Joan Mary Anderson 1932–2015

Joan Mary (Jan) Anderson pioneered the investigation of the molecular organisation of the plant thylakoid membrane, making seminal discoveries that laid the foundations for the current understanding of photosynthesis. She grew up in Queenstown, New Zealand, obtaining a BSc and MSc at the University of Otago in Dunedin. After completing her PhD at the University of California, she embarked on a glittering career at the Commonwealth Scientific and Industrial Research Organisation (CSIRO) and then Australian National University (ANU) in Canberra. Not only a gifted experimentalist, Jan was a creative thinker, not afraid to put her insightful and prophetic hypotheses into the public domain. Her many notable achievements include establishing the details and the physiological significance of lateral heterogeneity in the distribution of the two photosystems between stacked and unstacked thylakoid membranes and the dynamic changes in the extent of stacking that occur in response to changes in the light environment. Her investigations brought her into collaboration with prominent researchers throughout the world. Recognised with many honours as a leading scientist in Australia, international recognition included Lifetime Achievement Award from the International Society of Photosynthesis Research, and Honorary Fellowships at Universities in the UK and USA.

Joan Mary Anderson. 12 May 1932—28 August 2015

Joan Mary (Jan) Anderson pioneered the investigation of the molecular organization of the plant thylakoid membrane, making seminal discoveries that laid the foundations for the current understanding of photosynthesis. She grew up in Queenstown, New Zealand, obtaining a BSc and MSc at the University of Otago in Dunedin. After completing her PhD at the University of California, she embarked on a glittering career at CSIRO and then the Australian National University in Canberra. Not only a gifted experimentalist, Jan was a creative thinker, not afraid to put her insightful and prophetic hypotheses into the public domain. Her many notable achievements include establishing the details and the physiological significance of lateral heterogeneity in the distribution of the two photosystems between stacked and unstacked thylakoid membranes and the dynamic changes in the extent of stacking that occur in response to changes in the light environment. Her investigations brought her into collaboration with leading researchers throughout the world. Recognized with many honours as a leading scientist in Australia, international recognition included the Lifetime Achievement Award from the International Society of Photosynthesis Research and honorary fellowships at universities in the UK and USA.

Optimization of light harvesting and photoprotection: molecular mechanisms and physiological consequences

The distinctive lateral organization of the protein complexes in the thylakoid membrane investigated by Jan Anderson and co-workers is dependent on the balance of various attractive and repulsive forces. Modulation of these forces allows critical physiological regulation of photosynthesis that provides efficient light-harvesting in limiting light but dissipation of excess potentially damaging radiation in saturating light. The light-harvesting complexes (LHCII) are central to this regulation, which is achieved by phosphorylation of stromal residues, protonation on the lumen surface and de-epoxidation of bound violaxanthin. The functional flexibility of LHCII derives from a remarkable pigment composition and configuration that not only allow efficient absorption of light and efficient energy transfer either to photosystem II or photosystem I core complexes, but through subtle configurational changes can also exhibit highly efficient dissipative reactions involving chlorophyll–xanthophyll and/or chlorophyll–chlorophyll interactions. These changes in function are determined at a macroscopic level by alterations in protein–protein interactions in the thylakoid membrane. The capacity and dynamics of this regulation are tuned to different physiological scenarios by the exact protein and pigment content of the light-harvesting system. Here, the molecular mechanisms involved will be reviewed, and the optimization of the light-harvesting system in different environmental conditions described.

Characterization of PSII–LHCII supercomplexes isolated from pea thylakoid membrane by one-step treatment with α- and β-dodecyl- d -maltoside

It was the work of Jan Anderson, together with Keith Boardman, that showed it was possible to physically separate photosystem I (PSI) from photosystem II (PSII), and it was Jan Anderson who realized the importance of this work in terms of the fluid-mosaic model as applied to the thylakoid membrane. Since then, there has been a steady progress in the development of biochemical procedures to isolate PSII and PSI both for physical and structural studies. Dodecylmaltoside (DM) has emerged as an effective mild detergent for this purpose. DM is a glucoside-based surfactant with a bulky hydrophilic head group composed of two sugar rings and a non-charged alkyl glycoside chain. Two isomers of this molecule exist, differing only in the configuration of the alkyl chain around the anomeric centre of the carbohydrate head group, axial in α-DM and equatorial in β-DM. We have compared the use of α-DM and β-DM for the isolation of supramolecular complexes of PSII by a single-step solubilization of stacked thylakoid membranes isolated from peas. As a result, we have optimized conditions to obtain homogeneous preparations of the C 2 S 2 M 2 and C 2 S 2 supercomplexes following the nomenclature of Dekker & Boekema (2005 Biochim. Biophys. Acta 1706 , 12–39). These PSII–LHCII supercomplexes were subjected to biochemical and structural analyses.

"Yuh Mad Man!" Lying Letters: Speculations on the Catalysts of Male Madness in Caribbean Literature

Jan Anderson is invested in tracing the Trajectory Home (a working title for a collection of essays) among the African Diaspora, particularly those of Caribbean descent. The experiences and contestations over issues of belonging, citizenship, and nation building are also at the heart of Jan’s work. Jan’s submission has led to a focus on the recurrence of disenfranchisement as a legacy of “diaspora” and the resulting fissures in male/female relationships.