Biopolym. Cell. 2002; 18(4):319-323.
Genome and Its Regulation
Role of the exopolygalacturonase gene in interaction of Klebsiella oxytoca VN13 with wheat roots
1Kovtunovych G. L., 1Lar O. V., 1Kozyrovska N. O.
  1. Institute of Molecular Biology and Genetics, NAS of Ukraine
    150, Akademika Zabolotnoho Str., Kyiv, Ukraine, 03680

Abstract

An insertionally inactivated copy of the exopolygalacturonase (pehX) gene of K. oxytoca VN13 was used for the wild type gene substitution by reciprocal recombination. The ratio of the mutant and wild type bacterial cells in plant associated population has not being changed within a 4 week-period of the plant vegetation. Both types of cells penetrated inside the roots equally. Inactivation of the pehX-gene is not essential for the wheat root internal colonization, and this may be connected with substrate exospecificity of the enzyme and does not exclude a role of other pectinases in the penetrating process.

References

[1] Hallmann J, Quadt-Hallmann A, Mahaffee WF, Kloepper JW. Bacterial endophytes in agricultural crops. Can J Microbiol. 1997;43(10):895–914.
[2] Reinhold-Hurek B, Hurek T, Claeyssens M, van Montagu M. Cloning, expression in Escherichia coli, and characterization of cellulolytic enzymes of Azoarcus sp., a root-invading diazotroph. J Bacteriol. 1993;175(21):7056-65.
[3] Quadt-Hallmann A, Kloepper JW. Immunological detection and localization of the cotton endophyte Enterobacter asburiae JM22 in different plant species. Can J Microbiol. 1996;42(11):1144–54.
[4] Hazlewood GP, Gilbert HJ. Structure and function analysis of Pseudomonas plant cell wall hydrolases. Prog Nucleic Acid Res Mol Biol. 1998;61:211-41.
[5] Kovtunovych GL, Lar OV, Kordyum VA, Kleiner D, Kozyrovska NO. Enhancing the internal plant colonization rate with endophytic nitrogen-fixing bacteria. Biopolym Cell. 1999; 15(4):300-5.
[6] Kovtunovych G, Lar O, Kamalova S, Kordyum V, Kleiner D, Kozyrovska N. Correlation between pectate lyase activity and ability to penetrate into plant tissues by diazotrophic Klebsiella oxytoca VN 13. Plant and Soil. 1999; 260: 1-6.
[7] Kovtunovich GV, Lar OV, Kozyrovska NO. Cloning and structural analysis of the Klebsiella oxytoca VN13 peh gene. Biopolym Cell. 2000; 16(5):356-62.
[8] Penfold RJ, Pemberton JM. An improved suicide vector for construction of chromosomal insertion mutations in bacteria. Gene. 1992;118(1):145-6.
[9] Fellay R, Frey J, Krisch H. Interposon mutagenesis of soil and water bacteria: a family of DNA fragments designed for in vitro insertional mutagenesis of gram-negative bacteria. Gene. 1987;52(2-3):147-54.
[10] Sambrook J, Fritsch EF, Maniatis T. Molecular cloning: A laboratory manual. New York: Cold Spring Harbor Lab. press, 1989.
[11] Nishimura A, Morita M, Nishimura Y, Sugino Y. A rapid and highly efficient method for preparation of competent Escherichia coli cells. Nucleic Acids Res. 1990;18(20):6169.
[12] He SY, Collmer A. Molecular cloning, nucleotide sequence, and marker exchange mutagenesis of the exo-poly-alpha-D-galacturonosidase-encoding pehX gene of Erwinia chrysanthemi EC16. J Bacteriol. 1990;172(9):4988-95.
[13] Brooks AD, He SY, Gold S, Keen NT, Collmer A, Hutcheson SW. Molecular cloning of the structural gene for exopolygalacturonate lyase from Erwinia chrysanthemi EC16 and characterization of the enzyme product. J Bacteriol. 1990;172(12):6950-8.