Disease relevance of guanidine

• The proteins of visna are separated into nine major peaks by agarose gel chromatography in 6 M guanidine hydrochloride (GuHCl) [1].
• This single-chain immunotoxin was expressed in E. coli and purified under denaturing condition of 6M guanidine hydrochloride (GuHCl) [2].

High impact information on guanidine

• We found that low concentrations of guanidine hydrochloride (GdnHCl, <0.75 M) or urea (<1.5 M) enhanced the enzyme activity of lipocalin-type prostaglandin (PG) D synthase (L-PGDS) maximally 2.5- and 1.6-fold at 0.5 M GdnHCl and 1 M urea, respectively [3].
• The intensity of the circular dichroism (CD) spectrum at 218 nm, reflecting the beta-sheet content, was also increased by either denaturant in a concentration-dependent manner, with the maximum at 0.5 M GdnHCl or 1 M urea [3].
• First, provided that the refolding conditions are identical, the two denatured states fold with very similar kinetics, despite the fact the extensive secondary structure is present in the TFE-denatured state but not in the protein denatured in 6 M GuHCl [4].
• By contrast, binding to chromatin from zone III (containing spermatozoa and little or no detectable receptor) showed no major peak and 4 times less binding at 3 M GuHCl-extracted chromatin [5].
• In 1 M GdnHCl, the stability of IFN-gamma was greatly reduced and much less protection from HX in solution was observed [6].

Anatomical context of guanidine

• When PEG was used in the dilution buffer, aggregation of rhDNAse did not occur during refolding in either case. rhtPA produced from CHO cells was denatured in 5 M guanidine hydrochloride (GuHCl) and refolded by rapid dilution to 0.10 M GuHCl and 0.20 mg/ml protein.(ABSTRACT TRUNCATED AT 250 WORDS)[7]

Associations of guanidine with other chemical compounds

• These results show that helix C, which forms the hydrophobic core of the IFN-gamma dimer, is highly protected from HX under native conditions, is more stable in GdnHCl than the rest of the protein and remains intact in both GdnHCl- and KSCN-induced aggregates [6].
• Previous folding studies of alpha-1-proteinase inhibitor (alpha1-PI), which regulates the activity of the serine protease human neutrophil elastase, show an intermediate state at approximately 1.5 M guanidine-HCl (Gu) [8].

Gene context of guanidine

• By plotting the enzyme activities against the ellipticities at 218 nm of the CD spectra of L-PGDS in the presence or absence of GdnHCl or urea, we found two states in the reversible folding process of L-PGDS: one is an activity-enhanced state and the other, an inactive state [3].
• Citrate synthase (CS), which has been denatured in either guanidine hydrochloride (GdnHCl) or urea can be assisted in its renaturation in a variety of ways [9].
• From kinetic unfolding experiments in 5 M GdnHCl it was determined that the conversion of M1 to M2 had an activation energy of 26.5 kcal/mol, a half-life of 23 h at 25 degrees C, and the rate of formation of M2 was dependent on the GdnHCl concentration between 5 and 7.1 M GdnHCl [10].

Analytical, diagnostic and therapeutic context of guanidine

• The patterns of SDS-PAGE show that the excluded material from the GuHCl column contains an aggregate of 10 non-glycosylated polypeptides [1].
• Unfolding was studied by destabilizing the protein in guanidine hydrochloride (GdHCl) or urea, pulse-labeling with 2H2O and analyzing the intact protein by HPLC electrospray ionization mass spectrometry [11].

References