Molecular Insights on the Assembling of ParB1 and ParB1- parS1 Partition Complex

Anu A, Lata S, Chaudhuri B
ACS Bio & Med Chem Au (2026 Jun 19)

doi: 10.1021/acsbiomedchemau.5c00284

Submitted to SASBDB: 2024 Jun 28 Published in SASBDB: 2026 Jun 25

SASDVD3 – Full-length dimeric Probable chromosome-partitioning protein ParB-peak Sample: Probable chromosome-partitioning protein ParB dimer, 68 kDa Vibrio cholerae serotype … protein Buffer: 20 mM Tris,100 mM NaCl,2% glycerol,1 mM EDTA,2 mM DTT,5 mM MgCl2, pH: 7.5 Experiment: SAXS data collected at BM29, ESRF on 2020 Nov 2 RgGuinier 4.2 nm Dmax 16.7 nm VolumePorod 130 nm3

SASDVE3 – Probable chromosome-partitioning protein ParB in the presence of cytidine triphosphate (vcParB1-CTP-peak) Sample: Probable chromosome-partitioning protein ParB dimer, 68 kDa Vibrio cholerae serotype … protein Buffer: 20 mM Tris pH 7.5, 100 mM NaCl, 2% glycerol, 1 mM EDTA, 2 mM DTT, 5 mM MgCl2, 1.2 mM CTP, pH: Experiment: SAXS data collected at BM29, ESRF on 2020 Nov 2 RgGuinier 3.9 nm Dmax 16.0 nm VolumePorod 124 nm3

SASDVF3 – Probable chromosome-partitioning protein ParB (vcParB1) at 13 mg/ml Sample: Probable chromosome-partitioning protein ParB dimer, 68 kDa Vibrio cholerae serotype … protein Buffer: 20 mM Tris pH 7.5, 100 mM NaCl, 5% glycerol, 1 mM EDTA, 5 mM BME, 5 mM MgCl2, pH: Experiment: SAXS data collected at BM29, ESRF on 2023 Jul 1 RgGuinier 4.7 nm Dmax 21.6 nm VolumePorod 189 nm3

SASDVG3 – Probable chromosome-partitioning protein ParB (vcParB1) at 12 mg/ml Sample: Probable chromosome-partitioning protein ParB dimer, 68 kDa Vibrio cholerae serotype … protein Buffer: 20 mM Tris pH 7.5, 100 mM NaCl, 5% glycerol, 1 mM EDTA, 5 mM BME, 5 mM MgCl2, pH: Experiment: SAXS data collected at BM29, ESRF on 2023 Jul 1 RgGuinier 4.7 nm Dmax 21.6 nm VolumePorod 186 nm3

SASDVH3 – Probable chromosome-partitioning protein ParB (vcParB1) at 10 mg/ml Sample: Probable chromosome-partitioning protein ParB dimer, 68 kDa Vibrio cholerae serotype … protein Buffer: 20 mM Tris pH 7.5, 100 mM NaCl, 5% glycerol, 1 mM EDTA, 5 mM BME, 5 mM MgCl2, pH: Experiment: SAXS data collected at BM29, ESRF on 2023 Jul 1 RgGuinier 4.5 nm Dmax 19.9 nm VolumePorod 164 nm3

SASDVJ3 – Probable chromosome-partitioning protein ParB (vcParB1) at 8 mg/ml Sample: Probable chromosome-partitioning protein ParB dimer, 68 kDa Vibrio cholerae serotype … protein Buffer: 20 mM Tris pH 7.5, 100 mM NaCl, 5% glycerol, 1 mM EDTA, 5 mM BME, 5 mM MgCl2, pH: Experiment: SAXS data collected at BM29, ESRF on 2023 Jul 1 RgGuinier 4.4 nm Dmax 19.2 nm VolumePorod 155 nm3

SASDVK3 – Probable chromosome-partitioning protein ParB bound to parS1 DNA (vcParB1-parS1-peak) Sample: Probable chromosome-partitioning protein ParB dimer, 68 kDa Vibrio cholerae serotype … protein ParS1 dimer, 10 kDa Vibrio cholerae DNA Buffer: 20 mM Tris pH 7.5,100 mM NaCl, 2% glycerol, 1 mM EDTA, 2 mM DTT, 5 mM MgCl2, pH: Experiment: SAXS data collected at BM29, ESRF on 2020 Nov 2 RgGuinier 3.8 nm Dmax 14.7 nm VolumePorod 127 nm3

SASDVL3 – Probable chromosome-partitioning protein ParB linker triple mutant (vcParB1-linker) at 12 mg/ml Sample: Probable chromosome-partitioning protein ParB (P235G, D237G, K239A) dimer, 68 kDa Vibrio cholerae serotype … protein Buffer: 20 mM Tris pH 7.5, 100 mM NaCl, 5% glycerol, 1 mM EDTA, 5 mM BME, 5 mM MgCl2, pH: Experiment: SAXS data collected at BM29, ESRF on 2023 Jul 1 RgGuinier 5.6 nm Dmax 26.9 nm VolumePorod 240 nm3

