Abstract
The enzyme β-cystathionase catalyzes the conversion of cystathionine to homocysteine in both plants and bacteria. Preparations of this enzyme taken from both Salmonella and spinach (Spinacia oleracea L.) have been shown to be irreversibly inhibited by low concentrations of rhizobitoxine (RT), a chlorosis-inducing phytotoxin produced by some strains of soybean bradyrhizobia. The sensitivities of β-cystathionase from bradyrhizobia and soybean are not well characterized. Therefore, we purified β-cystathionase from selected bradyrhizobia and soybean genotypes that have been shown to exhibit differences in RT production and apparent RT sensitivities, respectively. Enzyme purified from E. coli strain DH52 was used for comparison. The enzymes differed in their physiological properties and RT sensitivities. Overall, the β-cystathionase enzymes purified from bradyrhizobia were more sensitive to RT than were those from the soybean cultivars. Kinetic studies showed that the nature of the RT-induced inhibition also differed between the two sources. The enzymes from bradyrhizobia exhibited inhibition that was [RT]-dependent, whereas the enzymes from soybean showed a time-dependent inhibition. These contrasting characteristics may in part reflect differences in active site accessibility, amino acid components, and associated RT diffusion rates. However, in all cases the inhibition caused by RT showed a typical substrate-competitive inhibition pattern.
Published as Paper No. 1571 in the Journal Series of the Delaware Agricultural Experiment Station.
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Abbreviations
- RT:
-
rhizobitoxine
- PLP:
-
pyridoxal phosphate
- DTT:
-
dithioerythritol
- PMSF:
-
phenylmethylsul-fonyl fluoride
- HTP:
-
hydroxyapatite
References
Datko A H and Mudd S H 1982 Methionine biosynthesis in Lemna: inhibitor studies. Plant Physiol. 69, 1070–1076.
Deutscher M P 1990 Guide to Protein Purification. Acad. Press. Inc., San Diego, USA.
Dwivedi C M, Ragin R C and Uren J R 1982 Cloning, purification, and charcterization of 0-cystathionase from Escherichia coli. Biochemistry. 21, 3046–3069.
Gentry-Weeks C R, Keith J M and Thompson J 1993 Toxicity of Bor-detella aviumβ-Cystathionase toward MC3T3-EI Osteogenic Cells. J. Biol. Chem. 268, 7298–7314.
Giovanelli J and Mudd S H 1971 Transsulfuration in higher plants: Partial purification and properties of β-cystathionase of spinach. Biochim. Biophys. Acta 227, 654–670.
Giovanelli J, Owens L D and Mudd S H 1971 Mechanism of inhibition of spinach β-cystathionase by rhizobitoxine. Biochem. Biophys. Acta 227, 671–684.
Giovanelli J, Owens L D and Mudd S H 1972 β-Cystathionase-in vivo inactivation by rhizobitoxine and role of the enzyme in methionine biosynthesis in corn seedlings. Plant Physiol. 51, 492–503.
Giovanelli J 1987 Cystathionine β-lyase from spinach. Meth. Enzy-mol. 143, 443–449.
Guggenheims 1971 β-Cystathionase (Salmonella) Meth.Enzymol. 17B, 439–442.
Moss D W 1979 Isoenzyme analysis. Spottiswoode Ballantyne Ltd., Colchester, UK.
Negrutiu I, De Brouwer D, Dirks R and Jacobs M 1985 Amino acid auxotrophs from protoplast cultures of Nicotiana plumbaginifo-lia, Viviani. Mol. Gen. Genet. 199, 330–337.
Owens L D, Guggenheim S and Hilton J L 1968 Rhizobium- synthesized photoxin: an inhibitor of β-cystathionase in Salmonella typhimurium. Biochem. Biophys. Acta 158, 219–225.
Ruan X and Peters N K 1991 Rapid and sensitive assay for the phytotoxin, rhizobitoxine. Appl. Environ. Microbiol. 57, 2097–2100.
Teaney G B III and J J Fuhrmann 1992 Soybean response to nodu-lation by bradyrhizobia differing in rhizobitoxine phenotype. Plant and Soil 145, 275–285.
Uren J R 1987 Cystathionase &#z00B2;-lyase from Escherichia coli. Meth. Enzymol. 143, 483–486.
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© 1996 Springer Science+Business Media Dordrecht
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Xiong, K., Fuhrmann, J.J. (1996). Comparison of rhizobitoxine-induced inhibition of β-cystathionase from different bradyrhizobia and soybean genotypes. In: Elkan, G.H., Upchurch, R.G. (eds) Current Issues in Symbiotic Nitrogen Fixation. Developments in Plant and Soil Sciences, vol 72. Springer, Dordrecht. https://doi.org/10.1007/978-94-011-5700-1_7
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DOI: https://doi.org/10.1007/978-94-011-5700-1_7
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