Biosynthesis of 2-methylisoborneol is regulated by chromatic acclimation of Pseudanabaena

Published

Wednesday, September 25, 2024

Ming Su1,2,7,*, Jiao Fang1,8, Zeyu Jia1,3, Yuliang Su4, Yiping Zhu5, Bin Wu4, John C. Little6, Jianwei Yu1,2,7, Min Yang1,2,7

1. Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085.

2. National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085.

3. Yangtze Eco-Environment Engineering Research Center, China Three Gorges Corporation, Beijing, 100038.

4. Zhuhai Water Environment Holdings Group Ltd., Zhuhai, 519020.

5. Shanghai Chengtou Raw Water Co. Ltd., Beiai Rd. 1540, Shanghai, 200125.

6. Department of Civil and Environmental Engineering, Virginia Tech., Blacksburg, VA, 24061-0246.

7. University of Chinese Academy of Sciences, Beijing, 100049.

8. School of Civil Engineering, Chang’an University, Xi’an, 710054.

* Corresponding Author: Ming Su (mingsu@rcees.ac.cn)

Supplementarty Material

Figures and/or tables are provided below as the supplemenatary evidences to the main text.

Images of culture solution

Fig. 1 Pink color of Pseudanabaena (FACHB-1277) in decline phase
Fig. 2 Photo in the light color batch culture experiment

Relative abundances of pigments under different light color culture conditions

Four typical cyanobacterial photosynthetic pigments were identified according to their fluorescence excitation (Table 1).

Table 1 Fluorescence excitation and emission wavelength of typical photosynthetic pigments
Photosynthetic pigments excitation wavelength emission wavelength
Chlorophyll a (Chla) 427 nm 680 nm
phycoerythrin (PE) 488 nm 588 nm
phycocyanin (PC) 600 nm 660 nm
Allophycocyanin (APC) 633 nm 660 nm
Carotenoids 513 nm 556 nm

The relative abundances of each pigment were further estimated by the absorption spectrum of the culture solution under different light color conditions. In more detail, Chl a, PC, PE and carotenoids were identified and APC was not detected in the culture solutions according to Table 1, hence we regarded the amount of APC is ignorable. Subsequently, we identified the absorption spectrums of each pure pigment (Fig. 3), and linear models were constructed between the absorption spectrum of culture soloutions (\(Y_i\), \(i = (W, R, G, B)\)) and Chl a (\(p_1\)), PC (\(p_2\)), PE (\(p_3\)) and carotenoids (\(p_4\)) for different light color culture conditions Eq. 1, and the relative abundances of each pigments of culture solutions under white (\(\lambda_W\)), Red (\(\lambda_R\)), Green (\(\lambda_G\)), Blue (\(\lambda_B\)) light conditions were determined according to the least squares algorithm.

\[ Y_i=\lambda_{1i}p_1+\lambda_{2i}p_2+\lambda_{3i}p_3+\lambda_{4i}p_4 \tag{1}\]

Fig. 3 Relative absorption of photosynthetic pigments