Role of pili (fimbriae) in attachment of Bradyrhizobium japonicum to soybean roots
Pili (fimbriae) were observed on cells of each of the five strains of Bradyrhizobium japonicum and the one strain of Rhizobium trifolii examined. Pili on B. japonicum were about 4 nm in diameter and polarly expressed. Piliated cells were estimated by transmission electron microscopy and hydrophobic attachment to polystyrene to constitute only a small percentage of the total population. The proportion of piliated cells in these populations was dependent on culture age in some strains. Piliated B. japonicum cells were selectively and quantitatively removed from suspension when cultures were incubated with either soybean roots or hydrophobic plastic surfaces, indicating that pili were involved in the attachment of the bacteria to these surfaces. Pili from B. japonicum 110 ARS were purified and found to have a subunit molecular weight of approximately 21,000. Treatment of B. japonicum suspensions with antiserum against the isolated pili reduced attachment to soybean roots by about 90% and nodulation by about 80%. Pili appear to be important mediators of attachment of B. japonicum to soybean roots under the conditions examined.
- Research Organization:
- Battelle-C.F. Kettering Research Lab., Yellow Springs, OH
- DOE Contract Number:
- AC02-81ER10895
- OSTI ID:
- 5014283
- Journal Information:
- Appl. Environ. Microbiol.; (United States), Journal Name: Appl. Environ. Microbiol.; (United States) Vol. 52:1; ISSN AEMID
- Country of Publication:
- United States
- Language:
- English
Similar Records
Basis for the competitiveness of rhizobium japonicum in nodulation of soybean. Final progress report
Growth of fast- and slow-growing rhizobia on ethanol. [Bradyrhizobium sp. ; Rhizobium meliloti; Rhizobium loti; Rhizobium leguminosarum; Rhizobium fredii; Bradyrhizobium japonicum]