caa a22 4500 477100007 CHVBK 20180405111538.0 cr unu---uuuuu 170330e19960901xx s 000 0 eng 10.1007/BF00196645 doi (NATIONALLICENCE)springer-10.1007/BF00196645 The CO2-concentrating mechanism in a starchless mutant of the green unicellular alga Chlorella pyrenoidosa [Elektronische Daten] [María del Pino Plumed, Arsenio Villarejo, Asunción de los Róos, Guillermo García-Reina, Ziyadin Ramazanov] The CO2-concentrating mechanism (CCM) was induced in the green unicellular alga Chlorella when cells were transferred from high (5% CO2) to low (0.03%) CO2 concentrations. The induction of the CCM correlated with the formation of a starch sheath specifically around the pyrenoid in the chloroplast. With the aim of clarifying whether the starch sheath was involved in the operation of the CCM, we isolated and physiologically characterized a starchless mutant of Chlorella pyrenoidosa, designated as IAA-36. The mutant strain grew as vigorously as the wild type under high and low CO2 concentrations, continuous light and a 12 h light/12 h dark photoperiod. The CO2 requirement for half-maximal rates of photosynthesis [K0.5(CO2)] decreased from 40 μM to 2-3 μM of CO2 when both wild type and mutant were switched from high to low CO2. The high affinity for inorganic carbon indicates that the IAA-36 mutant is able to induce a fully active CCM. Since the mutant does not have the pyrenoid starch sheath, we conclude that the sheath is not involved in the operation of the CCM in Chlorella cells. Springer-Verlag, 1996 Chlorella nationallicence CO2 nationallicence concentrating mechanism nationallicence Photosynthesis nationallicence Pyrenoid nationallicence Starch nationallicence CCM : CO2 concentrating mechanism nationallicence high nationallicence CO2 : air supplemented with 5% CO2 (v/v) nationallicence low CO2 : air containing ambient 0.03% CO2 (v/v) nationallicence WT : wild type nationallicence del Pino Plumed María Institute de Algologia Aplicada, Institute Tecnológico de Canarias/ULPGC, Muelle de Taliarte s/n, E-35214-Telde, Las Palmas, Spain aut Villarejo Arsenio Institute de Algologia Aplicada, Institute Tecnológico de Canarias/ULPGC, Muelle de Taliarte s/n, E-35214-Telde, Las Palmas, Spain aut de los Róos Asunción Centre de Ciencias Medioambientales (CSIC), Serrano 115 bis., E-28006, Madrid, Spain aut García-Reina Guillermo Institute de Algologia Aplicada, Institute Tecnológico de Canarias/ULPGC, Muelle de Taliarte s/n, E-35214-Telde, Las Palmas, Spain aut Ramazanov Ziyadin Institute de Algologia Aplicada, Institute Tecnológico de Canarias/ULPGC, Muelle de Taliarte s/n, E-35214-Telde, Las Palmas, Spain aut Planta Springer-Verlag 200/1(1996-09-01), 28-31 0032-0935 200:1<28 1996 200 425 https://doi.org/10.1007/BF00196645 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00196645 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- del Pino Plumed María Institute de Algologia Aplicada, Institute Tecnológico de Canarias/ULPGC, Muelle de Taliarte s/n, E-35214-Telde, Las Palmas, Spain aut NATIONALLICENCE 700 1- Villarejo Arsenio Institute de Algologia Aplicada, Institute Tecnológico de Canarias/ULPGC, Muelle de Taliarte s/n, E-35214-Telde, Las Palmas, Spain aut NATIONALLICENCE 700 1- de los Róos Asunción Centre de Ciencias Medioambientales (CSIC), Serrano 115 bis., E-28006, Madrid, Spain aut NATIONALLICENCE 700 1- García-Reina Guillermo Institute de Algologia Aplicada, Institute Tecnológico de Canarias/ULPGC, Muelle de Taliarte s/n, E-35214-Telde, Las Palmas, Spain aut NATIONALLICENCE 700 1- Ramazanov Ziyadin Institute de Algologia Aplicada, Institute Tecnológico de Canarias/ULPGC, Muelle de Taliarte s/n, E-35214-Telde, Las Palmas, Spain aut NATIONALLICENCE 773 0- Planta Springer-Verlag 200/1(1996-09-01), 28-31 0032-0935 200:1<28 1996 200 425 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer