3PBC

Peptidase module of the peptidoglycan hydrolase RipA (Rv1477) from Mycobacterium tuberculosis at 1.38 resolution

3PBC の概要

• エントリーDOI: 10.2210/pdb3pbc/pdb
• 関連するPDBエントリー: 3PBI 3S0Q
• 分子名称: INVASION PROTEIN (2 entities in total)
• 機能のキーワード: petidoglycan, cell wall, extracellular, peptidoglycan hydrolase, nlpc -like module, hydrolase
• 由来する生物種: Mycobacterium tuberculosis
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 22607.65

構造登録者

Schnell, R.,Both, D.,Schneider, G. (登録日: 2010-10-20, 公開日: 2011-08-31, 最終更新日: 2024-02-21)

主引用文献

Both, D.,Schneider, G.,Schnell, R.
Peptidoglycan Remodeling in Mycobacterium tuberculosis: Comparison of Structures and Catalytic Activities of RipA and RipB.
J.Mol.Biol., 413:247-260, 2011

PubMed Abstract: The success of Mycobacterium tuberculosis in sustaining long-term survival within the host macrophages partly relies on its unique cell envelop that also confers low susceptibility to several antibiotics. Remodeling of the septal peptidoglycan (PG) has been linked to the putative PG hydrolases RipA and RipB. The crystal structures of RipB (Rv1478) and the homologous module of RipA (Rv1477) were determined to 1.60 Å and 1.38 Å resolution, respectively. Both proteins contain a C-terminal core domain resembling the NlpC-type PG hydrolases. However, the structure of RipB exhibits striking differences to the structures of this domain in RipA reported here and previously by others. Major structural differences were found in the N-terminal segments of 70 amino acids and in an adjacent loop, which form part of the substrate binding groove. Both RipA and RipB are able to bind PG. RipA, its C-terminal module and RipB cleave defined PG fragments between d-glutamate and meso-diaminopimelate with pH optima of 5 and 6, respectively. The peptidase module of RipA is also able to degrade Bacillus subtilis PG, which displays peptide stems and cross-links identical with those found in mycobacterial murein. RipB did not show comparable hydrolase activity with this substrate. Removal of the N-terminal segments previously suggested to have a role in auto-inhibition did not change the activity of either RipA or RipB. A comparison of the putative active-site clefts in the two enzymes provides structural insights into the basis of the differences in their substrate specificity.

PubMed: 21864539
DOI: 10.1016/j.jmb.2011.08.014

実験手法

X-RAY DIFFRACTION (1.38 Å)