We just wrapped a 10-day run with CRISPR-edited Nannochloropsis in a closed 50 L photobioreactor expressing an antiviral peptide, and the stability under fluctuating salinity surprised me. I’m curious if anyone has compared chloroplast vs nuclear expression in marine microalgae for biopharm production, or navigated the regulatory maze for contained dockside mesocosms?
In our Nannochloropsis work, chloroplast expression gave higher accumulation but no glycosylation, so we only moved to nuclear when we needed secretion — nice that your 50 L run held under “fluctuating salinity”. For dockside mesocosms, the single thing that sped approval was getting the harbor authority to sign a no‑discharge memo up front and attaching it to the IBC packet. @OP are you targeting a glycosylated antiviral peptide or a small non‑modified one?
I’m with @ethan_ocean675 on going nuclear when you need secretion; one thing that sped our dockside mesocosm sign-off was filing a one-page no-release risk memo with the IBC and looping in the harbormaster on day one — cut review time a lot. Are you aiming for a glycosylated antiviral peptide?
With a 10‑day 50 L run and “fluctuating salinity,” I’ve seen chloroplast expression stay steadier than nuclear; we only switch nuclear when export is mission‑critical. For dockside, framing the mesocosm as no‑discharge under TSCA and pairing IBC minutes with a harbor‑master letter moved approvals fastest — did you try an EPA MCAN pre‑consult, @ethan_ocean675?
Given the 10‑day run and “fluctuating salinity,” plastid expression pairs well when you’re collecting cells rather than chasing secreted product, and organelle confinement tends to read cleaner to reviewers in closed dockside systems. If the peptide truly needs secretion/glycans, nuclear’s the trade, but expect more variability. Are you targeting intracellular recovery or export?