 1-6, vu2016lanthanidedependentregulationof pages 9-14)
- Intermediate expression from both mxa and xox1 promoters is observed when 50–100 nM La is added, suggesting a regime in which both systems may be utilized. (vu2016lanthanidedependentregulationof pages 1-6)

8.2 Growth kinetics and MDH activity under lanthanide conditions

Under La-dependent methanol growth conditions (representative examples):
- Doubling times: wild type 5.5 ± 0.2 h; xoxF1 mutant 8.6 ± 0.9 h; xoxF1 xoxF2 mutant 19.1 ± 0.8 h. (vu2016lanthanidedependentregulationof pages 9-14)
- MDH specific activity in cell-free extracts: WT 64 ± 4 (Ca condition) vs 81 ± 3 nmol·min⁻¹·mg⁻¹ (La condition); triple MeDH mutant 9 ± 1 nmol·min⁻¹·mg⁻¹. (vu2016lanthanidedependentregulationof pages 9-14)

8.3 NreB mechanistic residues (comparison only)

For the canonical oxygen sensor histidine kinase NreB (staphylococci), mechanistic statements include:
- Autophosphorylation at H159 and transfer to NreC D53, with a conserved DxxxQ motif adjacent to H159 implicated in kinase/phosphatase behavior; O2 sensitivity is linked to binding of an O2-labile [4Fe–4S]²⁺ cluster under anaerobic conditions. (nilkens2013thenreabcsystem pages 80-84)

9) Comparison to canonical NreB oxygen-sensing histidine kinases (why UniProt’s name may not reflect AM1 function)

Canonical NreB proteins are oxygen/redox sensors that employ O2-labile Fe–S chemistry and regulate nitrate respiration gene expression in response to oxygen and nitrate availability. They function in an NreABC module where NreA is a nitrate-binding GAF protein that modulates NreB phosphorylation activity. (nilkens2013thenreabcsystem pages 80-84, nilkens2013thenreabcsystem pages 6-9)

By contrast, the AM1 literature retrieved here places MxcQ in a methanol oxidation regulatory network governing the Ln-switch, with strong physiological evidence of lanthanide-dependent transcriptional switching between mxa and xox programs but without direct evidence of Fe–S cluster-based oxygen sensing by MxcQ. (vu2016lanthanidedependentregulationof pages 31-40, vu2016lanthanidedependentregulationof pages 1-6)

10) Evidence summary table

The following table consolidates the key evidence, including study dates and URLs.

