Stability analysis of the bacteriophage phiKMV lysin gp36C and its putative role during infection.
The kinetic, thermodynamic and structural stability of gp36C, the virion-associated peptidoglycan hydrolase domain of bacteriophage phiKMV, is analyzed. Recombinant gp36C is highly thermoresistant (k = 0.595 h(-1) at 95 degrees C), but not thermostable (T(m) = 50.2 degrees C, DeltaH(cal) = 6.86 x 10(4) cal mol(-1)). However, aggregation influences kinetic stability in an unusual manner since aggregation is more pronounced at 55 degrees C than at higher temperatures. Furthermore, gp36C reversibly unfolds in a two-state endothermic transition, and circular dichroism analysis shows that gp36C almost completely refolds after a 3-h heat treatment at 85 degrees C. These properties are in agreement with gp36C being part of the extensible tail which is ejected in an unfolded state during phage infection.
Briers
Y
Y
Division of Gene Technology, Katholieke Universiteit Leuven, Kasteelpark Arenberg 21, Leuven 3001, Belgium. yves.briers@biw.kuleuven.be
Lavigne
R
R
Plessers
P
P
Hertveldt
K
K
Hanssens
I
I
Engelborghs
Y
Y
Volckaert
G
G
D000595:Amino Acid Sequence; D001435:Bacteriophages / Q000472:pathogenicity*; D002152:Calorimetry, Differential Scanning; D002942:Circular Dichroism; D007700:Kinetics; D008969:Molecular Sequence Data; D011549:Pseudomonas / Q000821:virology*; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013053:Spectrophotometry; D013816:Thermodynamics; D014764:Viral Proteins / Q000737:chemistry* / Q000494:pharmacology
D014764:Viral Proteins; C513874:lysin gp36C, bacteriophage phiKMV