title: Influence of heavy metals on microbial growth kinetics including lag time: mathematical modeling and experimental verification.
abstract: Heavy metals can significantly affect the kinetics of substrate biodegradation and microbial growth, including lag times and specific growth rates. A model to describe microbial metabolic lag as a function of the history of substrate concentration has been previously described by Wood et al. (Water Resour Res 31:553-563) and Ginn (Water Resour Res 35:1395-1408). In the present study, this model is extended by including the effect of heavy metals on metabolic lag by developing an inhibitor-dependent functional to account for the metabolic state of the microorganisms. The concentration of the inhibiting metal is explicitly incorporated into the functional. The validity of the model is tested against experimental data on the effects of zinc on Pseudomonas species isolated from Lake Coeur d'Alene sediments, Idaho, U.S.A., as well as the effects of nickel or cobalt on a mixed microbial culture collected from the aeration tank of a wastewater treatment plant in Athens, Greece. The simulations demonstrate the ability to incorporate the effect of metals on metabolism through lag, yield coefficient, and specific growth rates. The model includes growth limitation due to insufficient transfer of oxygen into the growth medium.
authors.affiliation: Department of Civil and Environmental Engineering, University of California at Davis, Davis, California 95616, USA. sssengor@gmail.com
authors.forename: S Sevinç
authors.initials: SS
authors.lastname: Sengör
authors.forename: Sutapa
authors.initials: S
authors.lastname: Barua
authors.forename: Petros
authors.initials: P
authors.lastname: Gikas
authors.forename: Timothy R
authors.initials: TR
authors.lastname: Ginn
authors.forename: Brent
authors.initials: B
authors.lastname: Peyton
authors.forename: Rajesh K
authors.initials: RK
authors.lastname: Sani
authors.forename: Nicolas F
authors.initials: NF
authors.lastname: Spycher
mesh_terms: D000085:Acetates / Q000032:analysis; D001673:Biodegradation, Environmental / Q000187:drug effects; D019015:Geologic Sediments / Q000737:chemistry; D007700:Kinetics; D019216:Metals, Heavy / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity*; D008954:Models, Biological; D010100:Oxygen / Q000032:analysis; D011549:Pseudomonas / Q000187:drug effects* / Q000254:growth & development* / Q000378:metabolism; D012989:Soil Pollutants / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity
chemical_list: D000085:Acetates; D019216:Metals, Heavy; D012989:Soil Pollutants; D014874:Water Pollutants, Chemical; D010100:Oxygen