Characterization of Leptospiral Chemoreceptors Using a Microscopic Agar Drop Assay.
Bacterial chemotaxis is induced by sensing chemical stimuli via chemoreceptors embedded in the cytoplasmic membrane, enabling the cells to migrate toward nutrients or away from toxins. The chemoreceptors of Escherichia coli and Salmonella spp. have been well studied and are functionally classified on the basis of detectable substrates. The spirochete Leptospira possesses more than ten chemoreceptors and shows attractive or repellent responses against some sugars, amino acids, and fatty acids. However, the roles of these chemoreceptors have not been investigated. In this study, we conducted a chemotaxis assay called microscopic agar drop assay in combination with competition experiments, determining whether two kinds of attractants are recognized by the same type of chemoreceptor in the saprophytic Leptospira strain, Leptospira biflexa. Analyzing the competition effect observed between several pairs of chemicals, we found that L. biflexa senses sugars via chemoreceptors different from those that sense amino acids and fatty acids.
Department of Applied Physics, Graduate School of Engineering, Tohoku University, 6-6-05 Aoba, Aoba-ku, Miyagi, Sendai, 980-8579, Japan.
Samia
S
Affroze
Department of Applied Physics, Graduate School of Engineering, Tohoku University, 6-6-05 Aoba, Aoba-ku, Miyagi, Sendai, 980-8579, Japan.|Department of Microbiology and Hygiene, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh, 2202, Bangladesh.
Md Shafiqul
MS
Islam
Department of Applied Physics, Graduate School of Engineering, Tohoku University, 6-6-05 Aoba, Aoba-ku, Miyagi, Sendai, 980-8579, Japan.
Kyosuke
K
Takabe
Department of Applied Physics, Graduate School of Engineering, Tohoku University, 6-6-05 Aoba, Aoba-ku, Miyagi, Sendai, 980-8579, Japan.
Seishi
S
Kudo
Department of Applied Physics, Graduate School of Engineering, Tohoku University, 6-6-05 Aoba, Aoba-ku, Miyagi, Sendai, 980-8579, Japan. naka@bp.apph.tohoku.ac.jp.
Shuichi
S
Nakamura
D000596:Amino Acids / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001681:Biological Assay / Q000295:instrumentation / Q000379:methods*; D050260:Carbohydrate Metabolism; D002633:Chemotaxis; D007919:Leptospira / Q000235:genetics / Q000502:physiology*; D008853:Microscopy / Q000379:methods*
D000596:Amino Acids; D001426:Bacterial Proteins