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bioRxiv · 10.1101/2024.09.03.611117

Description of a novel extremophile green algae, Chlamydomonas pacifica, and its potential as a biotechnology host

Dutra Molino, J. V.·Oliver, A.·Sethuram, H.·Kang, K.·Saucedo, B.·Diaz, C. J.·Gupta, A.·Jen, L. J.·Torres-tiji, Y.·Hidasi, N.·Badary, A.·Jenkins, H.·Fields, F. J.·Mayfield, S.
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Abstract

We present the comprehensive characterization of a newly identified microalga, Chlamydomonas pacifica, originally isolated from a soil sample in San Diego, CA, USA. This species showcases remarkable biological versatility, including a broad pH range tolerance (6-11.5), high thermal tolerance (up to 42{degrees}C), and salinity resilience (up to 2% NaCl). Its amenability to genetic manipulation and sexual reproduction via mating, particularly between the two opposing strains CC-5697 & CC-5699, now publicly available through the Chlamydomonas Resource Center, underscores its potential as a biotechnological chassis. The biological assessment of C. pacifica revealed versatile metabolic capabilities, including diverse nitrogen assimilation capability, motility and phototaxis. Genomic and transcriptomic analyses identified 17,829 genes within a 121 Mb genome, featuring a GC content of 61%. The codon usage of C. pacifica closely mirrors that of C. reinhardtii, indicating a conserved genetic architecture that supports a trend in codon preference with minor variations. Phylogenetic analyses position C. pacifica within the core-Reinhardtinia clade yet distinct from known Volvocales species. The lipidomic data revealed an abundance of triacylglycerols (TAGs), promising for biofuel applications and lipids for health-related benefits. Our investigation lays the groundwork for exploiting C. pacifica in biotechnological applications, from biofuel generation to synthesizing biodegradable plastics, positioning it as a versatile host for future bioengineering endeavors. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=117 SRC="FIGDIR/small/611117v2_ufig1.gif" ALT="Figure 1"> View larger version (44K): org.highwire.dtl.DTLVardef@1ead226org.highwire.dtl.DTLVardef@18af631org.highwire.dtl.DTLVardef@291c2borg.highwire.dtl.DTLVardef@f860ac_HPS_FORMAT_FIGEXP M_FIG Graphical Abstract C_FIG

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Dutra Molino, J. V., Oliver, A., Sethuram, H., Kang, K., Saucedo, B., Diaz, C. J., Gupta, A., Jen, L. J., Torres-tiji, Y., Hidasi, N., Badary, A., Jenkins, H., Fields, F. J., Mayfield, S.. 2024-09-04. Description of a novel extremophile green algae, Chlamydomonas pacifica, and its potential as a biotechnology host. https://doi.org/10.1101/2024.09.03.611117

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