Iron effects on colonization behavior, motility, and enzymatic activity of marine bacteria.
Iron availability in the ocean has been shown to affect the growth and production of phytoplankton and free-living bacteria. A large fraction of marine bacteria are specialized in colonizing and living on particles and aggregates, but the effects of iron limitation on these bacteria are not fully known. We conducted laboratory experiments to study the effects of iron availability on particle colonization behavior, motility, and enzymatic activities of 4 strains of marine bacteria. Iron depletion reduced the bacterial particle colonization rate by 1.7%-43.1%, which could be attributed to reduced swimming speeds in 2 of the 4 strains. Protease activity was not affected by iron availability. However, attached bacteria did show higher protease activities than their free counterparts. Our results suggest that iron limitation in the ocean could in some cases reduce bacteria-particle interactions by reducing bacterial motility and colonization rate.
Tang
Kam W
KW
Virginia Institute of Marine Science, 1208 Greate Road, Gloucester Point, Virginia 23062, USA. kamtang@vims.edu
Grossart
Hans-Peter
HP
D001419:Bacteria / Q000187:drug effects* / Q000254:growth & development* / Q000378:metabolism; D018407:Bacterial Physiological Phenomena / Q000187:drug effects; D001426:Bacterial Proteins / Q000378:metabolism; D007501:Iron / Q000494:pharmacology*; D009792:Oceans and Seas; D010447:Peptide Hydrolases / Q000378:metabolism; D012623:Seawater / Q000382:microbiology*
D001426:Bacterial Proteins; D007501:Iron; D010447:Peptide Hydrolases