1LNI: Crystal Structure Analysis Of A Ribonuclease From Streptomyces Aureofaciens At Atomic Resolution (1.0 A)

Ribonuclease from Streptomyces aureofaciens, the bacterial source for the industrial production of chlorotetracycline, is a guanylate endoribonuclease (RNase Sa; EC which hydrolyses the phosphodiester bonds of single-stranded RNA at the 3'-side of guanosine nucleotides with high specificity. The structure of the enzyme was previously refined at atomic resolution (1.2 A) using room-temperature data. Here, the RNase Sa structure refined against 1.0 A data collected at cryogenic temperature is reported. There are two surface loops in molecule A and one in molecule B for which two main-chain conformations are modelled: these loops contain active-site residues. The separation for most of the corresponding main-chain atoms in the two conformations is about 0.8 A, with a maximum of 2.5 A. The two regions of dual conformation represent the most important differences in comparison with the structure determined at room temperature, where the corresponding loops have one conformation only but the largest degree of anisotropy. The flexibility of the loops observed in the structure of RNase Sa is directly linked to the need for the active site to interact productively with substrates and/or inhibitors.
PDB ID: 1LNIDownload
MMDB ID: 20249
PDB Deposition Date: 2002/5/3
Updated in MMDB: 2017/11
Experimental Method:
x-ray diffraction
Resolution: 1  Å
Source Organism:
Similar Structures:
Biological Unit for 1LNI: monomeric; determined by author
Molecular Components in 1LNI
Label Count Molecule
Protein (1 molecule)
Guanyl-specific Ribonuclease SA
Molecule annotation
Chemicals (3 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB