Localization of the mechanism of pH-dependent non- photochemical fluorescence quenching in thylakoid membranes

Higher plants have evolved a well-conserved set of photoprotective mechanisms, collectively designated Non-Photochemical Quenching of chlorophyll fluorescence (qN), to deal with the inhibitory absorption of excess light energy by the photosystems. Their main contribution originates from safe thermal deactivation of excited states promoted by a highly-energized thylakoid membrane, detected via lumen acidification. The precise origins of this energy- or LlpH-dependent quenching (qE), arising from either decreased energy transfer efficiency in PSII antennae (~ Young & Frank, 1996; Gilmore & Yamamoto, 1992; Ruban et aI., 1992), from alternative electron transfer pathways in PSII reaction centres (~ Schreiber & Neubauer, 1990; Thompson &Brudvig, 1988; Klimov et aI., 1977), or from both (Wagner et aI., 1996; Walters & Horton, 1993), are a source of considerable controversy. In this study, the origins of qE were investigated in spinach thylakoids using a combination of fluorescence spectroscopic techniques: Pulse Amplitude Modulated (PAM) fluorimetry, pump-probe fluorimetry for the measurement of PSII absorption crosssections, and picosecond fluorescence decay curves fit to a kinetic model for PSII. Quenching by qE (,..,600/0 of maximal fluorescence, Fm) was light-induced in circulating samples and the resulting pH gradient maintained during a dark delay by the lumenacidifying capabilities of thylakoid membrane H+ ATPases. Results for qE were compared to those for the addition of a known antenna quencher, 5-hydroxy-1,4naphthoquinone (5-0H-NQ), titrated to achieve the same degree of Fm quenching as for qE. Quenching of the minimal fluorescence yield, F0' was clear (8 to 130/0) during formation of qE, indicative of classical antenna quenching (Butler, 1984), although the degree was significantly less than that achieved by addition of 5-0H-NQ. Although qE induction resulted in an overall increase in absorption cross-section, unlike the decrease expected for antenna quenchers like the quinone, a larger increase in crosssection was observed when qE induction was attempted in thylakoids with collapsed pH gradients (uncoupled by nigericin), in the absence of xanthophyll cycle operation (inhibited by DTT), or in the absence of quenching (LlpH not maintained in the dark due to omission of ATP). Fluorescence decay curves exhibited a similar disparity between qE-quenched and 5-0H-NQ-quenched thylakoids, although both sets showed accelerated kinetics in the fastest decay components at both F0 and Fm. In addition, the kinetics of dark-adapted thylakoids were nearly identical to those in qEquenched samples at F0' both accelerated in comparison with thylakoids in which the redox poise of the Oxygen-Evolving Complex was randomized by exposure to low levels of background light (which allowed appropriate comparison with F0 yields from quenched samples). When modelled with the Reversible Radical Pair model for PSII (Schatz et aI., 1988), quinone quenching could be sufficiently described by increasing only the rate constant for decay in the antenna (as in Vasil'ev et aI., 1998), whereas modelling of data from qE-quenched thylakoids required changes in both the antenna rate constant and in rate constants for the reaction centre. The clear differences between qE and 5-0H-NQ quenching demonstrated that qE could not have its origins in the antenna alone, but is rather accompanied by reaction centre quenching. Defined mechanisms of reaction centre quenching are discussed, also in relation to the observed post-quenching depression in Fm associated with photoinhibition.

Charles C. Chapman and Ethel Chapman Wickett at a birthday picnic for Charles C. Chapman at Orange County Park, California, July 2, 1937

Charles C. Chapman and Ethel Chapman Wickett at a birthday picnic for Charles C. Chapman at Orange County Park, California, July 2, 1937. [Copy an excerpt of CCCF27]

Charles C. Chapman, Ethel Chapman Wickett and Stanley Chapman at Orange County Park, 1937

Charles C. Chapman, Ethel Chapman Wickett and Stanley Chapman at birthday picnic for Charles C. Chapman at Orange County Park, California, July 2, 1937.

John W. Fisher Fonds, 1937-1961, 1964-1989, 1993, n.d.

