title: Low-substrate regulated microaerophilic behavior as a stress response of aquatic and soil bacteria.
abstract: Low-substrate regulated microaerophilic behavior (LSRMB) was observed in 10-54% of the bacteria isolated from several fresh-water lakes or ponds, subsurface soils, activated sludge, and Antarctic dry valley soils. Five Pseudomonas and two Bacillus type species showed LSRMB. A subsurface Pseudomonas jessenii strain was used as a model to show the metabolic interaction between substrate and oxygen concentrations, cell band movement, and the appearance of unique stress lipids and proteins. When the oxygen in the P. jessenii culture medium was increased from 11% to 100% saturation under atmospheric condition, the concentration of 17:0 cyclopropane fatty acid, a stress indicator, increased five-fold, and four unique proteins were also detected. This stress response occurred only in low-substrate media. It is our hypothesis that LSRMB is a common but under-appreciated trait of many aquatic and soil bacteria.
authors.affiliation: Department of Biology, Virginia Polytechnic Institute and State University, Blacksburg 24061, USA.
authors.forename: R
authors.initials: R
authors.lastname: Mazumder
authors.forename: H C
authors.initials: HC
authors.lastname: Pinkart
authors.forename: P S
authors.initials: PS
authors.lastname: Alban
authors.forename: T J
authors.initials: TJ
authors.lastname: Phelps
authors.forename: R E
authors.initials: RE
authors.lastname: Benoit
mesh_terms: D018407:Bacterial Physiological Phenomena / Q000187:drug effects; D001426:Bacterial Proteins / Q000032:analysis; D003470:Culture Media / Q000378:metabolism; D003521:Cyclopropanes / Q000032:analysis; D015180:Electrophoresis, Gel, Two-Dimensional; D005227:Fatty Acids / Q000032:analysis; D006360:Heat-Shock Proteins / Q000032:analysis; D010100:Oxygen / Q000494:pharmacology; D011549:Pseudomonas / Q000254:growth & development / Q000378:metabolism / Q000502:physiology; D012988:Soil Microbiology; D014871:Water Microbiology
chemical_list: D001426:Bacterial Proteins; D003470:Culture Media; D003521:Cyclopropanes; D005227:Fatty Acids; D006360:Heat-Shock Proteins; C028775:cyclopropane fatty acids; D010100:Oxygen