Functional role of the N-terminal region of the Lon protease from Mycobacterium smegmatis.

  title={Functional role of the N-terminal region of the Lon protease from Mycobacterium smegmatis.},
  author={S G Roudiak and Thomas E. Shrader},
  volume={37 32},
Lon protease homologues contain a poorly conserved N-terminal region of variable length. To better understand the role of the N-terminal region of Lon in the complicated reaction cycle of ATP-dependent protein degradation, we expressed and characterized mutants of the Lon protease from Mycobacterium smegmatis (Ms-Lon) lacking 90, 225, and 277 N-terminal residues (N-G91, N-E226, and N-I278, respectively). N-I278 displayed neither peptidase nor ATPase activity despite the fact that it was stable… 

The N-terminal substrate-recognition domain of a LonC protease exhibits structural and functional similarity to cytosolic chaperones.

The crystal structure of the N-terminal AAA-like α/β subdomain of MtaLonC containing an intact LID, which forms a large α-helical hairpin protruding from theAAA-like domain, is reported and is shown that the LID of LonC is involved both in Skp-like chaperone activity and in recognition of unfolded protein substrates.

Crystal structure of XCC3289 from Xanthomonas campestris: homology with the N-terminal substrate-binding domain of Lon peptidase.

The structure of XCC3289 closely resembles those of the N-terminal domains of the LonA peptidases from Escherichia coli and Mycobacterium avium, and the structure is also similar to that of cereblon, a substrate-recognizing component of the E3 ubiquitin ligase complex.

Functional Domains of Brevibacillus thermoruber Lon Protease for Oligomerization and DNA Binding

The results show that the N-terminal domain is essential for oligomerization of Bt-Lon, and that the SSD is involved in DNA binding based on gel mobility shift assays and ionic interactions are mainly responsible for the assembly of hexamers.

Structure of the N-terminal fragment of Escherichia coli Lon protease.

The structure of a recombinant construct consisting of residues 1-245 of Escherichia coli Lon protease, the prototypical member of the A-type Lon family, is reported and compared with the structures of the putative substrate-binding domains of several proteins, showing topological similarities that should help in defining the binding sites used by Lon substrates.

Influence of the (1–106) fragment of Escherichia coli Lon protease on the enzyme function and DNA binding

It has been shown that the fragment does not affect the enzyme peptidase site function or the hydrolysis of the protein substrate by the processive mechanism, and is essential for the manifestation of proper ATPase activity and for the implementation of the conformational rearrangements in the ATPase domain.

New insights into structural and functional relationships between LonA proteases and ClpB chaperones

The hypothesis that there is a structural and functional relationship between two coiled–coil fragments and implies a similar mechanism of engagement of the pore‐1 loops in the AAA+ modules of LonAs and ClpBs is supported.

Crystal structure of the N‐terminal domain of E. coli Lon protease

The first crystal structure of the N‐terminal domain of an A‐type Lon protease is reported, and it is postulate that, as is the case in Lon proteases, this structural domain represents a general protein and polypeptide interaction domain.