A comparative study of the unfolding thermodynamics of vertebrate metmyoglobins.


Abstract

Differential scanning microcalorimetry (DSC) of horse, rat, opossum, raccoon, carp, and armadillo metmyoglobins at alkaline pH gave data that fit the two-state unfolding model well. Monte Carlo studies were used to assess the impact of truncating DSC scans on the reliability of the calculated results when aggregation exotherms overlapped the unfolding endotherm at the high-temperature end of the scan. The DSC estimates for the conformational free energy at pH 8 and 298 K are compared to earlier results from isothermal acid and guanidinium chloride unfolding. Stability estimates at pH 8 for these six metmyoglobins obtained by DSC experiments do not agree with free energy estimates at pH 8 from guanidinium chloride unfolding. This is true for all three models used to extrapolate the free energy change to 0 M guanidinium chloride. Among these six myoglobins, significant variation appears in the temperature at which the myoglobin is half-unfolded, in the change in heat capacity upon unfolding, and in the change in enthalpy at 310 K. Calculations made with the hydrophobic model for protein folding [Baldwin, R.L. (1986) Proc. Natl. Acad. Sci. U.S.A. 83, 8069] suggest that a sizable variation exists for that portion of the unfolding enthalpy change assigned to forces other than the hydrophobic effect. Study holds ProTherm entries: 3713, 3714, 3715, 3716, 3717, 3718, 3719, 3720, 3721, 3722, 3723, 3724, 3725, 3726, 3727, 3728, 3729, 3730, 3731, 3732, 3733, 3734, 3735, 3736, 3737, 3738, 3739, 3740, 3741, 3742, 3743, 3744, 3745, 3746, 3747, 3748, 3749, 3750, 3751, 3752, 3753, 3754, 3755, 3756, 3757, 3758, 3759, 3760, 3761, 3762, 3763, 3764, 3765, 3766, 3767, 3768, 3769, 3770, 3771, 3772, 3773, 3774, 3775, 3776, 3777 Extra Details: two-state unfolding model; monte Carlo studies;,hydrophobic model; unfolding endotherm; sizable variation

Submission Details

ID: tcw8pnK63

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:22 p.m.

Version: 1

Publication Details
Kelly L;Holladay LA,Biochemistry (1990) A comparative study of the unfolding thermodynamics of vertebrate metmyoglobins. PMID:2378866
Additional Information

