Ammonia-limited conditions cause of Thaumarchaeal dominance in volcanic grassland soil

TY - JOUR

T1 - Ammonia-limited conditions cause of Thaumarchaeal dominance in volcanic grassland soil

AU - Daebeler, Anne

AU - Bodelier, Paul L.E.

AU - Hefting, Mariet M.

AU - Laanbroek, Hendrikus J.

N1 - 5800, ME; Data archiving: Data archived at MDA

PY - 2015

Y1 - 2015

N2 - The first step of nitrification is carried out by ammonia-oxidizing bacteria (AOB) and archaea (AOA). It is largely unknown, by which mechanisms these microbes are capable of coexistence and how their respective contribution to ammonia oxidation may differ with varying soil characteristics. To determine how different levels of ammonium availability influence the extent of archaeal and bacterial contributions to ammonia oxidation, microcosm incubations with controlled ammonium levels were conducted. Net nitrification was monitored and ammonia oxidizer communities were quantified. Additionally, the nitrification inhibitor allylthiourea (ATU) was applied to discriminate between archaeal and bacterial contributions to soil ammonia oxidation. Thaumarchaeota, which were the only ammonia oxidizers detectable at the start of the incubation, grew in all microcosms, but AOB later became detectable and grew as well. Low and high additions of ammonium increasingly stimulated AOB growth, while AOA were only stimulated by the low addition. Treatment with ATU had no effect on net nitrification and sizes of ammonia-oxidizing communities suggesting that the effective concentration of ATU to discriminate between archaeal and bacterial ammonia oxidation is not the same in different soils. Our results support the niche differentiating potential of ammonium concentration for AOA and AOB and we conclude that ammonium limitation can be a major reason for absence of detectable AOB in soil.Keywordsammonia-oxidizing archaeaammonia-oxidizing bacterianitrificationallylthioureaammonium© FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions{at}oup.com

AB - The first step of nitrification is carried out by ammonia-oxidizing bacteria (AOB) and archaea (AOA). It is largely unknown, by which mechanisms these microbes are capable of coexistence and how their respective contribution to ammonia oxidation may differ with varying soil characteristics. To determine how different levels of ammonium availability influence the extent of archaeal and bacterial contributions to ammonia oxidation, microcosm incubations with controlled ammonium levels were conducted. Net nitrification was monitored and ammonia oxidizer communities were quantified. Additionally, the nitrification inhibitor allylthiourea (ATU) was applied to discriminate between archaeal and bacterial contributions to soil ammonia oxidation. Thaumarchaeota, which were the only ammonia oxidizers detectable at the start of the incubation, grew in all microcosms, but AOB later became detectable and grew as well. Low and high additions of ammonium increasingly stimulated AOB growth, while AOA were only stimulated by the low addition. Treatment with ATU had no effect on net nitrification and sizes of ammonia-oxidizing communities suggesting that the effective concentration of ATU to discriminate between archaeal and bacterial ammonia oxidation is not the same in different soils. Our results support the niche differentiating potential of ammonium concentration for AOA and AOB and we conclude that ammonium limitation can be a major reason for absence of detectable AOB in soil.Keywordsammonia-oxidizing archaeaammonia-oxidizing bacterianitrificationallylthioureaammonium© FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions{at}oup.com

KW - Ammonia

KW - Ammonium Compounds

KW - Archaea

KW - Bacteria

KW - Grassland

KW - Nitrification

KW - Oxidation-Reduction

KW - Soil

KW - Soil Microbiology

KW - Thiourea

KW - national

UR - http://mda.vliz.be/mda/directlink.php?fid=VLIZ_00000353_1400848687

U2 - 10.1093/femsec/fiv014

DO - 10.1093/femsec/fiv014

M3 - Article

C2 - 25764462

SN - 0168-6496

VL - 91

JO - FEMS Microbiology Ecology

JF - FEMS Microbiology Ecology

IS - 3

M1 - fiv014

ER -