Ammonia and the induction of microcyst differentiation in wild-type and mutant strains of the cellular slime mold Polysphondylium pallidum☆
[摘要] Althoughlowlevels(0.16μmole107cells,ml)ofammoniaarepresentinvegetative,germinating,andyoungencystmentculturesofwild-type(WS-320)cells,a12-foldincreaseinextracellularammoniaoccursduringmicrocystdifferentiationinthecellularslimemoldPolysphondyliumpallidum.WhenWS-320amoebaewereplacedinconditionedmediumfromotherwild-typeencystmentcultures,microcystformationwasinitiatedearlierthanincontrol(120mMKCl)cultures.IsoosmoticsolutionscontainingNH4ClandKClalsocausedWS-320cellstoencystearlier.Similarresultswereobtainedwithmutantstrains.In120mMKCl,strainsmic-1andmic-2produce21and64%microcysts,respectively,whilestrainsPN582andPN651donotencyst.Themutantmic-1secreteswild-typelevelsofammonia,whilemic-2,PN582,andPN651allsecretemuchloweramounts.ConditionedmediumandsolutionscontainingNH4ClandKClincreasedtherateofdevelopmentandthenumberofmicrocystsproducedbymic-2andinducedmicrocystdevelopmentinthecystlessmutantPN582.Takentogetherthesedataindicatethatammoniaactsasaninducerofmicrocystdifferentiation.
[发布日期] [发布机构]
[效力级别] [学科分类] 生物科学（综合）
[关键词] [时效性]
