Abstract:
:We propose a reaction model for the palytoxin-sodium-potassium (PTX-Na(+)/K(+)) pump complex. The model, which is similar to the Albers-Post model for Na(+)/K(+)-ATPase, is used to elucidate the effect of PTX on Na(+)/K(+)-ATPase during the enzyme interactions with Na(+) and/or K(+) ions. Conformational substates and reactions for the pump are incorporated into the Albers-Post model to represent enzymes with or without bound PTX. A mathematical model based on the reaction scheme is used in simulations modeling experimental studies of PTX-induced ionic currents. Our simulations suggest that (i) extracellular Na(+) as well as K(+) promotes PTX-induced channel blockage; (ii) extracellular K(+) accelerates PTX unbinding; and (iii) K(+) occlusion in the PTX-pump complex is essential for describing the PTX-induced current dynamics.
journal_name
Phys Bioljournal_title
Physical biologyauthors
Rodrigues AM,Almeida AC,Infantosi AFdoi
10.1088/1478-3975/5/3/036005subject
Has Abstractpub_date
2008-07-29 00:00:00pages
036005issue
3eissn
1478-3967issn
1478-3975pii
S1478-3975(08)76796-7journal_volume
5pub_type
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