Norah and Fred Fisher welcomed John Fisher into the world on November 29, 1912, not knowing what an influential role he would play in shaping Canada's history. John Fisher grew up as the middle child of five brothers and sisters in Frosty Hollow, New Brunswick, close to today’s town of Sackville. Sackville’s main industry was the Enterprise Foundry which the Fisher family owned and operated; however, Fisher had no plans of going into the family business. He was more inspired by his maternal grandfather, Dr. Cecil Wiggins, who lived with the family after retiring from the Anglican ministry. Wiggins encouraged all his grandchildren to be well read and to take part in discussions on current events. There were often visitors in the Fisher household taking part in discussions about politics, religion, and daily life. Fisher forced himself to take part in these conversations to help overcome his shyness in social settings. These conversations did help with his shyness and also in forming many opinions and observations about Canada. It put Fisher on the road to becoming Mr. Canada and delivering the many eloquent speeches for which he was known. Fisher did not venture far from home to complete his first degree. In 1934 he graduated from Mount Allison University in Sackville, NB with an Arts degree. The same year Fisher enrolled in Dalhousie’s law school. During his time at Dalhousie, Fisher discovered radio through Hugh Mills. Mills or “Uncle Mel” was on CHNS, Halifax’s only radio station at the time. Fisher began by making appearences on the radio drama show. By 1941 he had begun writing and broadcasting his own works and joined the staff as an announcer and continuity writer. In 1936 the Canadian Broadcasting Corporation was formed, the first National radio station. Fisher joined the CBC shortly after it’s beginning and remained with them, as well as the Halifax Herald newspaper, even after his law school graduation in 1937. By 1943 Fisher’s talks became a part of the CBC’s programming for a group of maritime radio stations. Fisher once described his talks as follows “my talks weren’t meant to be objective. . . they were meant to be favourable. They were ‘pride builders’” He began his famed John Fisher Reports at CBC Toronto when he transfered there shortly after the war. This program brought emmence pride to the fellow Canadians he spoke about leading to approximately 3500 requests per year to speak at banquets and meeting throughout Canada and the United States. Fisher was a well travelled indivdual who would draw on personal experiences to connect with his audience. His stories were told in simple, straight forward language for anyone to enjoy. He became a smooth, dynamic and passionate speaker who sold Canada to Canadians. He became a renowned journalist, folk historian, writer and broadcaster. Fisher was able to reach a vast array of people through his radio work and build Canadian pride, but he did not stop there. Other ways Fisher has contributed to Canada and the Canadian people include: Honoured by five Canadian Universities. 1956, became the Director of the Canadian Tourist Association. 1961, was appointed Special Assistant to the Prime Minister of Canada. 1963, Commissioner of the Centennial Commission (the Federal Agency Responsible for Canada’s 100th birthday) 1968, received the Service Medal , a coveted Order of Canada. President of John Fisher Enterprises Ltd., private consultant work, specializing in Centennial planning, broadcasts, lectures and promotion. John Fisher continued recording radio broadcasts even after his diagnosis with cancer. He would record 3 or 4 at a time so he was free to travel across Canada, the U.S., Europe and Mexico in search of treatments. Fisher passed away from the disease on February 15, 1981 and he is buried at Mount Pleasant Cemetery in Toronto.

Kevin McCabe Collection, 1966-1979, 1981, 1991-1996,

Kevin McCabe received his PhD in Roman Studies from McMaster University. He has taught at The University of Regina, Nipissing University and Brock University. He was the editor of Gracefully Speaking: newsletter of the Grace Mennonite Church and The Poetry of Old Niagara. He is also the co- editor of The Poetry of Lucy Maud Montgomery and The Lucy Maud Montgomery Album.

Proceedings : Grand Lodge, A.F. & A.M. of Canada in the Province of Ontario - 1937

On spine : The Grand Lodge of Canada in the Province of Ontario.

Proceedings : Grand Lodge, A.F. & A.M. of Canada in the Province of Ontario - 1996

On spine : The Grand Lodge of Canada in the Province of Ontario.

Niagara South estate and legal documents collection, 1752-1937, n.d. [non-inclusive]

The documents in the collection include the names of families residing in Stamford Township, Welland County, which today is considered Niagara Falls. Some names are: Allan, Barnett, Brokenshaw, Buchanan, Cadham, Clark, Dalton, Dell, Fell, Garner, Hemmings, Kent, Lightbody, Orchard, Perry, Pew, Ross, Street, Thompson, Willox, Willson, Wright. For a more complete list of names consult the finding aid.

Commemorative stamps, British, American and Canadian, 1974-1977, 1982-1984, 1996.

