Selectivity of metal binding and metal-induced stability of Escherichia coli NikR.


Abstract

NikR from Escherichia coli is a nickel-responsive transcription factor that regulates the expression of a nickel ion transporter. Metal analysis reveals that NikR can bind a variety of divalent transition metals, including Ni(II), Cu(II), Zn(II), Co(II), and Cd(II). The selectivity of metal binding to NikR was investigated by using electronic absorption spectroscopy and small-molecule competitors. The relative affinities, Mn(II) < Co(II) < Ni(II) < Cu(II) > or = Zn(II), follow the Irving-Williams series of metal-complex stabilities. Similar metal affinities were measured for the isolated metal-binding domain of NikR. To determine if any of these metal ions confer a differential effect on NikR, the stability of the metal-bound complexes was examined. In both thermal and chemical denaturation experiments, nickel binding stabilizes the protein more than any of the other metals tested. Thermal denaturation experiments indicate that metal dissociation occurs after loss of secondary structure, but there was no evidence for metal binding to unfolded protein following reversible chemical denaturation. These experiments demonstrate that, although several different metals can bind to NikR, nickel exerts a selective allosteric effect. The implications of these experiments on the in vivo role of NikR as a nickel metalloregulator are discussed. Study holds ProTherm entries: 17140, 17141, 17142, 17143, 17144, 17145, 17146, 17147, 17148, 17149, 17150, 17151, 17152, 17153, 17154, 17155, 17156, 17157, 17158, 17159, 17160, 17161, 17162, 17163, 17164, 17165, 17166 Extra Details: apo form. Transition 1. nickel-responsive transcription factor; transition metals; metal-binding domain; nickel metalloregulator

Submission Details

ID: T72dyAPA4

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:49 p.m.

Version: 1

Publication Details
Wang SC;Dias AV;Bloom SL;Zamble DB,Biochemistry (2004) Selectivity of metal binding and metal-induced stability of Escherichia coli NikR. PMID:15287729
Additional Information

Structure view and single mutant data analysis

Study data

No weblogo for data of varying length.
Colors: D E R H K S T N Q A V I L M F Y W C G P
 

Data Distribution

Studies with similar sequences (approximate matches)

Correlation with other assays (exact sequence matches)


Relevant PDB Entries

Structure ID Release Date Resolution Structure Title
1Q5Y 2003-09-30 1.4 Nickel-Bound C-terminal Regulatory Domain of NikR
3BKT 2008-02-19 1.5 Copper-bound C-terminal Domain of NikR
3BKF 2008-02-19 1.9 Zinc-bound C-terminal Domain of NikR
3BKU 2008-02-19 2.1 Apo C-terminal Domain of NikR
2HZA 2006-08-22 2.1 Nickel-bound full-length Escherichia coli NikR
1Q5V 2003-09-30 2.3 Apo-NikR
3OD2 2010-09-08 2.6 E. coli NikR soaked with excess nickel ions
2HZV 2006-08-22 3.1 NikR-operator DNA complex

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
91.0 Nickel-responsive regulator A4W9Y8 NIKR_ENT38
97.6 Nickel-responsive regulator A9MM66 NIKR_SALAR
97.6 Nickel-responsive regulator B7LSV6 NIKR_ESCF3
98.8 Nickel-responsive regulator A8AR62 NIKR_CITK8
100.0 Nickel-responsive regulator B5BHM4 NIKR_SALPK
100.0 Nickel-responsive regulator Q5PJN1 NIKR_SALPA
100.0 Nickel-responsive regulator P64413 NIKR_SALTY
100.0 Nickel-responsive regulator P64414 NIKR_SALTI
100.0 Nickel-responsive regulator B4TYY1 NIKR_SALSV
100.0 Nickel-responsive regulator B5RGU2 NIKR_SALG2
100.0 Nickel-responsive regulator B5R3Y5 NIKR_SALEP
100.0 Nickel-responsive regulator Q57IP3 NIKR_SALCH
99.2 Nickel-responsive regulator B7UL33 NIKR_ECO27
99.2 Nickel-responsive regulator B6I346 NIKR_ECOSE
99.2 Nickel-responsive regulator Q0TBX7 NIKR_ECOL5
100.0 Nickel-responsive regulator B1LIE4 NIKR_ECOSM
100.0 Nickel-responsive regulator Q3YW47 NIKR_SHISS
100.0 Nickel-responsive regulator P0A6Z9 NIKR_SHIFL
100.0 Nickel-responsive regulator Q0SZJ2 NIKR_SHIF8
100.0 Nickel-responsive regulator Q32AQ0 NIKR_SHIDS
100.0 Nickel-responsive regulator Q31VE5 NIKR_SHIBS
100.0 Nickel-responsive regulator B2U4B0 NIKR_SHIB3
100.0 Nickel-responsive regulator Q1R5D7 NIKR_ECOUT
100.0 Nickel-responsive regulator B7NEA8 NIKR_ECOLU
100.0 Nickel-responsive regulator P0A6Z6 NIKR_ECOLI
100.0 Nickel-responsive regulator B1J0E9 NIKR_ECOLC
100.0 Nickel-responsive regulator P0A6Z7 NIKR_ECOL6
100.0 Nickel-responsive regulator A1AH17 NIKR_ECOK1
100.0 Nickel-responsive regulator A8A5T9 NIKR_ECOHS
100.0 Nickel-responsive regulator B1X7T9 NIKR_ECODH
100.0 Nickel-responsive regulator C4ZW30 NIKR_ECOBW
100.0 Nickel-responsive regulator B7M2P4 NIKR_ECO8A
100.0 Nickel-responsive regulator B7N1R9 NIKR_ECO81
100.0 Nickel-responsive regulator B7NN95 NIKR_ECO7I
100.0 Nickel-responsive regulator B5YUQ6 NIKR_ECO5E
100.0 Nickel-responsive regulator P0A6Z8 NIKR_ECO57
100.0 Nickel-responsive regulator B7L5T4 NIKR_ECO55
100.0 Nickel-responsive regulator B7MDX1 NIKR_ECO45
100.0 Nickel-responsive regulator A7ZT19 NIKR_ECO24