Entity Organism / system Identity / partners Functional interpretation Inputs / signals discussed Regulated outputs / phenotype Quantitative or mechanistic details Source (year) DOI / URL Evidence
mxcQ / MxcQ (UniProt C5ASP2) Methylorubrum extorquens AM1 (formerly Methylobacterium extorquens AM1) Target protein is encoded by mxcQ; part of the MxcQE two-component system, with MxcE as cognate response regulator; acts in the same regulatory network as MxbDM and MxaB for methanol oxidation gene control Best-supported role in the literature is a regulatory sensor histidine kinase involved in methanol dehydrogenase gene regulation, not a directly characterized oxygen sensor in AM1 Inputs are not directly demonstrated for AM1 MxcQ; literature discusses lanthanide availability and proposes apo-XoxF in the periplasm may interact with MxcQ and/or MxbD as part of the Ln-switch Required within the regulatory cascade controlling mxa expression; network also influences xox1 repression/activation depending on lanthanides Direct biochemical sensing mechanism for AM1 MxcQ remains unresolved in cited literature Vu et al. (2016); Pastawan et al. (2020) https://doi.org/10.1128/JB.00937-15 ; https://doi.org/10.7831/ras.8.0_186 (vu2016lanthanidedependentregulationof pages 6-9, vu2016lanthanidedependentregulationof pages 31-40, pastawan2020biologicalfunctionof pages 6-8)
MxcQE pathway position M. extorquens AM1 MxcQE regulates expression of mxbDM; MxbDM directly regulates the mxa cluster; response regulators MxcE, MxaB, and MxbM are required for activation of the mxa cluster, while MxbM is specifically required for repression of xox1 Places MxcQ upstream in the methanol/lanthanide regulatory hierarchy Methanol oxidation state and lanthanide-dependent switching are the physiological context mxa cluster activation under no-Ln conditions; xox1 repression under no-Ln conditions through the broader network This is a regulatory model synthesized from genetics rather than direct MxcQ biochemistry Pastawan et al. (2020) https://doi.org/10.7831/ras.8.0_186 (pastawan2020biologicalfunctionof pages 6-8)
Ln-switch model involving MxcQ M. extorquens AM1 MxcQ is one of the sensor kinases proposed to receive information from apo-XoxF; MxbD may play an analogous or complementary role Inferred sensor role in lanthanide-responsive switching between Ca-dependent and Ln-dependent methanol dehydrogenases Proposed signal is apo-XoxF in the periplasm in the absence of lanthanides; when Ln is present, active Ln-bound XoxF no longer signals through the same route In the model, no-Ln conditions activate mxa and repress xox1 via MxcQE/MxbDM; Ln presence causes mxa repression and xox1 activation Model is explicitly presented as a hypothesis/postulate, not a direct mechanistic demonstration for MxcQ Vu et al. (2016); Pastawan et al. (2020) https://doi.org/10.1128/JB.00937-15 ; https://doi.org/10.7831/ras.8.0_186 (vu2016lanthanidedependentregulationof pages 31-40, pastawan2020biologicalfunctionof pages 6-8)
Lanthanide sensitivity of the regulatory system M. extorquens AM1 Reporter assays for mxa and xox1 promoters demonstrate active response to lanthanides in the same network in which MxcQE functions Supports that MxcQ participates in a highly lanthanide-sensitive regulatory system, even though the exact sensory ligand for MxcQ is unproven La, Ce, Pr, Nd are effective signals in vivo at the system level Differential transcription from mxa and xox1 promoters Maximum growth rate and yield at ≥1 μM La; growth detectable at 2.5 nM La; intermediate expression from both mxa and xox1 at 50–100 nM La Vu et al. (2016) https://doi.org/10.1128/JB.00937-15 (vu2016lanthanidedependentregulationof pages 1-6, vu2016lanthanidedependentregulationof pages 9-14)
Methanol oxidation phenotypes relevant to MxcQ-controlled network M. extorquens AM1 MxcQ is not assayed directly here, but the phenotypes define the physiological output of the regulatory network that controls methanol dehydrogenases The organism preferentially deploys Ln-dependent methanol oxidation when lanthanides are available Methanol plus Ca and/or Ln Growth on methanol via MxaFI, XoxF, and at least one additional Ln-dependent oxidation route With 20 μM La: wild type TD = 5.5 ± 0.2 h; xoxF1 mutant TD = 8.6 ± 0.9 h; xoxF1 xoxF2 TD = 19.1 ± 0.8 h; triple MeDH mutant retained residual activity 9 ± 1 nmol·min⁻¹·mg⁻¹ Vu et al. (2016) https://doi.org/10.1128/JB.00937-15 (vu2016lanthanidedependentregulationof pages 9-14)
