THE STRUCTURE AT 1.8 ANGSTROMS RESOLUTION OF A SINGLE SITE MUTANT (T189I) OF MALATE DEHYDROGENASE FROM THERMUS FLAVUS WITH INCREASED ENZYMATIC ACTIVITY

BETA-6-HYDROXY-1,4,5,6-TETRHYDRONICOTINAMIDE ADENINE DINUCLEOTIDE

Determinants of protein thermostability observed in the 1.9-A crystal structure of malate dehydrogenase from the thermophilic bacterium Thermus flavus.

Preliminary X-Ray Diffraction Analysis of a Crystallizable Mutant of Malate Dehydrogenase from the Thermophile Thermus Flavus

Role of Threonine 190 in Modulating the Catalytic Function of Malate Dehydrogenase from a Thermophile Thermus Flavus

Refined Crystal Structure of Cytoplasmic Malate Dehydrogenase at 2.5-Angstroms Resolution

Nucleotide Sequence of the Malate Dehydrogenase Gene of Thermus Flavus and its Mutation Directing an Increase in Enzyme Activity

Chemistry and Solution Conformation of the Pyridine Coenzymes

MKAPVRVAVTGAAGQIGYSLLFRIAAGEMLGKDQPVILQLLEIPQAMKALEGVVMELEDCAFPLLAGLEATDDPDVAFKD
ADYALLVGAAPRKAGMERRDLLQVNGKIFTEQGRALAEVAKKDVKVLVVGNPANTNALIAYKNAPGLNPRNFTAMTRLDH
NRAKAQLAKKTGTGVDRIRRMTVWGNHSSIMFPDLFHAEVDGRPALELVDMEWYEKVFIPTVAQRGAAIIQARGASSAAS
AANAAIEHIRDWALGTPEGDWVSMAVPSQGEYGIPEGIVYSFPVTAKDGAYRVVEGLEINEFARKRMEITAQELLDEMEQ
VKALGLI

WHILE THE ENZYME WAS CRYSTALLIZED AT PH 7.5 IN THE PRESENCE OF THE REDUCED COENZYME NADH, THE ELECTRON DENSITY MAP WAS BEST FIT BY THE MODIFIED COENZYME REFERRED TO AS NADHX.

THE NUMBERING SYSTEM IS THE SAME AS THAT USED FOR THE
CYTOPLASMIC MALATE DEHYDROGENASE STRUCTURE. THE DELETION
REGIONS IN TMDH-T189I, 201 - 204, 213 AND 276, LEAD TO
DISCONTINUITIES IN THE TMDH NUMBERING; HOWEVER, THESE DO
NOT REPRESENT BREAKS IN THE PEPTIDE CHAIN.

SEQUENCE ADVISORY NOTICE
DIFFERENCE BETWEEN SWISS-PROT AND PDB SEQUENCE.

SWISS-PROT ENTRY NAME: MDH_THEFL

SWISS-PROT RESIDUE PDB SEQRES

NAME NUMBER NAME CHAIN SEQ/INSERT CODE
LYS 75 ASP A 74

CROSS REFERENCE TO SEQUENCE DATABASE
SWISS-PROT ENTRY NAME PDB ENTRY CHAIN NAME
MDH_THEFL B

SEQUENCE ADVISORY NOTICE
DIFFERENCE BETWEEN SWISS-PROT AND PDB SEQUENCE.

SWISS-PROT ENTRY NAME: MDH_THEFL

SWISS-PROT RESIDUE PDB SEQRES

NAME NUMBER NAME CHAIN SEQ/INSERT CODE
LYS 75 ASP B 74

THE SEQUENCE PRESENTED IN THE ENTRY FITS THE OBSERVED
DENSITY BETTER THAN THE PUBLISHED SEQUENCE.

THE ASYMMETRIC UNIT CONTAINS TWO SUBUNITS WHICH HAVE BEEN ASSIGNED CHAIN IDENTIFIERS *A* AND *B*. THEY ARE RELATED BY A NON-CRYSTALLOGRAPHIC SYMMETRY AXIS WITH A ROTATION ANGLE OF 180.0 DEGREES. THE TRANSFORMATION PROVIDED ON THE *MTRIX* RECORDS BELOW YIELDS OPTIMAL SUPERPOSITION OF SUBUNIT A UPON SUBUNIT B BASED UPON ALL ALPHA CARBON ATOMS.

MKAPVRVAVTGAAGQIGYSLLFRIAAGEMLGKDQPVILQLLEIPQAMKALEGVVMELEDCAFPLLAGLEATDDPKVAFKD
ADYALLVGAAPRKAGMERRDLLQVNGKIFTEQGRALAEVAKKDVKVLVVGNPANTNALIAYKNAPGLNPRNFTAMTRLDH
NRAKAQLAKKTGTGVDRIRRMTVWGNHSSTMFPDLFHAEVDGRPALELVDMEWYEKVFIPTVAQRGAAIIQARGASSAAS
AANAAIEHIRDWALGTPEGDWVSMAVPSQGEYGIPEGIVYSFPVTAKDGAYRVVEGLEINEFARKRMEITAQELLDEMEQ
VKALGLI