Chemical modification of amino acid residues in glycerinated Vorticella stalk and Ca(2+)-induced contractility.
The glycerinated stalk of the peritrich ciliate Vorticella, was treated with various reagents to chemically modify the amino acid residues. The influences of these modifcations on spasmoneme contractility were investigated. First, it was confirmed that the spasmoneme contraction is not inhibited by alteration of SH groups. It was also demonstrated that chemical modification of methionine and tryptophan residues abolishes spasmoneme contractility. The reagents used for chemical modification were N-bromosuccinimide (NBS), chloramine T, and 2-hydroxy-5-nitrobenzyl bromide (HNBB), which abolished spasmoneme contractility at concentrations of 40-50 microM, 200-300 microM, and 4 mM, respectively. These results suggest that, along with Ca2+ binding proteins, there are other as yet to be identified proteins involved in contractility.
Kono
R
R
Department of Physics, Waseda University, Tokyo, Japan.
Ochiai
T
T
Asai
H
H
D015077:2-Hydroxy-5-nitrobenzyl Bromide / Q000494:pharmacology; D000818:Animals; D001665:Binding Sites; D001974:Bromosuccinimide / Q000494:pharmacology; D002118:Calcium / Q000494:pharmacology*; D002135:Calcium-Binding Proteins / Q000502:physiology; D002700:Chloramines / Q000494:pharmacology; D016798:Ciliophora / Q000187:drug effects / Q000502:physiology*; D005990:Glycerol / Q000494:pharmacology; D008715:Methionine; D009068:Movement / Q000187:drug effects; D015800:Protozoan Proteins / Q000737:chemistry / Q000502:physiology*; D014105:Tosyl Compounds / Q000494:pharmacology; D014364:Tryptophan
D002135:Calcium-Binding Proteins; D002700:Chloramines; D015800:Protozoan Proteins; D014105:Tosyl Compounds; C016300:chloramine-T; D015077:2-Hydroxy-5-nitrobenzyl Bromide; D014364:Tryptophan; D008715:Methionine; D001974:Bromosuccinimide; D005990:Glycerol; D002118:Calcium