4Q4G

Structure of the Resuscitation Promoting Factor Interacting protein RipA mutated at C383

Summary for 4Q4G

• Entry DOI: 10.2210/pdb4q4g/pdb
• Related: 4Q4N 4Q4T
• Descriptor: Peptidoglycan endopeptidase RipA (2 entities in total)
• Functional Keywords: alpha-beta, cell wall hydrolase, hydrolase
• Biological source: Mycobacterium tuberculosis
• Cellular location: Secreted: O53168
• Total number of polymer chains: 1
• Total formula weight: 49828.80

Authors

Berisio, R. (deposition date: 2014-04-14, release date: 2014-09-10, Last modification date: 2024-02-28)

Primary citation

Squeglia, F.,Ruggiero, A.,Romano, M.,Vitagliano, L.,Berisio, R.
Mutational and structural study of RipA, a key enzyme in Mycobacterium tuberculosis cell division: evidence for the L-to-D inversion of configuration of the catalytic cysteine.
Acta Crystallogr.,Sect.D, 70:2295-2300, 2014

PubMed Abstract: RipA is a key cysteine protease of Mycobacterium tuberculosis as it is responsible for bacterial daughter-cell separation. Although it is an important target for antimicrobial development, its mechanism of action and its interaction pattern with its substrate are hitherto unknown. By combining crystallographic and mutational studies with functional assays and molecular modelling, it is shown that the catalytic activity of the enzyme relies on a Cys-His-Glu triad and the impact of the mutation of each residue of the triad on the structure and function of RipA is analysed. Unexpectedly, the crystallographic analyses reveal that mutation of the glutamic acid to alanine results in inversion of the configuration of the catalytic cysteine. The consequent burial of the catalytic cysteine side chain explains the enzyme inactivation upon mutation. These data point to a novel role of the acidic residue often present in the triad of cysteine proteases as a supervisor of cysteine configuration through preservation of the local structural integrity.

PubMed: 25195744
DOI: 10.1107/S1399004714013674

Experimental method

X-RAY DIFFRACTION (0.97 Å)