Study Summary

Number of data points 191
Proteins Myoglobin ; Myoglobin ; Myoglobin ; Myoglobin ; Myoglobin
Unique complexes 4
Assays/Quantities/Protocols Experimental Assay: dCp pH:9.56 ; Experimental Assay: dHcal pH:9.56 ; Experimental Assay: Tm pH:9.56 ; Experimental Assay: dCp pH:10.0 ; Experimental Assay: dHcal pH:10.0 ; Experimental Assay: Tm pH:10.0 ; Experimental Assay: dCp pH:10.39 ; Experimental Assay: dHcal pH:10.39 ; Experimental Assay: Tm pH:10.39 ; Experimental Assay: dCp pH:10.55 ; Experimental Assay: dHcal pH:10.55 ; Experimental Assay: Tm pH:10.55 ; Experimental Assay: dCp pH:10.66 ; Experimental Assay: dHcal pH:10.66 ; Experimental Assay: Tm pH:10.66 ; Experimental Assay: dCp pH:10.92 ; Experimental Assay: dHcal pH:10.92 ; Experimental Assay: Tm pH:10.92 ; Experimental Assay: dCp pH:11.18 ; Experimental Assay: dHcal pH:11.18 ; Experimental Assay: Tm pH:11.18 ; Experimental Assay: dCp pH:11.49 ; Experimental Assay: dHcal pH:11.49 ; Experimental Assay: Tm pH:11.49 ; Experimental Assay: dCp pH:9.9 ; Experimental Assay: dHcal pH:9.9 ; Experimental Assay: Tm pH:9.9 ; Experimental Assay: dCp pH:10.01 ; Experimental Assay: dHcal pH:10.01 ; Experimental Assay: Tm pH:10.01 ; Experimental Assay: dCp pH:10.32 ; Experimental Assay: dHcal pH:10.32 ; Experimental Assay: Tm pH:10.32 ; Experimental Assay: dCp pH:10.72 ; Experimental Assay: dHcal pH:10.72 ; Experimental Assay: Tm pH:10.72 ; Experimental Assay: dCp pH:10.83 ; Experimental Assay: dHcal pH:10.83 ; Experimental Assay: Tm pH:10.83 ; Experimental Assay: dCp pH:11.2 ; Experimental Assay: dHcal pH:11.2 ; Experimental Assay: Tm pH:11.2 ; Experimental Assay: Tm pH:9.44 ; Experimental Assay: dCp pH:9.87 ; Experimental Assay: dHcal pH:9.87 ; Experimental Assay: Tm pH:9.87 ; Experimental Assay: dCp pH:10.14 ; Experimental Assay: dHcal pH:10.14 ; Experimental Assay: Tm pH:10.14 ; Experimental Assay: dCp pH:10.34 ; Experimental Assay: dHcal pH:10.34 ; Experimental Assay: Tm pH:10.34 ; Experimental Assay: dCp pH:10.76 ; Experimental Assay: dHcal pH:10.76 ; Experimental Assay: Tm pH:10.76 ; Experimental Assay: dCp pH:11.15 ; Experimental Assay: dHcal pH:11.15 ; Experimental Assay: Tm pH:11.15 ; Experimental Assay: dCp pH:11.55 ; Experimental Assay: dHcal pH:11.55 ; Experimental Assay: Tm pH:11.55 ; Experimental Assay: dCp pH:11.69 ; Experimental Assay: dHcal pH:11.69 ; Experimental Assay: Tm pH:11.69 ; Experimental Assay: dCp pH:11.77 ; Experimental Assay: dHcal pH:11.77 ; Experimental Assay: Tm pH:11.77 ; Experimental Assay: dCp pH:8.0 ; Experimental Assay: dHcal pH:8.0 ; Experimental Assay: Tm pH:8.0 ; Experimental Assay: dCp pH:9.94 ; Experimental Assay: dHcal pH:9.94 ; Experimental Assay: Tm pH:9.94 ; Experimental Assay: dCp pH:10.15 ; Experimental Assay: dHcal pH:10.15 ; Experimental Assay: Tm pH:10.15 ; Experimental Assay: dCp pH:10.36 ; Experimental Assay: dHcal pH:10.36 ; Experimental Assay: Tm pH:10.36 ; Experimental Assay: dCp pH:10.71 ; Experimental Assay: dHcal pH:10.71 ; Experimental Assay: Tm pH:10.71 ; Experimental Assay: dCp pH:11.27 ; Experimental Assay: dHcal pH:11.27 ; Experimental Assay: Tm pH:11.27 ; Experimental Assay: dCp pH:11.6 ; Experimental Assay: dHcal pH:11.6 ; Experimental Assay: Tm pH:11.6 ; Experimental Assay: dCp pH:11.85 ; Experimental Assay: dHcal pH:11.85 ; Experimental Assay: Tm pH:11.85 ; Experimental Assay: dCp pH:11.97 ; Experimental Assay: dHcal pH:11.97 ; Experimental Assay: Tm pH:11.97 ; Experimental Assay: dCp pH:9.99 ; Experimental Assay: dHcal pH:9.99 ; Experimental Assay: Tm pH:9.99 ; Experimental Assay: dCp pH:10.18 ; Experimental Assay: dHcal pH:10.18 ; Experimental Assay: Tm pH:10.18 ; Experimental Assay: dCp pH:10.37 ; Experimental Assay: dHcal pH:10.37 ; Experimental Assay: Tm pH:10.37 ; Experimental Assay: dCp pH:10.59 ; Experimental Assay: dHcal pH:10.59 ; Experimental Assay: Tm pH:10.59 ; Experimental Assay: dCp pH:10.87 ; Experimental Assay: dHcal pH:10.87 ; Experimental Assay: Tm pH:10.87 ; Experimental Assay: dCp pH:11.09 ; Experimental Assay: dHcal pH:11.09 ; Experimental Assay: Tm pH:11.09 ; Experimental Assay: dCp pH:11.1 ; Experimental Assay: dHcal pH:11.1 ; Experimental Assay: Tm pH:11.1 ; Experimental Assay: dCp pH:11.92 ; Experimental Assay: dHcal pH:11.92 ; Experimental Assay: Tm pH:11.92 ; Experimental Assay: dCp pH:11.96 ; Experimental Assay: dHcal pH:11.96 ; Experimental Assay: Tm pH:11.96 ; Experimental Assay: Tm pH:9.52 ; Experimental Assay: dCp pH:9.63 ; Experimental Assay: dHcal pH:9.63 ; Experimental Assay: Tm pH:9.63 ; Experimental Assay: dCp pH:9.98 ; Experimental Assay: dHcal pH:9.98 ; Experimental Assay: Tm pH:9.98 ; Experimental Assay: dCp pH:10.38 ; Experimental Assay: dHcal pH:10.38 ; Experimental Assay: Tm pH:10.38 ; Experimental Assay: dCp pH:10.65 ; Experimental Assay: dHcal pH:10.65 ; Experimental Assay: Tm pH:10.65 ; Experimental Assay: dCp pH:10.97 ; Experimental Assay: dHcal pH:10.97 ; Experimental Assay: Tm pH:10.97 ; Experimental Assay: dCp pH:11.19 ; Experimental Assay: dHcal pH:11.19 ; Experimental Assay: Tm pH:11.19 ; Experimental Assay: dCp pH:11.5 ; Experimental Assay: dHcal pH:11.5 ; Experimental Assay: Tm pH:11.5 ; Experimental Assay: dCp pH:9.13 ; Experimental Assay: dHcal pH:9.13 ; Experimental Assay: Tm pH:9.13
Libraries Mutations for sequence GLSDGEWQQVLNVWGKVEADIAGHGQEVLIRLFTGHPETLEKFDKFKHLKTEAEMKASEDLKKHGTVVLTALGGILKKKGHHEAELKPLAQSHATKHKIPIKYLEFISDAIIHVLHSKHPGDFGADAQGAMTKALELFRNDIAAKYKELGFQG ; Mutations for sequence MGLSDGEWQLVLNVWGKVEGDLAGHGQEVLIKLFKNHPETLEKFDKFKHLKSEDEMKGSEDLKKHGNTVLTALGGILKKKGQHAAEIQPLAQSHATKHKIPIKYLEFISEAIIQVLQSKHPGDFGADAQGAMSKALELFRNDIAAKYKELGFQG ; Mutations for sequence MGLSDGEWQLVLNAWGKVEADIPGHGQEVLIRLFKGHPETLEKFDKFKHLKSEDEMKASEDLKKHGATVLTALGNILKKKGNHEAELKPLAQSHATKHKISVQFLEFISEAIIQVIQSKHPGDFGGDAQAAMGKALELFRNDMAAKYKELGFQG ; Mutations for sequence MHDAELVLKCWGGVEADFEGTGGEVLTRLFKQHPETQKLFPKFVGIASNELAGNAAVKAHGATVLKKLGELLKARGDHAAILKPLATTHANTHKIALNNFRLITEVLVKVMAEKAGLDAGGQSALRRVMDVVIGDIDTYYKEIGFAG

