Influence of diet on chitobiase-based production rates for the harpacticoid copepod Tigriopus californicus

Diflubenzuron (Dimilin) was tested, in the concentration range 0.1–5000 μg∙L−1, for possible injurious effects on the growth and photosynthesis of three chitin-producing (Thalassiosira weissflogii, T. norden-skioldii, Cyclotella cryptica) and one nonchitinaceous (Skeletonema costatum) diatoms. For comparison, the effects of the pesticide were also examined on adult survival and juvenile development of the harpacticoid copepod Tigriopus californicus. While the development of the copepod was hindered at concentrations of the order of 1–10 μg∙L−1, the diatoms were barely affected by Dimilin even at the highest concentration tested (5 mg∙L−1). We conclude that Dimilin acts specifically on insects and crustaceans as a larvicide by interfering with chitin deposition into cuticles during juvenile development through ecdysis. The lack of effect from Dimilin on the chitin-producing diatoms has suggested that the insecticide may not inhibit chitin biosynthesis per se as was previously believed, but that it presumably deregulates one or more of the larval postsynthetic processes responsible for chitin integration into cuticles.

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HERITABILITY OF SEX TENDENCY IN A HARPACTICOID COPEPOD, TIGRIOPUS CALIFORNICUS

Evolution ◽

10.1554/0014-3820(2002)056[1754:hostia]2.0.co;2 ◽

2002 ◽

Vol 56 (9) ◽

pp. 1754 ◽

Cited By ~ 4

Author(s):

Maarten J. Voordouw ◽

Bradley R. Anholt

Keyword(s):

Harpacticoid Copepod ◽

Tigriopus Californicus

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Stereochemistry of Astaxanthin Biosynthesis in the Marine Harpacticoid Copepod Tigriopus Californicus

Marine Drugs ◽

10.3390/md18100506 ◽

2020 ◽

Vol 18 (10) ◽

pp. 506

Author(s):

Alfonso Prado-Cabrero ◽

Ganjar Saefurahman ◽

John M. Nolan

Keyword(s):

High Performance ◽

Harpacticoid Copepod ◽

Model Organism ◽

Diode Array ◽

Hydroxyl Groups ◽

Tigriopus Californicus ◽

Nutritional Profile ◽

Array Detection ◽

First Time ◽

Feeding Sources

The harpacticoid copepod Tigriopus californicus has been recognized as a model organism for the study of marine pollutants. Furthermore, the nutritional profile of this copepod is of interest to the aquafeed industry. Part of this interest lies in the fact that Tigriopus produces astaxanthin, an essential carotenoid in salmonid aquaculture. Here, we study for the first time the stereochemistry of the astaxanthin produced by this copepod. We cultured T. californicus with different feeding sources and used chiral high-performance liquid chromatography with diode array detection (HPLC-DAD) to determine that T. californicus synthesizes pure 3S,3’S-astaxanthin. Using meso-zeaxanthin as feed, we found that the putative ketolase enzyme from T. californicus can work with β-rings with either 3R- or 3S-oriented hydroxyl groups. Despite this ability, experiments in the presence of hydroxylated and non-hydroxylated carotenoids suggest that T. californicus prefers to use the latter to produce 3S,3’S-astaxanthin. We suggest that the biochemical tools described in this work can be used to study the mechanistic aspects of the recently identified avian ketolase.

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A complete enzymatic capacity for biosynthesis of docosahexaenoic acid (DHA, 22 : 6n–3) exists in the marine Harpacticoida copepod Tigriopus californicus

Open Biology ◽

10.1098/rsob.200402 ◽

2021 ◽

Vol 11 (4) ◽

Author(s):

Naoki Kabeya ◽

Masanari Ogino ◽

Hideki Ushio ◽

Yutaka Haga ◽

Shuichi Satoh ◽

...

Keyword(s):

Fatty Acids ◽

Docosahexaenoic Acid ◽

De Novo ◽

Essential Fatty Acids ◽

Harpacticoid Copepod ◽

Fatty Acyl ◽

Trophic Levels ◽

Biosynthetic Pathways ◽

Tigriopus Californicus ◽

Front End

The long-standing paradigm establishing that global production of Omega-3 (n–3) long-chain polyunsaturated fatty acids (LC-PUFA) derived almost exclusively from marine single-cell organisms, was recently challenged by the discovery that multiple invertebrates possess methyl-end (or ω x) desaturases, critical enzymes enabling the biosynthesis of n–3 LC-PUFA. However, the question of whether animals with ω x desaturases have complete n–3 LC-PUFA biosynthetic pathways and hence can contribute to the production of these compounds in marine ecosystems remained unanswered. In the present study, we investigated the complete enzymatic complement involved in the n–3 LC-PUFA biosynthesis in Tigriopus californicus , an intertidal harpacticoid copepod. A total of two ω x desaturases, five front-end desaturases and six fatty acyl elongases were successfully isolated and functionally characterized. The T. californicus ω x desaturases enable the de novo biosynthesis of C 18 PUFA such as linoleic and α-linolenic acids, as well as several n–3 LC-PUFA from n–6 substrates. Functions demonstrated in front-end desaturases and fatty acyl elongases unveiled various routes through which T. californicus can biosynthesize the physiologically important arachidonic and eicosapentaenoic acids. Moreover, T. californicus possess a Δ4 desaturase, enabling the biosynthesis of docosahexaenoic acid via the ‘Δ4 pathway’. In conclusion, harpacticoid copepods such as T. californicus have complete n–3 LC-PUFA biosynthetic pathways and such capacity illustrates major roles of these invertebrates in the provision of essential fatty acids to upper trophic levels.

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Intensive production of the harpacticoid copepod Tigriopus californicus in a zero-effluent ‘green water’ bioreactor

Scientific Reports ◽

10.1038/s41598-021-04516-w ◽

2022 ◽

Vol 12 (1) ◽

Author(s):

Alfonso Prado-Cabrero ◽

Rafael Herena-Garcia ◽

John M. Nolan

Keyword(s):

Mass Production ◽

Closed Loop ◽

Harpacticoid Copepod ◽

Operation Time ◽

Dry Weight ◽

Green Water ◽

Tigriopus Californicus ◽

Wet Weight ◽

Tetraselmis Chui ◽

Acid Index

AbstractAquaculture is looking for substitutes for fishmeal and fish oil to maintain its continued growth. Zooplankton is the most nutritious option, but its controlled mass production has not yet been achieved. In this context, we have developed a monoalgal ‘green water’ closed-loop bioreactor with the microalgae Tetraselmis chui that continuously produced the harpacticoid copepod Tigriopus californicus. During 145 days of operation, the 2.2 m3 bioreactor produced 3.9 kg (wet weight) of Tigriopus with (dry weight) 0.79 ± 0.29% eicosapentaenoic acid (EPA), 0.82 ± 0.26% docosahexaenoic acid (DHA), 1.89 ± 0,60% 3S,3’S-astaxanthin and an essential amino acid index (EAAI) of 97% for juvenile Atlantic salmon. The reactor kept the pH stable over the operation time (pH 8.81 ± 0.40 in the algae phase and pH 8.22 ± 2.96 in the zooplankton phase), while constantly removed nitrate (322.6 mg L−1) and phosphate (20.4 mg L−1) from the water. As a result of the stable pH and nutrient removal, the bioreactor achieved zero effluent discharges. The upscaling of monoalgal, closed-loop ‘green water’ bioreactors could help standardize zooplankton mass production to supply the aquafeeds industry.

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