Soil bacteria and protists show different sensitivity to polycyclic aromatic hydrocarbons at controlled chemical activity

TY - JOUR

T1 - Soil bacteria and protists show different sensitivity to polycyclic aromatic hydrocarbons at controlled chemical activity

AU - Winding, Anne

AU - Modrzyński, Jakub Jan

AU - Christensen, Jan H.

AU - Brandt, Kristian K.

AU - Mayer, Philipp

PY - 2019

Y1 - 2019

N2 - This study linked growth inhibition of soil bacteria and protists to the chemical activity (a) of polycyclic aromatic hydrocarbons (PAHs) and compared the sensitivities of bacteria and protists. Passive dosing from pre-loaded silicone provided well-defined and constant a of PAHs in independent tests. Single-species growth inhibition with two bacterial (Pseuodomonas fluorescens DR54 and Sinorhizobium meliloti) and two protist (Cercomonas longicauda and Acanthamoeba castellanii) strains at maximum a (amax) of nine and four PAHs, respectively, showed no inhibition of PAHs with amax below 0.1 (pyrene and anthracene), while growth inhibition was observed for PAHs with amax above 0.1 (e.g. fluorene, fluoranthene and naphthalene). The bacteria were less sensitive than the protists. Soil bacterial community-level growth inhibition by naphthalene was in good agreement with single-species data, but also indicated the presence of sensitive bacteria that were inhibited by a below 0.05 and increasing pre-exposure time giving higher inhibition. The a of 50% inhibition (Ea50) was 0.434 and 0.329 for 0.5 and 4 h pre-exposure time, respectively. Invertebrates tended to be more sensitive than single-celled organisms tested here. This suggests that PAH exposure leads to differential toxicity in soil biota, which may affect soil food web structure and cycling of organic matter.

AB - This study linked growth inhibition of soil bacteria and protists to the chemical activity (a) of polycyclic aromatic hydrocarbons (PAHs) and compared the sensitivities of bacteria and protists. Passive dosing from pre-loaded silicone provided well-defined and constant a of PAHs in independent tests. Single-species growth inhibition with two bacterial (Pseuodomonas fluorescens DR54 and Sinorhizobium meliloti) and two protist (Cercomonas longicauda and Acanthamoeba castellanii) strains at maximum a (amax) of nine and four PAHs, respectively, showed no inhibition of PAHs with amax below 0.1 (pyrene and anthracene), while growth inhibition was observed for PAHs with amax above 0.1 (e.g. fluorene, fluoranthene and naphthalene). The bacteria were less sensitive than the protists. Soil bacterial community-level growth inhibition by naphthalene was in good agreement with single-species data, but also indicated the presence of sensitive bacteria that were inhibited by a below 0.05 and increasing pre-exposure time giving higher inhibition. The a of 50% inhibition (Ea50) was 0.434 and 0.329 for 0.5 and 4 h pre-exposure time, respectively. Invertebrates tended to be more sensitive than single-celled organisms tested here. This suggests that PAH exposure leads to differential toxicity in soil biota, which may affect soil food web structure and cycling of organic matter.

KW - bioavailability

KW - chemical activity

KW - PAH

KW - Protista

KW - Soil microorganisms

KW - toxicity

UR - http://www.scopus.com/inward/record.url?scp=85074620977&partnerID=8YFLogxK

U2 - 10.1093/femsle/fnz214

DO - 10.1093/femsle/fnz214

M3 - Journal article

C2 - 31598655

AN - SCOPUS:85074620977

SN - 0378-1097

VL - 366

JO - FEMS Microbiology Letters

JF - FEMS Microbiology Letters

IS - 17

M1 - fnz214

ER -