Protein: Large ribosomal subunit assembly factor BipA (EC 3.6.5.-) (50S ribosomal subunit assembly factor BipA) (GTP-binding protein BipA/TypA) (Ribosome assembly factor BipA) (Ribosome-dependent GTPase BipA) (Tyrosine phosphorylated protein A) (P0DTT0)
Organism: Escherichia coli (strain K12)
Function: A 50S ribosomal subunit assembly protein with GTPase and nucleotide-independent chaperone activity, required for 50S subunit assembly at low temperatures, may also play a role in translation. Genetic and deletion evidence suggests this is involved in ribosome assembly at low temperatures; it may also affect translation (Probable). Involved in incorporation of ribosomal protein L6 into precursor 44S ribosomal particles at low temperatures. Also has chaperone activity which does not require nucleotides. Binds GDP, ppGpp and GDPCP (a nonhydrolyzable GTP analog) with similar affinity; the conformation of the protein does not significantly change upon nucleotide binding. Interacts with ribosomes. Binds the 70S ribosome between the 30S and 50S subunits, in a similar position as ribosome-bound EF-G; it contacts a number of ribosomal proteins, both rRNAs and the A-site tRNA. Ribosome binding alters its conformation. Genetically its function does not overlap LepA, and it acts in a different pathway during ribosome assembly than does RNA helicase DeaD. GTPase that affects interactions between enteropathogenic E.coli (EPEC) and epithelial cells. Probably regulates expression of proteins required for (at least) K5 polysaccharide production (Probable). Deletion mutants of bipA are suppressed by an rluC deletion, which no longer modifies uracils 955, 2504 and 2580 to pseudouridine in 23S rRNA; there are 5 other pseudouridine synthases in E.coli, only rluC suppresses this phenotype. Mutating 23S rRNA so the 3 uracils are other nucleotides also suppresses the bipA deletion; pseudouridine-2504 is required for ribosome assembly and translational accuracy.
Subcellular location: Cytoplasm {ECO:0000255|HAMAP-Rule:MF_00849, ECO:0000269|PubMed:30305394, ECO:0000269|Ref.12}. Note=Associates with 70S ribosomes and 30S and 50S subunits in the presence of GMPPNP (a nonhydrolyzable GTP analog) at both 20 and 37 degrees Celsius; no change in ribosome association is seen in the presence of ppGpp or when the stringent response is triggered. {ECO:0000269|PubMed:30305394}.
Interaction partners:
- GTPase Der
- DNA-binding protein Fis
- Large ribosomal subunit protein uL1
- GTPase ObgE/CgtA
- Elongation factor Ts
- Ribosome-binding ATPase YchF
- Trigger factor
- GMP synthase
Sequence:
MIEKLRNIAIIAHVDHGKTTLVDKLLQQSGTFDSRAETQERVMDSNDLEKERGITILAKNTAIKWNDYRINIVDTPGHADFGGEVERVMSMVDSVLLVVDAFDGPMPQTRFVTKKAFAYGLKPIVVINKVDRPGARPDWVVDQVFDLFVNLDATDEQLDFPIVYASALNGIAGLDHEDMAEDMTPLYQAIVDHVPAPDVDLDGPFQMQISQLDYNSYVGVIGIGRIKRGKVKPNQQVTIIDSEGKTRNAKVGKVLGHLGLERIETDLAEAGDIVAITGLGELNISDTVCDTQNVEALPALSVDEPTVSMFFCVNTSPFCGKEGKFVTSRQILDRLNKELVHNVALRVEETEDADAFRVSGRGELHLSVLIENMRREGFELAVSRPKVIFREIDGRKQEPYENVTLDVEEQHQGSVMQALGERKGDLKNMNPDGKGRVRLDYVIPSRGLIGFRSEFMTMTSGTGLLYSTFSHYDDVRPGEVGQRQNGVLISNGQGKAVAFALFGLQDRGKLFLGHGAEVYEGQIIGIHSRSNDLTVNCLTGKKLTNMRASGTDEAVVLVPPIRMTLEQALEFIDDDELVEVTPTSIRIRKRHLTENDRRRANRAPKDD