TY - JOUR
T1 - Rapid adaptation of harmful cyanobacteria to rising CO2
AU - Sandrini, Giovanni
AU - Ji, Xing
AU - Verspagen, Jolanda M. H.
AU - Tann, Robert P.
AU - Slot, Pieter C.
AU - Luimstra, Veerle M.
AU - Schuurmans, J. Merijn
AU - Matthijs, Hans C. P.
AU - Huisman, Jef
N1 - 6174, AqE; Data archiving: data archived at UvA
PY - 2016
Y1 - 2016
N2 - Rising atmospheric CO2 concentrations are likely to affect many ecosystems worldwide. However, to what extent elevated CO2 will induce evolutionary changes in photosynthetic organisms is still a major open question. Here, we show rapid microevolutionary adaptation of a harmful cyanobacterium to changes in inorganic carbon (Ci) availability. We studied the cyanobacterium Microcystis, a notorious genus that can develop toxic cyanobacterial blooms in many eutrophic lakes and reservoirs worldwide. Microcystis displays genetic variation in the Ci uptake systems BicA and SbtA, where BicA has a low affinity for bicarbonate but high flux rate, and SbtA has a high affinity but low flux rate. Our laboratory competition experiments show that bicA + sbtA genotypes were favored by natural selection at low CO2 levels, but were partially replaced by the bicA genotype at elevated CO2. Similarly, in a eutrophic lake, bicA + sbtA strains were dominant when Ci concentrations were depleted during a dense cyanobacterial bloom, but were replaced by strains with only the high-flux bicA gene when Ci concentrations increased later in the season. Hence, our results provide both laboratory and field evidence that increasing carbon concentrations induce rapid adaptive changes in the genotype composition of harmful cyanobacterial blooms.
AB - Rising atmospheric CO2 concentrations are likely to affect many ecosystems worldwide. However, to what extent elevated CO2 will induce evolutionary changes in photosynthetic organisms is still a major open question. Here, we show rapid microevolutionary adaptation of a harmful cyanobacterium to changes in inorganic carbon (Ci) availability. We studied the cyanobacterium Microcystis, a notorious genus that can develop toxic cyanobacterial blooms in many eutrophic lakes and reservoirs worldwide. Microcystis displays genetic variation in the Ci uptake systems BicA and SbtA, where BicA has a low affinity for bicarbonate but high flux rate, and SbtA has a high affinity but low flux rate. Our laboratory competition experiments show that bicA + sbtA genotypes were favored by natural selection at low CO2 levels, but were partially replaced by the bicA genotype at elevated CO2. Similarly, in a eutrophic lake, bicA + sbtA strains were dominant when Ci concentrations were depleted during a dense cyanobacterial bloom, but were replaced by strains with only the high-flux bicA gene when Ci concentrations increased later in the season. Hence, our results provide both laboratory and field evidence that increasing carbon concentrations induce rapid adaptive changes in the genotype composition of harmful cyanobacterial blooms.
KW - national
U2 - 10.1073/pnas.1602435113
DO - 10.1073/pnas.1602435113
M3 - Article
SN - 0027-8424
VL - 113
SP - 9315
EP - 9320
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 33
ER -