3IIR

Crystal Structure of Miraculin like protein from seeds of Murraya koenigii

Summary for 3IIR

• Entry DOI: 10.2210/pdb3iir/pdb
• Descriptor: Trypsin inhibitor (2 entities in total)
• Functional Keywords: beta-trefoil fold, kunitz trypsin inhibitor, hydrolase inhibitor
• Biological source: Murraya koenigii
• Total number of polymer chains: 2
• Total formula weight: 41518.58

Authors

Gahloth, D.,Selvakumar, P.,Shee, C.,Kumar, P.,Sharma, A.K. (deposition date: 2009-08-03, release date: 2009-12-08, Last modification date: 2024-10-30)

Primary citation

Gahloth, D.,Selvakumar, P.,Shee, C.,Kumar, P.,Sharma, A.K.
Cloning, sequence analysis and crystal structure determination of a miraculin-like protein from Murraya koenigii
Arch.Biochem.Biophys., 494:15-22, 2010

PubMed Abstract: Earlier, the purification of a 21.4kDa protein with trypsin inhibitory activity from seeds of Murraya koenigii has been reported. The present study, based on the amino acid sequence deduced from both cDNA and genomic DNA, establishes it to be a miraculin-like protein and provides crystal structure at 2.9A resolution. The mature protein consists of 190 amino acid residues with seven cysteines arranged in three disulfide bridges. The amino acid sequence showed maximum homology and formed a distinct cluster with miraculin-like proteins, a soybean Kunitz super family member, in phylogenetic analyses. The major differences in sequence were observed at primary and secondary specificity sites in the reactive loop when compared to classical Kunitz family members. The crystal structure analysis showed that the protein is made of twelve antiparallel beta-strands, loops connecting beta-strands and two short helices. Despite similar overall fold, it showed significant differences from classical Kunitz trypsin inhibitors.

PubMed: 19914199
DOI: 10.1016/j.abb.2009.11.008

Experimental method

X-RAY DIFFRACTION (2.9 Å)