Folding of a synthetic parallel beta-roll protein.
Recently, the design of beta-sheet proteins and concomitant folding studies have attracted increasing attention. A unique natural all-beta domain occurs in a family of cytolytic bacterial toxins, the so-called RTX toxins. This domain consists of a variable number (about 6-45) of tandem repeats of a glycine-rich nine-residue motif with the consensus sequence GGXGXDX(L/I/F)X. The analysis of the three-dimensional structure of alkaline protease from Pseudomonas aeruginosa which possesses six of these repeats revealed that they fold into a novel 'parallel beta-roll' where calcium is bound within the turns connecting the beta-strands. A 75-mer peptide of the sequence NH(2)-WLS-[GGSGNDNLS](8)-COOH was chemically synthesised. Circular dichroism spectroscopy showed that this polypeptide folds in the presence of Ca(2+) and polyethylene glycol into a beta-structure which is presumably identical with the parallel beta-roll. This synthetic beta-roll behaves similarly to the isolated beta-roll domains from Escherichia coli haemolysin or Bordetella pertussis cyclolysin in terms of calcium binding and polymerisation behaviour.
Lilie
H
H
Institut für Biotechnologie der Martin-Luther-Universität Halle, Kurt-Mothes Strasse 3, D-06120, Halle/Saale, Germany. lilie@biochemtech.uni-halle.de
Haehnel
W
W
Rudolph
R
R
Baumann
U
U
D037361:Adenylate Cyclase Toxin; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism; D001427:Bacterial Toxins / Q000138:chemical synthesis / Q000737:chemistry* / Q000378:metabolism*; D001704:Biopolymers / Q000737:chemistry / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D002942:Circular Dichroism; D016384:Consensus Sequence; D029968:Escherichia coli Proteins; D005998:Glycine / Q000378:metabolism; D006460:Hemolysin Proteins / Q000737:chemistry / Q000378:metabolism; D007700:Kinetics; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000138:chemical synthesis / Q000737:chemistry* / Q000378:metabolism*; D011092:Polyethylene Glycols / Q000378:metabolism; D017510:Protein Folding; D011498:Protein Precursors / Q000737:chemistry / Q000378:metabolism; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D020449:Repetitive Sequences, Amino Acid; D012697:Serine Endopeptidases / Q000737:chemistry / Q000378:metabolism; D012995:Solubility
D037361:Adenylate Cyclase Toxin; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D001704:Biopolymers; D029968:Escherichia coli Proteins; D006460:Hemolysin Proteins; C036507:Hlya protein, E coli; D010446:Peptide Fragments; D011498:Protein Precursors; D011092:Polyethylene Glycols; C038495:Pseudomonas serine proteinase; D012697:Serine Endopeptidases; D002118:Calcium; D005998:Glycine