The Guernsey post office stamps consist of 2 exhibition series souvenir sheets commemorating Major-General Sir Issac Brock, 1769-1812. The stamp was issued in 1996 to celebrate Guernsey’s attendance at Canada’s international stamp exhibition CAPEX 96. The stamps issued by the United States postal service consist of 1 sheet of stamps commemorating the 50th anniversary of the Peace Bridge, 1927-1977. The stamps issued by Canada Post include 5 commemorative day-of-issue envelopes with stamps featuring William Hamilton Merritt and the Welland Canal. This stamp was issued in 1974 to celebrate the 150th anniversary of the canal. There is also a set of 4 inscription corner blocks of stamps. These items are contained in an envelope addressed to Mr. J.N. Jackson, St. Catharines, ON. There is also a separate sheet of the same stamp. Also issued by Canada Post are 2 full sheets of stamps, one commemorating the 50th anniversary of the Peace Bridge (1927-1977), and one commemorating 25 years of the St. Lawrence Seaway (1959-1984). Lastly, there are 2 full sheets of stamps commemorating the 100th anniversary of the Royal Henley Regatta, issued in 1982.

Local Postcards, 1996, n.d.

6 of the postcards are sketches by Norbert Collins, these include: St. George’s Anglican Church, the museum, St. Paul United Church, Ridley College clock tower, St. Catherine’s Cathedral and the Willam Hamilton Merritt monument (all of St. Catharines). The 7th postcard is a picture of the St. Catharines Craft Guild Shop in Port Dalhousie (artist unknown). Norbert J. Collins is a Canadian artist.

Warren Hartman fonds, 1970, 1972-1996, 1998, n.d.

Warren Hartman was born in 1942 in Toronto, Ontario. He received a B.A. in Fine Arts and Drama from Brock University in 1981 and a Masters of Arts in Humanities at the State University of New York at Buffalo in 1987. In the 1950s he did considerable work as a child-actor both in theatre and television. From 1953 to 1961 he was in the New Play Society under the direction of Dora Mavor Moore. His last two years there were spent as a scholarship student. From 1963 to 1966 he did an apprenticeship with Suzanne Mess, Head of Costume Design at The Canadian Opera Company in Toronto. In 1976 Warren attended a Master Class in Scenography at the Banff School of Fine Arts with Josef Svoboda. In the spring of 1970 Warren was a guest designer at Brock University and from 1970 to 1972 he remained at Brock as resident designer and special lecturer. During this time he was also an instructor and costume designer at Sheridan College in Oakville. It was in 1972 that he became the designer-in-residence at Brock University. From 1984 he held the position of Associate Professor at The Department of Fine Arts at Brock University until the fall of 1996. Some of the highlights of Warren’s career also include: stage managager with the Street Hat Players in Port Carling, Ontario, 1960-1961; a freelance designer for over 100 shows; costume coordinator(production manager) for the Canadian Opera Company, 1964 -1970; resident costume designer for The Canadian Opera Company, 1965- 1970; founder and artistic director of Dei Gelosi Campagnia, St.Catharines, Ontario, 1970-1973; freelance director of some thirty-five shows; co-producer for Quebec City Summer Stock Company, Quebec City, Quebec, 1975; a consultant with Alberta Culture for the Provincial Government of Alberta, 1986-1987 and associate artistic director at Theatre Network, Edmonton, Alberta, 1986-1987. Warren Hartman was the recipient of the Jean Chalmers Award for contributions to Canadian Theatre for persons 25 years of age or under, in 1965. He was a founding member of Associated Designers of Canada and was affiliated with Canadian Actors Equity. Warren Hartman died on Feb. 11, 1998 several days after suffering a massive stroke. A memorial service was held at Brock University in May of 1998 and a bursary fund was established in his name.

Report of Loss in Capacity Due to Ice at Rankine Station - April 1934 through April 1937

A report compiled by Canadian Niagara Power Company describes the loss in capacity due to ice. The chart reveals the kilowatts lost and the duration of the outage and the "min. forebay elevation during ice loss period".

Proceedings of the Grand Chapter of Royal Arch Masons of Canada at the annual convocation, 1937

Annual Convocation proceedings for the year 1937. The title varies slightly and convocation held at different cities or towns in Canada. Seventy-ninth annual convocation.

Annual convocation 1996 Proceedings (1996)

Annual Convocation proceedings for the year 1996. The title varies slightly and convocation is held at different cities or towns in Canada. One hundred and thirty-eighth annual convocation.

Niagara churches collection, 1937, 1968-1994

This collection contains 7 church programs and brochures, ranging in date from 1937 to 1994. There are programs for church services at Knox Presbyterian Church, St. Catharines (May 9, 1937); St. Catherine of Alexandria Cathedral, St. Catharines (July 28, 1968) ; Memorial United Church, Ridgeway (October 15, 1972); Salem Chapel, British Methodist Episcopal Church, St. Catharines (November 30, 1986); and Ridley College Memorial Chapel, St. Catharines (December 3 & 4, 1994). There is also a brochure of activities offered at St. Paul Street United Church, St. Catharines (1986), and a development fund appeal brochure for the Cathedral of St. Catherine, St. Catharines (1985).