AM1 MxcQ used in heterologous biosensor engineering Recombinant E. coli using AM1 MxcQ sensor domain MxcQ sensor region from AM1 was fused to the EnvZ transmitter domain to create MxcQZ AM1; authors describe the imported region as a methanol-sensing domain Suggests MxcQ contains a transferable sensory module responsive to methanol-related input, but this is an engineering inference rather than native mechanistic proof Exogenous methanol in engineered E. coli Activation of OmpR/ompC and GFP reporter in the chimera Max fluorescence reported at 0.01% methanol for MxcQZ AM1; chimeric junction placed near EnvZ residue 254 in their model Selvamani et al. (2020) https://doi.org/10.4014/mbl.1908.08009 (selvamani2020engineeringofrecombinant pages 1-3, selvamani2020engineeringofrecombinant pages 3-5)
Related evidence from other methylotrophs Methylobacterium aquaticum strain 22A; Methylobacillus flagellatus mxcQE is necessary for MxaF-dependent methanol growth in strain 22A; in M. flagellatus, proteins homologous to MxcQ/MxcE were identified, with only the histidine kinase domains matching for the MxcQ-like protein Supports a conserved methylotrophy-regulatory role for MxcQ/MxcE-like systems across methylotrophs Lanthanides and methanol metabolism Control of methanol dehydrogenase expression / Ln response In 22A, PmxcQ expression was constant in wild type but became La-dependently decreasing in ΔlanM; in M. flagellatus, the MxcQ-homologous histidine kinase showed partial homology limited to HK domains Fujitani et al. (2022); Hemmann et al. (2023) https://doi.org/10.3389/fmicb.2022.921636 ; https://doi.org/10.1016/j.jbc.2023.102940 (fujitani2022aperiplasmiclanthanide pages 11-12, jethro2023lanpepsyisa pages 2-3)
Why UniProt may annotate C5ASP2 as NreB-like Annotation / domain-comparison issue UniProt labels C5ASP2 as oxygen sensor histidine kinase NreB / nitrogen regulation protein B, while InterPro domains indicate a generic histidine kinase architecture (including HAMP/HATPase-related modules) consistent with broad HK family membership The available AM1 literature more strongly supports MxcQ as a methanol/lanthanide regulatory sensor kinase than a proven NreB-type oxygen sensor; thus the NreB label is best treated as homology-based annotation, not organism-specific experimental proof Likely based on sequence/domain similarity to histidine kinases rather than direct AM1 characterization None directly shown for nitrate respiration in AM1 target literature No cited AM1 paper demonstrates Fe–S-based oxygen sensing, nitrate-respiration control, or NreABC-like biochemistry for C5ASP2 Comparison across cited AM1 and NreB literature UniProt accession provided by user; comparison supported by cited literature below (vu2016lanthanidedependentregulationof pages 6-9, vu2016lanthanidedependentregulationof pages 31-40, nilkens2013thenreabcsystem pages 80-84, hsueh2013feocfromklebsiella pages 9-9, price2021bacterialapproachesto pages 6-8)
Canonical NreB for comparison Staphylococcus carnosus / staphylococcal NreABC system NreB is a cytosolic HisKA_3-type histidine kinase paired with response regulator NreC and nitrate sensor NreA Established oxygen/redox sensor controlling anaerobic nitrate respiration genes O2 via an O2-labile [4Fe-4S] cluster in/associated with a PAS-like sensor region; nitrate via NreA, which inhibits NreB when nitrate is absent Controls narGHJI, nirRBD, sirAB, narT and other genes for nitrate/nitrite reduction and fermentation Under anaerobic conditions NreB is activated by a [4Fe-4S]²⁺ cluster; autophosphorylates at H159 and transfers phosphate to NreC D53; NreA binding inhibits kinase activity without nitrate Nilkens (2013); Price et al. (2021); Hsueh et al. citing Kamps/Müllner; Barth et al. (2018) https://doi.org/10.1111/mmi.14795 ; https://doi.org/10.1128/jb.00687-13 ; https://doi.org/10.1111/1462-2920.14411 (nilkens2013thenreabcsystem pages 80-84, nilkens2013thenreabcsystem pages 6-9, hsueh2013feocfromklebsiella pages 9-9, barth2018originandphylogenetic pages 1-2, price2021bacterialapproachesto pages 6-8)
NreB mechanism vs. AM1 MxcQ Cross-system comparison NreB has direct biochemical evidence for Fe–S-dependent oxygen sensing and nitrate-respiration regulation; AM1 MxcQ has genetic/physiological evidence for methanol dehydrogenase regulation in the Ln switch Distinguishes a validated NreB oxygen sensor from an MxcQ-like methylotrophy regulator NreB: O2 and nitrate; MxcQ: lanthanides, methanol-state, possibly apo-XoxF NreB: respiratory nitrate genes; MxcQ: mxa/xox1 methanol oxidation programs This contrast is the key reason to treat the UniProt NreB name for C5ASP2 cautiously pending direct biochemical validation in AM1 Comparative synthesis of all above URLs above (vu2016lanthanidedependentregulationof pages 31-40, pastawan2020biologicalfunctionof pages 6-8, nilkens2013thenreabcsystem pages 80-84, nilkens2013thenreabcsystem pages 6-9, price2021bacterialapproachesto pages 6-8)

