EXTRACTION, ASSAY AND SOME PROPERTIES OF FLORIDOSIDE PHOSPHATE SYNTHASE FROM <i>PORPHYRA PERFORATA</i> (RHODOPHYTA)<sup>1</sup>

Journal of Phycology - Tập 26 Số 4 - Trang 683-688 - 1990
Jianxin Meng1, Lalit M. Srivastava1
1Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6

Tóm tắt

ABSTRACTA suitable method for extraction of floridoside phosphate synthase (FPS, UDP‐galactose: sn‐3‐glycerol phosphate: 1→2′α‐D‐galactosyl transferase)from Porphyra perforata J. Ag. was developed. Two assay methods for enzyme activity were utilized, one measuring the amount of floridoside formed by using gas‐liquid chromatography, the other measuring the sn‐3‐glycerol phosphate‐dependent formation of UDP; both assays gave similar results. FPS is a soluble protein, and FPS activity in the extract as determined by the amount of product formed in vitro compared well with the in vivo rate of floridoside synthesis (4–7 μMmol product formed·h−1·g−1 fresh wt). The rate of product formation in vitro was linear up to 45 min and proportional to protein concentration in the assay mixture. The temperature optimum was 30–35° C. FPS was active over a range of pH values from 7.0–8.5. It was stable in concentrated solutions in the presence of 0.3 M ammonium sulfate, but activity was lost in diluted solution (protein concentration below 0.2 mg·mL−1) or below 0.2 M ion strength. The data suggest that FPS may be an oligomeric protein which occurs free in the cytoplasm or loosely bound to a membrane. It may also be a regulatory protein controlling the overall rate of synthesis of floridoside in vivo.

Từ khóa


Tài liệu tham khảo

10.1016/S0031-9422(00)86327-X

Bran B. C., 1955, Assimilation of 14CO2 by a photosynthesizing red alga, Iridophycus flaccidum, J. Biol. Chem., 212, 411, 10.1016/S0021-9258(18)71129-0

10.1139/b58-029

10.1016/0003-2697(76)90527-3

10.1111/j.1399-3054.1987.tb02855.x

10.1139/b68-088

Goodwin T. W., 1983, Introduction to Plant Biochemistry, 249

Kochert G., 1978, Handbook of Phycological Methods Physiological and Biochemical Methods, 95

10.1016/0304-4211(81)90047-X

10.1021/jo01258a003

10.1016/0076-6879(74)31057-9

10.1104/pp.82.1.136

10.1139/b66-066

Marsden W. J. N., 1981, A novel and comprehensive approach to the extraction of enzymes from brown algae, and their separation by polyacrylamide gel electrophoresis, Mar. Biol. Lett., 2, 353

Meeuse B. J. D., 1962, Physiology and Biochemistry of Algae, 289

10.1016/S0008-6215(00)90075-2

Meng J.&Srivastava L. M.1990.Partial purification and characterization of floridoside phosphate synthase from Porphyra perforata.Phytochemistry. In press.

10.1111/j.1432-1033.1983.tb07516.x

10.15281/jplantres1887.82.462

10.1111/j.1432-1033.1984.tb08293.x

10.1111/j.1432-1033.1975.tb02205.x

Ragan M. A., 1978, Handbook of Phycological Methods Physiological and Biochemical Methods, 157

10.1093/jxb/31.6.1539

10.2216/i0031-8884-26-2-235.1

10.1016/0014-5793(78)80576-6

10.1104/pp.76.4.910

10.1007/BF00394774

10.1111/j.1432-1033.1984.tb08222.x

10.1016/S0044-328X(81)80157-2

Thông tin
Thông tin xuất bản

Journal of Phycology

Tập 26 Số 4

683-688

Thông tin tác giả