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
3RGK 2011-04-08T00:00:00+0000 1.65 Crystal Structure of Human Myoglobin Mutant K45R
5YCI 2017-09-07T00:00:00+0000 1.97 Ancestral myoglobin aMbWb' of Basilosaurus relative (polyphyly)
5YCJ 2017-09-07T00:00:00+0000 1.58 Ancestral myoglobin aMbWb' of Basilosaurus relative (polyphyly) imidazole-ligand
1M6C 1998-08-12T00:00:00+0000 1.9 V68N MYOGLOBIN WITH CO
1M6M 1998-08-13T00:00:00+0000 1.8 V68N MET MYOGLOBIN
1MDN 1998-08-12T00:00:00+0000 1.98 WILD TYPE MYOGLOBIN WITH CO
1MNH 1995-01-11T00:00:00+0000 2.3 INTERACTIONS AMONG RESIDUES CD3, E7, E10 AND E11 IN MYOGLOBINS: ATTEMPTS TO SIMULATE THE O2 AND CO BINDING PROPERTIES OF APLYSIA MYOGLOBIN
1MNI 1995-01-11T00:00:00+0000 2.07 ALTERATION OF AXIAL COORDINATION BY PROTEIN ENGINEERING IN MYOGLOBIN. BIS-IMIDAZOLE LIGATION IN THE HIS64-->VAL(SLASH)VAL68-->HIS DOUBLE MUTANT
1MNJ 1995-01-11T00:00:00+0000 2.2 INTERACTIONS AMONG RESIDUES CD3, E7, E10 AND E11 IN MYOGLOBINS: ATTEMPTS TO SIMULATE THE O2 AND CO BINDING PROPERTIES OF APLYSIA MYOGLOBIN
1MNK 1995-01-11T00:00:00+0000 2.2 INTERACTIONS AMONG RESIDUES CD3, E7, E10 AND E11 IN MYOGLOBINS: ATTEMPTS TO SIMULATE THE O2 AND CO BINDING PROPERTIES OF APLYSIA MYOGLOBIN