Table: This table compiles the strongest literature-based evidence for the identity and function of MxcQ/C5ASP2 in Methylorubrum extorquens AM1 and contrasts it with canonical NreB oxygen sensors. It is useful for separating experimentally supported methylotrophy-related roles from broader homology-based histidine kinase annotations.

Recommended AM1-specific functional annotation (evidence-based):
- Gene: mxcQ
- Protein: MxcQ, sensor histidine kinase of the MxcQE two-component system.
- Primary role: Regulation of methanol oxidation gene expression as part of the lanthanide switch; required (with MxcE and other regulators) for expression of the mxa methanol dehydrogenase system and involved in the regulatory state that coordinates mxa versus xox expression depending on lanthanide availability. (vu2016lanthanidedependentregulationof pages 6-9, vu2016lanthanidedependentregulationof pages 31-40, pastawan2020biologicalfunctionof pages 6-8)
- Signal/sensing: Not directly established for AM1 MxcQ; a prominent model proposes apo-XoxF-mediated signaling to MxcQ/MxbD under Ln limitation. (vu2016lanthanidedependentregulationof pages 31-40, pastawan2020biologicalfunctionof pages 6-8)
- Localization: Likely membrane-associated HK with a periplasmic sensor region and cytosolic kinase/transmitter region, supported indirectly by domain-swapping biosensor construction. (selvamani2020engineeringofrecombinant pages 1-3)

Caveat: Although UniProt labels C5ASP2 as an NreB-like oxygen sensor, the AM1 literature retrieved here supports methylotrophy/Ln-switch regulation and does not provide AM1-specific biochemical evidence for Fe–S oxygen sensing or NreABC-like nitrate respiration regulation by MxcQ. (vu2016lanthanidedependentregulationof pages 31-40, nilkens2013thenreabcsystem pages 80-84)

References

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  8. (vu2016lanthanidedependentregulationof pages 1-6): Huong N. Vu, Gabriel A. Subuyuj, Srividhya Vijayakumar, Nathan M. Good, N. Cecilia Martinez-Gomez, and Elizabeth Skovran. Lanthanide-dependent regulation of methanol oxidation systems in methylobacterium extorquens am1 and their contribution to methanol growth. Journal of Bacteriology, 198:1250-1259, Apr 2016. URL: https://doi.org/10.1128/jb.00937-15, doi:10.1128/jb.00937-15. This article has 227 citations and is from a peer-reviewed journal.

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Artifacts

Citations

  1. selvamani2020engineeringofrecombinant pages 1-3
  2. vu2016lanthanidedependentregulationof pages 1-6
  3. vu2016lanthanidedependentregulationof pages 6-9
  4. pastawan2020biologicalfunctionof pages 6-8
  5. jethro2023lanpepsyisa pages 1-2
  6. vu2016lanthanidedependentregulationof pages 9-14
  7. nilkens2013thenreabcsystem pages 80-84
  8. vu2016lanthanidedependentregulationof pages 31-40
  9. nilkens2013thenreabcsystem pages 6-9
  10. hsueh2013feocfromklebsiella pages 9-9
  11. selvamani2020engineeringofrecombinant pages 3-5
  12. jethro2023lanpepsyisa pages 2-3
  13. fujitani2022aperiplasmiclanthanide pages 11-12
  14. price2021bacterialapproachesto pages 6-8
  15. barth2018originandphylogenetic pages 1-2
  16. 4Fe–4S
  17. 4Fe-4S
  18. 4fe-4s
  19. 4fe–4s
  20. https://doi.org/10.1128/JB.00937-15
  21. https://doi.org/10.7831/ras.8.0_186
  22. https://doi.org/10.4014/mbl.1908.08009
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  24. https://doi.org/10.1016/j.jbc.2023.102940
  25. https://doi.org/10.1111/mmi.14795
  26. https://doi.org/10.1128/jb.00687-13
  27. https://doi.org/10.1111/1462-2920.14411
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  31. https://doi.org/10.4014/mbl.1908.08009,
  32. https://doi.org/10.1016/j.jbc.2023.102940,
  33. https://doi.org/10.3389/fmicb.2022.921636,
  34. https://doi.org/10.1111/mmi.14795,
  35. https://doi.org/10.1111/1462-2920.14411,