title: [Spectral characteristics and the structure of chloroplasts upon blocking the early stages of chlorophyll biosynthesis].
abstract: The cotton mutant xantha (Gossypium hirsutum L.) with the blocked synthesis of 5-aminolevulinic acid in the light has been shown to accumulate chlorophyll 30 times less than the parent type. In chloroplasts of the mutant xantha, the formation of the membrane system is blocked at the earliest stages, mainly at the stage of bubbles and single short thylakoids. Only light-harvesting chlorophyll-a/b-protein complexes I and II with chlorophyll fluorescence maxima at 728 and 681 nm, respectively, are formed in plastid membranes of the mutant. It has been concluded that the genetic block of chlorophyll biosynthesis in the mutant xantha disturbs the formation and functioning of the complexes in reaction centers of PS-I and PS-II, inhibiting the development of the whole membrane system of chloroplasts at the stage of bubbles and single thylakoids.
authors.forename: V G
authors.initials: VG
authors.lastname: Ladygin
mesh_terms: D002734:Chlorophyll / Q000096:biosynthesis* / Q000737:chemistry* / Q000235:genetics; D003368:Gossypium / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D009154:Mutation; D045331:Photosystem I Protein Complex / Q000737:chemistry / Q000378:metabolism; D045332:Photosystem II Protein Complex / Q000737:chemistry / Q000378:metabolism; D018515:Plant Leaves / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D013050:Spectrometry, Fluorescence; D020524:Thylakoids / Q000737:chemistry* / Q000378:metabolism / Q000648:ultrastructure
chemical_list: D045331:Photosystem I Protein Complex; D045332:Photosystem II Protein Complex; D002734:Chlorophyll