ISSN:
0886-1544
Keywords:
motility
;
Ca2+
;
ionophores
;
spirulina subsalsa
;
Life and Medical Sciences
;
Cell & Developmental Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Medicine
Notes:
Motility of the marine filamentous cyanobacterium Spirulina subsalsa is both Ca2+ and Na+ dependent, and replacement of Na+ by mannitol arrests it. The data presented suggest that Ca2+ interacts with sites on the surface of the cell membrane. The inhibitory effect of dicyclohexylcarbodiimide (DCCD) hints at the possibility that the role of Ca2+ may be associated with a membrane bound Ca-ATPase. Motility is pH dependent, being nil at pH 〈 6.5 and 〉 10.0, with an optimum at 8.5. Norepinephrine abolishes most of the inhibitory effect of low pH on motility. Ca2+ has an “all-or-none” effect on motility that is triggered at 5 mM. Acetylcholine lowers the threshold of Ca2+ necessary for triggering motility.
Additional Material:
11 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cm.970020408
Permalink
