TY - JOUR
T1 - Self-preservation strategies during bacterial biomineralisation with reference to hydrozincite and implications for fossilisation of bacteria
AU - Ngwenya, Bryne T.
AU - Magennis, Marisa
AU - Podda, Francesca
AU - Gromov, Andrey
PY - 2014/10/24
Y1 - 2014/10/24
N2 - The induction of mineralisation by microbes has been widely demonstrated but whether induced biomineralisation leads to distinct morphologies indicative of microbial involvement remains an open question. For calcium carbonate, evidence suggests that microbial induction enhances sphere formation, but the mechanisms involved and the role of microbial surfaces are unknown. Here, we describe hydrozincite biominerals from Sardinia, Italy which apparently start life as smooth globules on cyanobacterial filaments, and evolve to spheroidal aggregates consisting of nanoplates. Complimentary laboratory experiments suggest that organic compounds are critical to produce this morphology, possibly by inducing aggregation of nanoscopic crystals or nucleation within organic globules produced by metabolising cells. These observations suggest that production of EPS by microbes may constitute an effective mechanism to enhance formation of porous spheroids that minimise cell entombment while also maintaining metabolite exchange. However, the high porosity arising from aggregation-based crystal growth likely facilitates rapid oxidation of entombed cells, reducing their potential to be fossilised.
AB - The induction of mineralisation by microbes has been widely demonstrated but whether induced biomineralisation leads to distinct morphologies indicative of microbial involvement remains an open question. For calcium carbonate, evidence suggests that microbial induction enhances sphere formation, but the mechanisms involved and the role of microbial surfaces are unknown. Here, we describe hydrozincite biominerals from Sardinia, Italy which apparently start life as smooth globules on cyanobacterial filaments, and evolve to spheroidal aggregates consisting of nanoplates. Complimentary laboratory experiments suggest that organic compounds are critical to produce this morphology, possibly by inducing aggregation of nanoscopic crystals or nucleation within organic globules produced by metabolising cells. These observations suggest that production of EPS by microbes may constitute an effective mechanism to enhance formation of porous spheroids that minimise cell entombment while also maintaining metabolite exchange. However, the high porosity arising from aggregation-based crystal growth likely facilitates rapid oxidation of entombed cells, reducing their potential to be fossilised.
U2 - 10.1098/rsif.2014.0845
DO - 10.1098/rsif.2014.0845
M3 - Article
SN - 1742-5689
VL - 11
JO - Journal of the Royal Society. Interface
JF - Journal of the Royal Society. Interface
IS - 100
M1 - 20140845
ER -