title: A method for isolating a high yield of Arabidopsis chloroplasts capable of efficient import of precursor proteins.
abstract: Chloroplasts were isolated from Arabidopsis plants grown under different conditions, and using different protocols, to determine a method that would yield chloroplasts capable of binding and importing precursor proteins. Chloroplasts isolated from protoplasts and purified on a Percoll gradient were highly import-competent, with little non-specific binding of the precursor, and a high yield of intact chloroplasts (0.1 mg chlorophyll/g FW). Chloroplasts from plants grown on agar plates had a much higher rate of import than those from plants grown on soil. Protein import remained high at all of the ages tested for chloroplasts from plate-grown plants, whereas it declined during the development of soil-grown plants. Arabidopsis chloroplasts imported a range of precursor proteins and had nucleotide requirements for binding and import similar to those reported for pea chloroplasts.
authors.affiliation: MSU-Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI 48824-1312, USA.
authors.forename: L M
authors.initials: LM
authors.lastname: Fitzpatrick
authors.forename: K
authors.initials: K
authors.lastname: Keegstra
mesh_terms: D017360:Arabidopsis / Q000254:growth & development / Q000378:metabolism / Q000648:ultrastructure*; D002736:Chloroplasts / Q000378:metabolism / Q000502:physiology*; D010450:Endopeptidases / Q000494:pharmacology; D009711:Nucleotides / Q000378:metabolism; D021381:Protein Transport / Q000502:physiology*
chemical_list: D009711:Nucleotides; D010450:Endopeptidases