SASDVM3 – Probable chromosome-partitioning protein ParB linker triple mutant (vcParB1-linker) at 10 mg/ml Sample: Probable chromosome-partitioning protein ParB (P235G, D237G, K239A) dimer, 68 kDa Vibrio cholerae serotype … protein Buffer: 20 mM Tris pH 7.5, 100 mM NaCl, 5% glycerol, 1 mM EDTA, 5 mM BME, 5 mM MgCl2, pH: Experiment: SAXS data collected at BM29, ESRF on 2023 Jul 1 RgGuinier 5.4 nm Dmax 24.8 nm VolumePorod 224 nm3

SASDVN3 – Probable chromosome-partitioning protein ParB linker triple mutant (vcParB1-linker) at 8 mg/ml Sample: Probable chromosome-partitioning protein ParB (P235G, D237G, K239A) dimer, 68 kDa Vibrio cholerae serotype … protein Buffer: 20 mM Tris pH 7.5, 100 mM NaCl, 5% glycerol, 1 mM EDTA, 5 mM BME, 5 mM MgCl2, pH: Experiment: SAXS data collected at BM29, ESRF on 2023 Jul 1 RgGuinier 5.1 nm Dmax 24.6 nm VolumePorod 240 nm3

SASDVP3 – Probable chromosome-partitioning protein ParB linker triple mutant (vcParB1-linker) at 6 mg/ml Sample: Probable chromosome-partitioning protein ParB (P235G, D237G, K239A) dimer, 68 kDa Vibrio cholerae serotype … protein Buffer: 20 mM Tris pH 7.5, 100 mM NaCl, 5% glycerol, 1 mM EDTA, 5 mM BME, 5 mM MgCl2, pH: Experiment: SAXS data collected at BM29, ESRF on 2023 Jul 1 RgGuinier 4.8 nm Dmax 22.0 nm VolumePorod 206 nm3

SASDVQ3 – Truncation variant (amino acids 39-231) of Probable chromosome-partitioning protein ParB (vcParB1trunc I) Sample: Probable chromosome-partitioning protein ParB monomer, 24 kDa Vibrio cholerae serotype … protein Buffer: 20 mM Tris pH 7.5, 100 mM NaCl, 5% glycerol, 1mM EDTA, 5 mM BME, 5 mM MgCl2, pH: Experiment: SAXS data collected at BM29, ESRF on 2023 Jul 1 RgGuinier 2.7 nm Dmax 9.9 nm VolumePorod 55 nm3

SASDVR3 – Truncation variant (amino acids 39-231) of Probable chromosome-partitioning protein ParB (vcParB1trunc II) Sample: Probable chromosome-partitioning protein ParB monomer, 24 kDa Vibrio cholerae serotype … protein Buffer: 20 mM Tris pH 7.5, 100 mM NaCl, 5% glycerol, 1 mM EDTA, 5 mM BME, 5 mM MgCl2, pH: Experiment: SAXS data collected at BM29, ESRF on 2023 Jul 1 RgGuinier 2.5 nm Dmax 9.5 nm VolumePorod 51 nm3

SASDVS3 – Truncation variant (amino acids 39-231) of Probable chromosome-partitioning protein ParB (vcParB1trunc III) Sample: Probable chromosome-partitioning protein ParB monomer, 24 kDa Vibrio cholerae serotype … protein Buffer: 20 mM Tris pH7.5, 100 mM NaCl, 5% glycerol, 1 mM EDTA, 5 mM BME, 5 mM MgCl2, pH: Experiment: SAXS data collected at BM29, ESRF on 2023 Jul 1 RgGuinier 2.5 nm Dmax 9.7 nm VolumePorod 44 nm3

SASDVT3 – Truncation variant (amino acids 39-231) of Probable chromosome-partitioning protein ParB (vcParB1trunc IV) Sample: Probable chromosome-partitioning protein ParB monomer, 24 kDa Vibrio cholerae serotype … protein Buffer: 20 mM Tris pH 7.5, 100 mM NaCl, 5% glycerol, 1 mM EDTA, 5 mM BME, 5 mM MgCl2, pH: Experiment: SAXS data collected at BM29, ESRF on 2023 Jul 1 RgGuinier 2.4 nm Dmax 8.5 nm VolumePorod 41 nm3

SASDVU3 – Truncation variant (amino acids 39-231) of Probable chromosome-partitioning protein ParB (vcParB1trunc V) Sample: Probable chromosome-partitioning protein ParB monomer, 24 kDa Vibrio cholerae serotype … protein Buffer: 20 mM Tris pH 7.5, 100 mM NaCl, 5% glycerol, 1 mM EDTA, 5 mM BME, 5 mM MgCl2, pH: Experiment: SAXS data collected at BM29, ESRF on 2023 Jul 1 RgGuinier 2.3 nm Dmax 8.2 nm VolumePorod 38 nm3

SASDVV3 – Truncation variant (amino acids 39-231) of Probable chromosome-partitioning protein ParB (vcParB1trunc VI) Sample: Probable chromosome-partitioning protein ParB monomer, 24 kDa Vibrio cholerae serotype … protein Buffer: 20 mM Tris pH 7.5, 100 mM NaCl, 5% glycerol, 1 mM EDTA, 5 mM BME, 5 mM MgCl2, pH: Experiment: SAXS data collected at BM29, ESRF on 2023 Jul 1 RgGuinier 2.2 nm Dmax 7.4 nm VolumePorod 37 nm3