Structure of PDB 1bxr Chain A

Receptor sequence

>1bxrA (length=1073) Species: 562 (Escherichia coli)

MPKRTDIKSILILGAGPIVIGQACEFDYSGAQACKALREEGYRVILVNSN
PATIMTDPEMADATYIEPIHWEVVRKIIEKERPDAVLPTMGGQTALNCAL
ELERQGVLEEFGVTMIGATADAIDKAEDRRRFDVAMKKIGLETARSGIAH
TMEEALAVAADVGFPCIIRPSFTMGGSGGGIAYNREEFEEICARGLDLSP
TKELLIDESLIGWKEYEMEVVRDKNDNCIIVCSIENFDAMGIHTGDSITV
APAQTLTDKEYQIMRNASMAVLREIGVETGGSNVQFAVNPKNGRLIVIEM
NPRVSRSSALASKATGFPIAKVAAKLAVGYTLDELMNDITGGRTPASFEP
SIDYVVTKIPRFNFEKFAGANDRLTTQMKSVGEVMAIGRTQQESLQKALR
GLEVGATGFDPKVSLDDPEALTKIRRELKDAGADRIWYIADAFRAGLSVD
GVFNLTNIDRWFLVQIEELVRLEEKVAEVGITGLNADFLRQLKRKGFADA
RLAKLAGVREAEIRKLRDQYDLHPVYKRVDTCAAEFATDTAYMYSTYEEE
CEANPSTDREKIMVLGGGPNRIGQGIEFDYCCVHASLALREDGYETIMVN
CNPETVSTDYDTSDRLYFEPVTLEDVLEIVRIEKPKGVIVQYGGQTPLKL
ARALEAAGVPVIGTSPDAIDRAEDRERFQHAVERLKLKQPANATVTAIEM
AVEKAKEIGYPLVVRPSYVLGGRAMEIVYDEADLRRYFQTAVSVSNDAPV
LLDHFLDDAVEVDVDAICDGEMVLIGGIMEHIEQAGVHSGDSACSLPAYT
LSQEIQDVMRQQVQKLAFELQVRGLMNVQFAVKNNEVYLIEVNPRAARTV
PFVSKATGVPLAKVAARVMAGKSLAEQGVTKEVIPPYYSVKEVVLPFNKF
PGVDPLLGPEMRSTGEVMGVGRTFAEAFAKAQLGSNSTMKKHGRALLSVR
EGDKERVVDLAAKLLKQGFELDATHGTAIVLGEAGINPRLVNKVHEGRPH
IQDRIKNGEYTYIINTTSGRRAIEDSRVIRRSALQYKVHYDTTLNGGFAT
AMALNADATEKVISVQEMHAQIK

3D structure

• PDB: 1bxr Carbamoyl phosphate synthetase: closure of the B-domain as a result of nucleotide binding.
• Chain: A
• Resolution: 2.1 Å

Enzymatic activity

• Catalytic site (original residue number in PDB): R129 R169 M174 G176 K202 E215 H243 N283 Q285 E299 N301 R303 S307 D338 G507 K634 R715 G721 G722 S745 E761 D769 Q829 E841 N843 R848 P901
• Catalytic site (residue number reindexed from 1): R129 R169 M174 G176 K202 E215 H243 N283 Q285 E299 N301 R303 S307 D338 G507 K634 R715 G721 G722 S745 E761 D769 Q829 E841 N843 R848 P901
• Enzyme Commision number: 6.3.4.16: carbamoyl-phosphate synthase (ammonia).
  6.3.5.5: carbamoyl-phosphate synthase (glutamine-hydrolyzing).

Interaction with ligand

Site #	Ligand	Ligand chain	Binding residues on receptor (original residue number in PDB)	Binding residues on receptor (residue number reindexed from 1)	Binding affinity
BS01	MN	A	E299 N301	E299 N301
BS02	MN	A	Q829 E841	Q829 E841
BS03	MN	A	E841 N843	E841 N843
BS04	ANP	A	R129 I167 R169 M174 G175 G176 L210 I211 E215 M240 G241 H243 T244 Q285 E299 R306 T376	R129 I167 R169 M174 G175 G176 L210 I211 E215 M240 G241 H243 T244 Q285 E299 R306 T376	PDBbind-CN: -logKd/Ki=3.40,Ki=0.4mM
BS05	ANP	A	R675 V713 R715 L720 G721 G722 M725 D753 F755 L756 E761 A785 G786 V787 H788 Q829 E841 N843 R848	R675 V713 R715 L720 G721 G722 M725 D753 F755 L756 E761 A785 G786 V787 H788 Q829 E841 N843 R848	PDBbind-CN: -logKd/Ki=3.40,Ki=0.4mM
BS06	ORN	A	E783 D791 E892 L907 D1041 T1042	E783 D791 E892 L907 D1041 T1042

Gene Ontology

Molecular Function

• GO:0000166 nucleotide binding
• GO:0004087 carbamoyl-phosphate synthase (ammonia) activity
• GO:0004088 carbamoyl-phosphate synthase (glutamine-hydrolyzing) activity
• GO:0005515 protein binding
• GO:0005524 ATP binding
• GO:0016597 amino acid binding
• GO:0016874 ligase activity
• GO:0046872 metal ion binding

Biological Process

• GO:0006221 pyrimidine nucleotide biosynthetic process
• GO:0006526 L-arginine biosynthetic process
• GO:0006541 glutamine metabolic process
• GO:0008652 amino acid biosynthetic process
• GO:0019856 pyrimidine nucleobase biosynthetic process
• GO:0044205 'de novo' UMP biosynthetic process

Cellular Component

• GO:0005737 cytoplasm
• GO:0005829 cytosol
• GO:0005951 carbamoyl-phosphate synthase complex

External links

• PDB: RCSB:1bxr, PDBe:1bxr, PDBj:1bxr
• PDBsum: 1bxr
• PubMed: 10029528
• UniProt: P00968|CARB_ECOLI Carbamoyl phosphate synthase large chain (Gene Name=carB)