TY - JOUR
T1 - Characterization of a high lipid-producing thermotolerant marine photosynthetic pico alga from genus Picochlorum (Trebouxiophyceae)
AU - Mucko, Maja
AU - Padisák, Judit
AU - Gligora Udovič, Marija
AU - Pálmai, Tamás
AU - Novak, Tihana
AU - Medić, Nikola
AU - Gašparović, Blaženka
AU - Peharec Štefanić, Petra
AU - Orlić, Sandi
AU - Ljubešić, Zrinka
N1 - Publisher Copyright:
© 2020 British Phycological Society.
PY - 2020/10/1
Y1 - 2020/10/1
N2 - A new marine strain of picoplanktonic algae, PMPFPPE4, was isolated from a mixed net-phytoplankton sample taken from the upper euphotic layer of the southeastern Adriatic Sea. Evaluation of the new strain included morphological investigation (by light and electron microscopy), phylogenetic analysis (utilizing plastid 16S rRNA and nuclear 18S rRNA genes), and physiological characterization (screening of pigment/lipid composition and capturing photosynthesis measurements). The new strain was proven to belong to the genus Picochlorum and the lipid composition revealed an unexpected accumulation of triacylglycerols, indicating an evolutionary adaptation for growth under unfavourable conditions. In addition, lipid remodelling in the exponential to stationary growth phase was characterized by an increased share of membrane-forming digalactosyldiacylglycerols and phosphatidylcholines. Maximum photosynthetic activity measured was at 30°C, but the most rapid increase of photosynthetic activity was at lower temperatures (15–20°C). Moreover, the thermotolerant strain did not exhibit photoinhibition below 40°C and survived a one-month cultivation period in complete darkness. The strain’s survival in low light and dark conditions suggests a potential shift from autotrophy to mixotrophy under unfavourable growth conditions. Thus, the unique physiological attributes represented by a high growth rate, thermotolerance, phototolerance and high triacylglycerol synthesis may render the strain highly attractive for biofuel production and growth in large outdoor systems.
AB - A new marine strain of picoplanktonic algae, PMPFPPE4, was isolated from a mixed net-phytoplankton sample taken from the upper euphotic layer of the southeastern Adriatic Sea. Evaluation of the new strain included morphological investigation (by light and electron microscopy), phylogenetic analysis (utilizing plastid 16S rRNA and nuclear 18S rRNA genes), and physiological characterization (screening of pigment/lipid composition and capturing photosynthesis measurements). The new strain was proven to belong to the genus Picochlorum and the lipid composition revealed an unexpected accumulation of triacylglycerols, indicating an evolutionary adaptation for growth under unfavourable conditions. In addition, lipid remodelling in the exponential to stationary growth phase was characterized by an increased share of membrane-forming digalactosyldiacylglycerols and phosphatidylcholines. Maximum photosynthetic activity measured was at 30°C, but the most rapid increase of photosynthetic activity was at lower temperatures (15–20°C). Moreover, the thermotolerant strain did not exhibit photoinhibition below 40°C and survived a one-month cultivation period in complete darkness. The strain’s survival in low light and dark conditions suggests a potential shift from autotrophy to mixotrophy under unfavourable growth conditions. Thus, the unique physiological attributes represented by a high growth rate, thermotolerance, phototolerance and high triacylglycerol synthesis may render the strain highly attractive for biofuel production and growth in large outdoor systems.
KW - Morphology
KW - Picochlorum
KW - photosynthetic picoeukaryotes
KW - phylogeny
KW - physiology
UR - http://www.scopus.com/inward/record.url?scp=85089296358&partnerID=8YFLogxK
U2 - 10.1080/09670262.2020.1757763
DO - 10.1080/09670262.2020.1757763
M3 - Article
AN - SCOPUS:85089296358
SN - 0967-0262
VL - 55
SP - 384
EP - 399
JO - European Journal of Phycology
JF - European Journal of Phycology
IS - 4
ER -