1RKU

Crystal Structure of ThrH gene product of Pseudomonas Aeruginosa

Summary for 1RKU

• Entry DOI: 10.2210/pdb1rku/pdb
• Related: 1RKV
• Descriptor: homoserine kinase, MAGNESIUM ION, 1,2-ETHANEDIOL, ... (4 entities in total)
• Functional Keywords: phosphoserine phosphatase, phosphoserine:homoserine phosphotransferase, thrh, phosphoserine phosphoryl donor, transferase
• Biological source: Pseudomonas aeruginosa
• Total number of polymer chains: 2
• Total formula weight: 47886.04

Authors

Singh, S.K.,Yang, K.,Subramanian, K.,Karthikeyan, S.,Huynh, T.,Zhang, X.,Phillips, M.A.,Zhang, H. (deposition date: 2003-11-23, release date: 2004-03-30, Last modification date: 2024-02-14)

Primary citation

Singh, S.K.,Yang, K.,Karthikeyan, S.,Huynh, T.,Zhang, X.,Phillips, M.A.,Zhang, H.
The thrH Gene Product of Pseudomonas aeruginosa Is a Dual Activity Enzyme with a Novel Phosphoserine:Homoserine Phosphotransferase Activity.
J.Biol.Chem., 279:13166-13173, 2004

PubMed Abstract: The thrH gene product of Pseudomonas aeruginosa has been shown to complement both homoserine kinase (thrB gene product) and phosphoserine phosphatase (serB gene product) activities in vivo. Sequence comparison has revealed that ThrH is related to phosphoserine phosphatases (PSP, EC 3.1.3.3) and belongs to the l-2-haloacid dehalogenase-like protein superfamily. We have solved the crystal structures of ThrH in the apoform and in complex with a bound product phosphate. The structure confirms an overall fold similar to that of PSP. Most of the catalytic residues of PSP are also conserved in ThrH, suggesting that similar catalytic mechanisms are used by both enzymes. Spectrophotometry-based in vitro assays show that ThrH is indeed a phosphoserine phosphatase with a K(m) of 0.207 mm and k(cat) of 13.4 min(-1), comparable with those of other PSPs. More interestingly, using high pressure liquid chromatography-based assays, we have demonstrated that ThrH is able to further transfer the phosphoryl group to homoserine using phosphoserine as the phosphoryl group donor, indicating that ThrH has a novel phosphoserine:homoserine phosphotransferase activity.

PubMed: 14699121
DOI: 10.1074/jbc.M311393200

Experimental method

X-RAY DIFFRACTION (1.47 Å)