The conformational stability and flexibility of insulin with an additional intramolecular cross-link.


The conformational stability and flexibility of insulin containing a cross-link between the alpha-amino group of the A-chain to the epsilon-amino group of Lys29 of the B-chain was examined. The cross-link varied in length from 2 to 12 carbon atoms. The conformational stability was determined by guanidine hydrochloride-induced equilibrium denaturation and flexibility was assessed by H2O/D2O amide exchange. The cross-link has substantial effects on both conformational stability and flexibility which depend on its length. In general, the addition of a cross-link enhances conformational stability and decreases flexibility. The optimal length for enhanced stability and decreased flexibility was the 6-carbon link. For the 6-carbon link the Gibbs free energy of unfolding was 8.0 kcal/mol compared to 4.5 kcal/mol for insulin, and the amide exchange rate decreased by at least 3-fold. A very short cross-link (i.e. the 2-carbon link) caused conformational strain that was detectable by a lack of stabilization in the Gibbs free energy of unfolding and enhancement in the amide exchange rate compared to insulin. The effect of the cross-link length on insulin hydrodynamic properties is discussed relative to previously obtained receptor binding results. Study holds ProTherm entries: 5157 Extra Details: additive : EDTA(1 mM), conformational stability; flexibility; H2O/D2O amide exchange;,hydrodynamic properties; receptor binding

Submission Details

ID: 8t5hLSwC

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:28 p.m.

Version: 1

Publication Details
Brems DN;Brown PL;Nakagawa SH;Tager HS,J. Biol. Chem. (1991) The conformational stability and flexibility of insulin with an additional intramolecular cross-link. PMID:1988440
Additional Information

Study Summary

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 UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
200.0 A,B Insulin P01315 INS_PIG
200.0 A,B Insulin P67973 INS_BALPH
200.0 A,B Insulin P01321 INS_CANLF
200.0 A,B Insulin P30407 INS_CHLAE
200.0 A,B Insulin Q6YK33 INS_GORGO
200.0 A,B Insulin P01308 INS_HUMAN
196.7 A,B Insulin Q91XI3 INS_ICTTR
200.0 A,B Insulin P30406 INS_MACFA
200.0 A,B Insulin P30410 INS_PANTR
200.0 A,B Insulin P67974 INS_PHYMC
200.0 A,B Insulin Q8HXV2 INS_PONPY
196.7 A,B Insulin P01311 INS_RABIT
95.2 A Insulin P01325 INS1_MOUSE
95.2 A Insulin P01322 INS1_RAT
191.60000000000002 A,B Insulin P01326 INS2_MOUSE
191.60000000000002 A,B Insulin P01323 INS2_RAT
188.5 A,B Insulin P01324 INS_ACOCA
191.9 A,B Insulin P01313 INS_CRILO
195.2 A,B Insulin P01310 INS_HORSE
195.2 A,B Insulin Q62587 INS_PSAOB
190.5 A,B Insulin P01316 INS_ELEMA
190.5 A,B Insulin P01317 INS_BOVIN
187.2 A,B Insulin P01320 INS_CAMDR
90.5 A Insulin P01327 INS_CHICH
190.5 A,B Insulin P01314 INS_BALBO
190.5 A,B Insulin P18109 INS_DIDVI
100.0 B Insulin P01319 INS_CAPHI
100.0 B Insulin P06306 INS_FELCA
100.0 B Insulin P01318 INS_SHEEP
100.0 B Insulin F8WCM5 INSR2_HUMAN
96.6 B Insulin P51463 INS_SELRF
96.4 B Insulin P67970 INS_CHICK
96.4 B Insulin P67968 INS_MELGA
96.4 B Insulin P67969 INS_STRCA
96.4 B Insulin P69047 INS_TRADO
96.4 B Insulin P69048 INS_TRASC
93.1 B Insulin P67972 INS_AOTTR
93.1 B Insulin P67971 INS_SAISC
96.3 B Insulin P01333 INS_ANAPL
96.3 B Insulin P68245 INS_ANSAN
96.3 B Insulin P68243 INS_CAIMO
92.9 B Insulin P12706 INS1_XENLA
93.3 B Insulin P83770 INSL_VIGUN
100.0 B Insulin P81423 INS_ACIGU
96.6 B Insulin P21563 INS_RODSP
96.2 B Insulin C0HJI8 INS2_HUSDA
92.6 B Insulin P12707 INS2_XENLA
92.6 B Insulin P01340 INS_KATPE
92.3 B Insulin P04667 INS_ONCKE
92.3 B Insulin P09477 INS_PLAFE
92.3 B Insulin Q9W7R2 INS_VERMO
92.3 B Insulin P09476 INS_ATRSP
92.3 B Insulin C0HJI3 INS2_KATPE
92.6 B Insulin C0HJI7 INS1_HUSDA
91.7 B Insulin P68988 INS_LAMFL
91.7 B Insulin P68987 INS_PETMA
91.3 B Insulin P01338 INS2_BATSP