# L'effet de la tryptone sur la croissance et la bioluminescence.



# New Page



# Expérimentation 1

**1) Bibliographie**

**3) Résultats**

[![image.png](https://wiki.fablab.sorbonne-universite.fr/BookStack/uploads/images/gallery/2025-05/scaled-1680-/Eg7image.png) ](https://wiki.fablab.sorbonne-universite.fr/BookStack/uploads/images/gallery/2025-05/Eg7image.png)[![pSaimage.png](https://wiki.fablab.sorbonne-universite.fr/BookStack/uploads/images/gallery/2025-05/scaled-1680-/psaimage.png)](https://wiki.fablab.sorbonne-universite.fr/BookStack/uploads/images/gallery/2025-05/psaimage.png)

**Figure 1:** Bioluminescence de Rattail en fonction du tryptone  **Figure 2 :** Les cultures de Rattail en fonction du tryptone

<table border="1" id="bkmrk-milieu-utilis%C3%A9%C2%A0-biol" style="border-collapse: collapse; width: 100%; height: 178.781px;"><colgroup><col style="width: 50%;"></col><col style="width: 50%;"></col></colgroup><tbody><tr style="height: 29.7969px;"><td style="height: 29.7969px;">**Milieu utilisé** </td><td style="height: 29.7969px;">**Bioluminescence**</td></tr><tr style="height: 29.7969px;"><td style="height: 29.7969px;">Sans tryptone </td><td style="height: 29.7969px;">+</td></tr><tr style="height: 29.7969px;"><td style="height: 29.7969px;">Tryptone 20g/L</td><td style="height: 29.7969px;">++</td></tr><tr style="height: 29.7969px;"><td style="height: 29.7969px;">Tryptone 30g/L</td><td style="height: 29.7969px;">+++</td></tr><tr style="height: 29.7969px;"><td style="height: 29.7969px;">Tryptone 40g/L</td><td style="height: 29.7969px;">+++</td></tr><tr style="height: 29.7969px;"><td style="height: 29.7969px;">Tryptone 50g/L</td><td style="height: 29.7969px;">+++</td></tr></tbody></table>

**4) Discussion**

On observe une forte bioluminescence à partir de 30g/L de tryptone ce qui concorde avec ce qu'il y a dans la littérature. Sans tryptone, on observe une bioluminescence qui est nettement moins élevée. Le tryptone est donc nécessaire au bon fonctionnement de la luciférase bactérienne.

<span class="relative -mx-px my-[-0.2rem] rounded px-px py-[0.2rem] transition-colors duration-100 ease-in-out">Un milieu enrichi en **tryptone (≈ 5 g/L)**, combiné à du **glycerol (3 g/L)**, **yeast extract (5 g/L)** et **NaCl (30 g/L)** favorise une croissance efficace de *P. phosphoreum* T3 et Q67, atteignant respectivement OD ≈ 0,85 et 1,25 en 12 h à 22 °C</span> <span class="" data-state="closed"><span class="ms-1 inline-flex max-w-full items-center relative top-[-0.094rem] animate-[show_150ms_ease-in]">[<span class="relative start-0 bottom-0 flex h-full w-full items-center"><span class="flex h-4 w-full items-center justify-between absolute"><span class="max-w-full grow truncate overflow-hidden text-center">sciencedirect.com</span><span class="-me-1 flex h-full items-center rounded-full px-1 text-[#8F8F8F]">+11</span></span><span class="flex h-4 w-full items-center justify-between"><span class="max-w-full grow truncate overflow-hidden text-center">pmc.ncbi.nlm.nih.gov</span><span class="-me-1 flex h-full items-center rounded-full px-1 text-[#8F8F8F]">+11</span></span><span class="flex h-4 w-full items-center justify-between absolute"><span class="max-w-full grow truncate overflow-hidden text-center">mdpi.com</span><span class="-me-1 flex h-full items-center rounded-full px-1 text-[#8F8F8F]">+11</span></span></span>](https://pmc.ncbi.nlm.nih.gov/articles/PMC9179163/?utm_source=chatgpt.com)</span></span>.

<span class="relative -mx-px my-[-0.2rem] rounded px-px py-[0.2rem] transition-colors duration-100 ease-in-out">Des formulations utilisant **1 g/L de peptone** (souvent à base de tryptone) avec 20–30 g/L NaCl, glycerol et yeast extract assurent aussi une croissance stable et soutenue, dans le cadre de milieux optimisés pour la bioluminescence.</span>

#### Effet sur la bioluminescence

- <span class="relative -mx-px my-[-0.2rem] rounded px-px py-[0.2rem] transition-colors duration-100 ease-in-out">Un milieu complet contenant tryptone stimule la lumière : après 12 h, *P. phosphoreum* T3 atteint ~6,5×10⁷ RLU ; Q67 ~2,7×10⁶ RLU</span> <span class="" data-state="closed"><span class="ms-1 inline-flex max-w-full items-center relative top-[-0.094rem] animate-[show_150ms_ease-in]">[<span class="relative start-0 bottom-0 flex h-full w-full items-center"><span class="flex h-4 w-full items-center justify-between absolute"><span class="max-w-full grow truncate overflow-hidden text-center">journals.asm.org</span><span class="-me-1 flex h-full items-center rounded-full px-1 text-[#8F8F8F]">+7</span></span><span class="flex h-4 w-full items-center justify-between"><span class="max-w-full grow truncate overflow-hidden text-center">pmc.ncbi.nlm.nih.gov</span><span class="-me-1 flex h-full items-center rounded-full px-1 text-[#8F8F8F]">+7</span></span><span class="flex h-4 w-full items-center justify-between absolute"><span class="max-w-full grow truncate overflow-hidden text-center">mdpi.com</span><span class="-me-1 flex h-full items-center rounded-full px-1 text-[#8F8F8F]">+7</span></span></span>](https://pmc.ncbi.nlm.nih.gov/articles/PMC9179163/?utm_source=chatgpt.com)</span></span>.
- <span class="relative -mx-px my-[-0.2rem] rounded px-px py-[0.2rem] transition-colors duration-100 ease-in-out">Dans le milieu modifié dit “Boss medium” (contenu en peptone/tryptone), la luminescence est maximale à **pH 7,0**, avec **peptone 1 g/L**, **yeast extract 1 g/L**, **NaCl 20 g/L**, **glycerol 2,5 g/L** et atteint un signal RLU stable (~13 600 en continu pendant &gt;120 h)</span> <span class="" data-state="closed"><span class="ms-1 inline-flex max-w-full items-center relative top-[-0.094rem] animate-[show_150ms_ease-in]">[<span class="relative start-0 bottom-0 flex h-full w-full items-center"><span class="flex h-4 w-full items-center justify-between"><span class="max-w-full grow truncate overflow-hidden text-center">researchgate.net</span><span class="-me-1 flex h-full items-center rounded-full px-1 text-[#8F8F8F]">+1</span></span><span class="flex h-4 w-full items-center justify-between absolute"><span class="max-w-full grow truncate overflow-hidden text-center">mdpi.com</span><span class="-me-1 flex h-full items-center rounded-full px-1 text-[#8F8F8F]">+1</span></span></span>](https://www.researchgate.net/publication/45270098_Improved_detection_of_toxic_chemicals_by_Photobacterium_phosphoreum_using_modified_Boss_medium?utm_source=chatgpt.com)</span></span>.