Stabilization of human pancreatic ribonuclease through mutation at its N-terminal edge.


Enzyme stability can be an important parameter in the design of recombinant toxins because unstable proteins are often degraded before they can reach their cellular target. There is great interest in the design of human pancreatic ribonuclease variants that could be cytotoxic against tumoral cells. To this end, some residues in the protein need to be substituted, but this may result in a loss of stability. Previous papers have reported the production of N- and C-terminal human pancreatic ribonuclease variants with increased thermal stability. Here, we investigated the contribution of the different amino acid changes at the N-terminus of the protein to its thermostability increase. We show that this increase correlates with the helical propensity of the first alpha-helix of the protein. On the other hand, deletion of the four last residues of the protein does not affect its thermal stability. These results set the basis for the design of a human pancreatic ribonuclease template on which amino acid substitutions can be made that could render the enzyme cytotoxic, without an important loss in its stability. Study holds ProTherm entries: 15521, 15522, 15523, 15524, 15525, 15526, 15527 Extra Details: one additional Met was added at the C-terminal helicity; human pancreatic ribonuclease; site-directed mutagenesis; thermal stability

Submission Details


Submitter: Connie Wang

Submission Date: April 24, 2018, 8:46 p.m.

Version: 1

Publication Details
Benito A;Bosch M;Torrent G;Ribó M;Vilanova M,Protein Eng. (2002) Stabilization of human pancreatic ribonuclease through mutation at its N-terminal edge. PMID:12538908
Additional Information

Structure view and single mutant data analysis

Study data

No weblogo for data of varying length.
Colors: D E R H K S T N Q A V I L M F Y W C G P

Data Distribution

Studies with similar sequences (approximate matches)

Correlation with other assays (exact sequence matches)

Relevant PDB Entries

Structure ID Release Date Resolution Structure Title
1DZA 2000-02-21T00:00:00+0000 1.65 3-D structure of a HP-RNase
1E21 2000-05-15T00:00:00+0000 1.9 Ribonuclease 1 des1-7 Crystal Structure at 1.9A
1H8X 2001-02-16T00:00:00+0000 2.0 Domain-swapped Dimer of a Human Pancreatic Ribonuclease Variant
1Z7X 2005-03-28T00:00:00+0000 1.95 X-ray structure of human ribonuclease inhibitor complexed with ribonuclease I
2E0J 2006-10-10T00:00:00+0000 1.6 Mutant Human Ribonuclease 1 (R31L, R32L)
2E0L 2006-10-10T00:00:00+0000 1.6 Mutant Human Ribonuclease 1 (Q28L, R31L, R32L)
2E0M 2006-10-10T00:00:00+0000 1.7 Mutant Human Ribonuclease 1 (T24L, Q28L, R31L, R32L)
2E0O 2006-10-10T00:00:00+0000 2.0 Mutant Human Ribonuclease 1 (V52L, D53L, N56L, F59L)
2K11 2008-02-20T00:00:00+0000 0 Solution structure of human pancreatic ribonuclease
2Q4G 2007-05-31T00:00:00+0000 1.95 Ensemble refinement of the protein crystal structure of human ribonuclease inhibitor complexed with ribonuclease I

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
90.6 Ribonuclease pancreatic Q8SQ07 RNAS1_SAGOE
90.6 Ribonuclease pancreatic Q8SQ06 RNAS1_ATEGE
91.4 Ribonuclease pancreatic Q8SQ08 RNAS1_SAISC
93.8 Ribonuclease pancreatic Q8SPN4 RNAS1_PYGNE
95.5 Ribonuclease pancreatic Q8SQ12 RNAS1_PONPY
97.7 Ribonuclease pancreatic Q8SQ11 RNAS1_NOMLE
97.7 Ribonuclease pancreatic Q8SQ14 RNAS1_PANTR
97.7 Ribonuclease pancreatic Q8SQ13 RNAS1_GORGO
100.0 Ribonuclease pancreatic P07998 RNAS1_HUMAN
92.1 Ribonuclease pancreatic Q8SQ09 RNAS1_PAPHA
92.1 Ribonuclease pancreatic Q8SPN5 RNAS1_MACMU
92.9 Ribonuclease pancreatic P61822 RNAS1_MIOTA
92.9 Ribonuclease pancreatic P61821 RNAS1_CHLAE