sopB

Existing Annotations Review

GO Term	Evidence	Action	Reason
GO:0003677 DNA binding	IEA GO_REF:0000002	MODIFY	Summary: SopB binds DNA; its defining activity is sequence-specific binding to the sopC centromere. Reason: True but less specific than the evidence. Purified SopB binds the sopC repeats specifically, and crystal structures show SopB bound to its site. It also coats non-specific DNA, but recognition of sopC is the activity that defines it. Sequence-specific DNA binding (GO:0043565) is a descendant of DNA binding and is the term used for chromosomal ParB. Proposed replacements: sequence-specific DNA binding Supporting Evidence: PMID:2670941 SopB protein binds to the sopC region, in which 12 direct repeats of 43-base pairs nucleotides exist. PMID:20236989 it binds sopC to form a partition complex, which recruits SopA
GO:0043565 sequence-specific DNA binding	IDA PMID:2670941 Purification and characterization of SopA and SopB proteins ...	NEW	Summary: SopB binds the sopC centromere repeats. Reason: The replacement for the electronic DNA binding row, recorded with its experimental source (gel retardation and footprinting of purified SopB, and SopB-DNA crystal structures). Supporting Evidence: PMID:2670941 SopB protein binds to the sopC region, in which 12 direct repeats of 43-base pairs nucleotides exist. PMID:20236989 it binds sopC to form a partition complex, which recruits SopA
GO:0043273 CTPase activity	IDA PMID:34286695 CTP and parS coordinate ParB partition complex dynamics and ...	NEW	Summary: Purified SopB (ParB of F) hydrolyses CTP, stimulated by sopC DNA. Reason: Direct measurement on the F plasmid protein, called ParBF in the paper (the F system is SopA/B/C). Hydrolysis is specific for CTP and follows Michaelis-Menten kinetics, with the maximum rate raised about threefold by sopC DNA. CTP promotes loading of multiple SopB molecules onto sopC-containing DNA, the clamp behaviour shared with chromosomal ParB. Supporting Evidence: PMID:34286695 using F-plasmid ParAFBFSF (also called SopA/B/C) as a model system PMID:34286695 ParBF had negligible activity for all NTPs other than CTP
GO:0001671 ATPase activator activity	IDA PMID:19740757 Dual role of DNA in regulating ATP hydrolysis by the SopA pa...	NEW	Summary: SopB stimulates SopA ATP hydrolysis through an arginine finger. Reason: SopB does not bind ATP itself but stimulates the ATPase of its partner: purified SopB raises SopA ATP hydrolysis above the DNA-stimulated level, and it provides the catalytic arginine finger. This is the coupling between the two partition roles, and the activity that drives separation of the partition complexes. Supporting Evidence: PMID:1406581 The ATPase activity in the presence of DNA was further stimulated by addition of the SopB protein. PMID:19740757 which we show here to provide an arginine-finger motif
GO:0030541 plasmid partitioning	IMP PMID:10395819 The F plasmid centromere, sopC, is required for full repress...	NEW	Summary: SopB is required for F plasmid partition. Reason: SopB does work in the process: it forms the partition complex at sopC and activates SopA. sopB missense mutants were isolated by screening for unstable inheritance of mini-F. Supporting Evidence: PMID:10395819 We have isolated sop mutants by screening for unstable inheritance of mutagenized mini-F DNA. PMID:10395819 Four of the mutants resulted from different missense mutations in sopB.
GO:0045892 negative regulation of DNA-templated transcription	IMP PMID:9529520 Autoregulation of the partition genes of the mini-F plasmid ...	NEW	Summary: SopB, with SopA, represses the sopAB operon. Reason: Repression needs SopA and SopB together; SopB alone does not bind the operator but enhances SopA binding there, and sopC strengthens the repression. Non-core: it keeps Sop protein levels in the range that partition needs. Supporting Evidence: PMID:9529520 the sopAB operon is repressed by the cooperative action of SopA and SopB PMID:10395819 it interacts with SopA to repress transcription of the sopAB operon
GO:0002135 CTP binding	IC PMID:34286695 CTP and parS coordinate ParB partition complex dynamics and ...	NEW	Summary: SopB binds the CTP it hydrolyses, and CTP promotes its loading on sopC. Reason: Curator inference from the measured, CTP-specific hydrolysis by purified SopB (ParBF), which requires CTP binding. Recorded separately because GO does not derive CTP binding from CTPase activity. Supporting Evidence: PMID:34286695 ParBF had negligible activity for all NTPs other than CTP