Polyhadroxyalkanoates –microbial polyesters with a complex protective effect against diverse stress factors

Polyhadroxyalkanoates –microbial polyesters with a complex protective effect against diverse stress factors

Abstract

Polyhydroxyalkanoates (PHAs) are hydrophobic polyesters produced and accumulated by numerous microorganisms in a form of intracellular granules filled with the polymer and covered by a layer of proteins. The polymer content of bacteria can reach up to 90 % of the weight of cellular dry matter. In our recent work, we have confirmed experimentally that PHAs granules do not serve only as a source of carbon or energy but also as a cell component with a complex protective performance. PHAs accumulating bacteria cells are synthesizing and degrading the polymers simultaneously. We have confirmed that the monomer of PHAs, which is found in the polymer-accumulating bacterial in a substantial amount, serves as a chemical chaperone and a cryo- protective solute. Furthermore, we have revealed that the protective function of the polymer against various stressors such as non-optimal pH, high and low temperature, osmotic up- and down-shock, UV exposure etc. is conditioned by the native amorphous state of PHAs. This liquid-like state of PHAs, found only in-vivo, is involved in the adaptation of cells supporting them to survive sudden changes of the environment.

Polyhydroxyalkanoates (PHAs) are hydrophobic polyesters produced and accumulated by numerous microorganisms in a form of intracellular granules filled with the polymer and covered by a layer of proteins. The polymer content of bacteria can reach up to 90 % of the weight of cellular dry matter. In our recent work, we have confirmed experimentally that PHAs granules do not serve only as a source of carbon or energy but also as a cell component with a complex protective performance. PHAs accumulating bacteria cells are synthesizing and degrading the polymers simultaneously. We have confirmed that the monomer of PHAs, which is found in the polymer-accumulating bacterial in a substantial amount, serves as a chemical chaperone and a cryo- protective solute. Furthermore, we have revealed that the protective function of the polymer against various stressors such as non-optimal pH, high and low temperature, osmotic up- and down-shock, UV exposure etc. is conditioned by the native amorphous state of PHAs. This liquid-like state of PHAs, found only in-vivo, is involved in the adaptation of cells supporting them to survive sudden changes of the environment.

PHA, stress factors, protectants, intracellular granule

PHA, stress factors, protectants, intracellular granule

SLANINOVÁ, E.; SEDLÁČEK, P.; OBRUČA, S.

2019

13.11.2018

Tiskárna Didot, spol. s. r. o.

Trnkova 119, 628 00 Brno-Líšeň

978-80-210-9069-9

XIX. setkání biochemiků a molekulárních biologů

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