Summary
The two main proteins from the phloem exudate of Cucurbita maxima Duchesne have been isolated by ammonium-sulfate precipitation, DEAE-cellulose chromatography, and gel filtration, and have been characterized. They comprise about 40% each of the total protein. The amino-acid composition of these two proteins has been determined. Both are highly basic with an IEP above 9.5. The smaller protein has a molecular weight of ca. 30000 as determined by analytical ultracentrifugation, gel filtration, and SDS polyacrylamide gel electrophoresis. It easily dimerizes to a form which appears to be the naturally occurring structure. The larger protein has a molecular weight of 116000 (ultracentrifugation, SDS polyacrylamide gel electrophoresis). This protein forms a gel in the absence of SH-protecting agents. Several minor proteins have been detected by polyacrylamide gel electrophoresis.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Becker, D., Kluge, M., Ziegler, H.: Der Einbau von 32PO4 3− in organische Verbindungen durch Siebröhrensaft. Planta (Berl.) 99, 154–162 (1971)
Behnke, H. D., Dörr, I.: Zur Herkunft und Struktur der Plasmafilamente in Assimilatleitbahnen. Planta (Berl.) 74, 18–44 (1967)
Bieleski, R. L.: Phosphorus compounds in translocating phloem. Plant Physiol. 44, 497–502 (1969)
Bryan, J., Wilson, L.: Are cytoplasmic microtubules heteropolymers? Proc. nat. Acad. Sci. (Wash.) 68, 1762–1766 (1971)
Cronshaw, J., Esau, K.: Tubular and fibrillar components of mature and differentiating sieve elements. J. Cell Biol. 34, 801–815 (1967)
Cronshaw, J., Esau, K.: Protein in the phloem of Cucurbita I. The development of protein bodies. J. Cell Biol. 38, 25–39 (1968a).
Cronshaw, J., Esau, K.: P protein in the phloem of Cucurbita II. The P protein of mature sieve elements. J. Cell Biol. 38, 292–303 (1968b)
Eibl, H., Lands, W. E. M.: A new, sensitive determination of phosphate. Analyt. Biochem. 30, 51–57 (1969)
Edelhoch, H.: Spectroscopic determination of tryptophan and tyrosin in proteins. Biochemistry 6, 1948–1954 (1967)
Elias, H. G.: Ultrazentrifugen-Methoden. Munich: Beckman Instruments 1969
Eschrich, W., Evert, R. F., Heyser, W.: Proteins of the sieve tube exudate of Cucurbita maxima. Planta (Berl.) 100, 208–221 (1971)
Feit, H., Slusarek, L., Shelanski, M. L.: Heterogeneity of tubulin subunits. Proc. nat. Acad. Sci. (Wash.) 68, 2028–2031 (1971)
Fine, R. E.: Heterogeneity of tubulin. Nature (Lond.) New Biol. 233, 283–284 (1971)
Gardner, D. C. J., Peel, A. J.: ATP in sieve tube sap from willow. Nature (Lond.) 222, 747 (1969)
Gilder, J., Cronshaw, J.: ATPase in the phloem of Cucurbita. Planta (Berl.) 110, 189–204 (1973)
Gilder, J., Cronshaw, J.: A biochemical and cytochemical study of ATPase activity in the phloem of Nicotiana tabacum. J. Cell Biol. 60, 221–235 (1974)
Hart, J. W., Sabnis, D. D.: Colchicine-binding protein from phloem and xylem of a higher plant. Planta (Berl.) 109, 147–152 (1973)
Kleinig, H., Dörr, I., Weber, C., Kollmann, R.: Filamentous proteins from plant sieve tubes. Nature (Lond.) New Biol. 229, 152–153 (1971a)
Kleinig, H., Dörr, I., Kollmann, R.: Vinblastine-induced precipitation of phloem proteins in vitro. Protoplasma (Wien) 73, 293–302 (1971b)
Kluge, M., Becker, D., Ziegler, H.: Untersuchungen über ATP und andere organische Phosphorverbindungen im Siebröhrensaft von Yucca flaccida und Salix triandra. Planta (Berl.) 91, 68–79 (1970)
Kollmann, R., Dörr, I., Kleinig, H.: Protein filaments—structural components of the phloem exudate. I. Observations with Cucurbita and Nicotiana. Planta (Berl.) 95, 86–94 (1970)
Lehmann, J.: Zur Lokalisation von Dehydrogenasen des Energiestoffwechsels im phloem von Cucurbita pepo L. Planta (Berl.) 111, 187–198 (1973a)
Lehmann, J.: Untersuchungen am Phloemexudat von Cucurbita pepo L. I. Enzymaktivitäten von Glykolyse, Gärung und Citrat-Zyklus. Planta (Berl.) 114, 41–51 (1973b)
Lehmann, J.: Untersuchungen am Phloemexudat von Cucurbita pepo L. II. Enzymaktivitäten der Gluconeogenese und des Auf- und Abbaus von Di- und Polysacchariden. Planta (Berl.) 114, 51–61 (1973c)
Lowry, D. H., Rosebrough, N. J., Farr, N. L., Randall, R. L.: Protein measurement with the Folin phenol reagent. J. biol. Chem. 193, 265–275 (1951)
Parthasarathy, M. V., Mühlethaler, K.: Ultrastructure of protein tubules in differentiating sieve elements. Cytobiol. 1, 17–36 (1969)
Pollard, T. D., Korn, E. D.: Acanthamoeba myosin. I. Isolation from Acanthamoeba castellanii of an enzyme similar to muscle myosin. J. biol. Chem. 248, 4682–8690 (1973)
Shapiro, A. L., Vinuela, E., Maizel, J. V.: Molecular-weight estimation of polypeptide chains by electrophoresis in SDS-polyacrylamide gels. Biochim. biophys. Res. Commun. 28, 815–820 (1967)
Spencer, R. L., Wold, F.: A new convenient method for estimation of total cysteinecystine in proteins. Analyt. Biochem. 32, 185–190 (1969)
Tuppy, H., Wiesbauer, T., Wintersberger, E.: Aminosäure-p-nitroanilide als Substrate für Aminopeptidasen und andere proteolytische Fermente. Hoppe-Seylers Z. physiol. Chem. 329, 278–288 (1962)
Walker, T. S.: The purification and some properties of a protein causing gelling in phloem sieve tube exudate from Cucurbita pepo. Biochim. biophys. Acta (Amst.) 257, 433–444 (1972)
Walker, T. S., Thaine, R.: Proteins and fine structural components in exudate from sieve tubes in Cucurbita pepo stems. Ann. Bot. 35, 773–790 (1971)
Weber, C., Kleinig, H.: Molecular weights of Cucurbita sieve tube proteins. Planta (Berl.) 99, 179–182 (1971)
Yapa, P. A. J., Spanner, D. C.: Isoelectric focusing of sieve tube protein. Planta (Berl.) 106, 369–373 (1972)
Zacharius, R. M., Zell, T. E., Morrison, J. H., Woodlock, J. J.: Glycoprotein staining following electrophoresis on acrylamide gels. Analyt. Biochem. 30, 148–152 (1969)
Author information
Authors and Affiliations
Additional information
Some results of the present article are contained in the “Staatsexamensarbeit” of J. B. and in the thesis of C. W.
Rights and permissions
About this article
Cite this article
Beyenbach, J., Weber, C. & Kleinig, H. Sieve-tube proteins from Cucurbita maxima . Planta 119, 113–124 (1974). https://doi.org/10.1007/BF00390885
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00390885