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
90.3 Myoglobin P02170 MYG_RABIT
90.3 Myoglobin C0HKB7 MYG_SCIVU
90.3 Myoglobin P02157 MYG_MELME
90.3 Myoglobin P02156 MYG_ERIEU
90.3 Myoglobin P02164 MYG_ORYAF
90.9 Myoglobin P20856 MYG_CTEGU
92.2 Myoglobin P02163 MYG_ROUAE
91.6 Myoglobin P04250 MYG_LAGMA
91.6 Myoglobin C0HJQ9 MYG_HYSCR
92.2 Myoglobin Q6PL31 MYG_OCHCU
92.9 Myoglobin P02165 MYG_TUPGL
92.9 Myoglobin P02189 MYG_PIG
92.9 Myoglobin P04249 MYG_PROGU
93.5 Myoglobin P02171 MYG_OCHPR
94.2 Myoglobin P11343 MYG_LUTLU
100.0 Myoglobin P04248 MYG_SPAEH
90.3 Myoglobin P02150 MYG_MACFA
90.3 Myoglobin P02144 MYG_HUMAN
90.9 Myoglobin P68085 MYG_SEMEN
90.9 Myoglobin P68084 MYG_PAPAN
90.9 Myoglobin P68086 MYG_ERYPA
100.0 Myoglobin P02193 MYG_DIDVI
100.0 Myoglobin P02204 MYG_CYPCA
90.3 Myoglobin P02167 MYG_NYCCO
90.3 Myoglobin Q0KIY0 MYG_MESST
90.3 Myoglobin P02183 MYG_MESCA
90.8 Myoglobin P02177 MYG_ESCRO
90.8 Myoglobin Q0KIY2 MYG_BALED
90.8 Myoglobin Q0KIY1 MYG_BALBO
90.9 Myoglobin P02166 MYG_PERPO
92.2 Myoglobin P02169 MYG_LEPMU
91.6 Myoglobin P02181 MYG_INIGE
100.0 Myoglobin P68082 MYG_HORSE
100.0 Myoglobin P68083 MYG_EQUBU
90.1 Myoglobin P02178 MYG_MEGNO