Tengxin Cao , Ming Su , Yufan Ai , Ziyi Yang , Jinbo Zhao , Min Yang
{"title":"Green light suppresses cell growth but enhances photosynthetic rate and MIB biosynthesis in PE-containing Pseudanabaena","authors":"Tengxin Cao , Ming Su , Yufan Ai , Ziyi Yang , Jinbo Zhao , Min Yang","doi":"10.1016/j.watres.2025.123336","DOIUrl":null,"url":null,"abstract":"<div><div>2-Methylisoborneol (MIB) is a notorious musty odorant in drinking water systems, produced by cyanobacteria during the biosynthesis of photosynthetic pigments. This study investigated the physiological adaptation of <em>Pseudanabaena cinerea</em>, a phycoerythrin (PE)-containing and MIB-producing cyanobacterium, by inducing chromatic acclimation under different light color. Our findings revealed that red light enhanced growth rates by stimulating the tricarboxylic acid (TCA) cycle and associated metabolic processes, while green light significantly increased photosynthetic pigment content and electron transport efficiency. MIB yield correlated nonlinearly with chlorophyll <em>a</em> (Chl <em>a</em>) content, modeled by a logarithmic-linear equation (R<sup>2</sup> = 0.74, <em>p</em> < 0.01). This was supported by the strong correlation between <em>mic</em> and <em>chlG</em> gene expression at the RNA level (R<sup>2</sup> = 0.85, <em>p</em> < 0.01). The model showed that < 2 % of carbon flux is allocated to MIB biosynthesis compared to Chl <em>a</em> production, indicating that MIB biosynthesis is synergistic, not competitive, with photosynthetic pigment production. The red-shift in light spectra due to increased water turbidity observed in the field led to changes in photosynthetic pigments, which decreased MIB levels. This study improves our understanding of MIB-producing cyanobacteria under variable light conditions and offers insights for mitigating MIB occurrences in surface waters.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"277 ","pages":"Article 123336"},"PeriodicalIF":11.4000,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Water Research","FirstCategoryId":"93","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0043135425002490","RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENGINEERING, ENVIRONMENTAL","Score":null,"Total":0}
Green light suppresses cell growth but enhances photosynthetic rate and MIB biosynthesis in PE-containing Pseudanabaena
2-Methylisoborneol (MIB) is a notorious musty odorant in drinking water systems, produced by cyanobacteria during the biosynthesis of photosynthetic pigments. This study investigated the physiological adaptation of Pseudanabaena cinerea, a phycoerythrin (PE)-containing and MIB-producing cyanobacterium, by inducing chromatic acclimation under different light color. Our findings revealed that red light enhanced growth rates by stimulating the tricarboxylic acid (TCA) cycle and associated metabolic processes, while green light significantly increased photosynthetic pigment content and electron transport efficiency. MIB yield correlated nonlinearly with chlorophyll a (Chl a) content, modeled by a logarithmic-linear equation (R2 = 0.74, p < 0.01). This was supported by the strong correlation between mic and chlG gene expression at the RNA level (R2 = 0.85, p < 0.01). The model showed that < 2 % of carbon flux is allocated to MIB biosynthesis compared to Chl a production, indicating that MIB biosynthesis is synergistic, not competitive, with photosynthetic pigment production. The red-shift in light spectra due to increased water turbidity observed in the field led to changes in photosynthetic pigments, which decreased MIB levels. This study improves our understanding of MIB-producing cyanobacteria under variable light conditions and offers insights for mitigating MIB occurrences in surface waters.
期刊介绍:
Water Research, along with its open access companion journal Water Research X, serves as a platform for publishing original research papers covering various aspects of the science and technology related to the anthropogenic water cycle, water quality, and its management worldwide. The audience targeted by the journal comprises biologists, chemical engineers, chemists, civil engineers, environmental engineers, limnologists, and microbiologists. The scope of the journal include:
•Treatment processes for water and wastewaters (municipal, agricultural, industrial, and on-site treatment), including resource recovery and residuals management;
•Urban hydrology including sewer systems, stormwater management, and green infrastructure;
•Drinking water treatment and distribution;
•Potable and non-potable water reuse;
•Sanitation, public health, and risk assessment;
•Anaerobic digestion, solid and hazardous waste management, including source characterization and the effects and control of leachates and gaseous emissions;
•Contaminants (chemical, microbial, anthropogenic particles such as nanoparticles or microplastics) and related water quality sensing, monitoring, fate, and assessment;
•Anthropogenic impacts on inland, tidal, coastal and urban waters, focusing on surface and ground waters, and point and non-point sources of pollution;
•Environmental restoration, linked to surface water, groundwater and groundwater remediation;
•Analysis of the interfaces between sediments and water, and between water and atmosphere, focusing specifically on anthropogenic impacts;
•Mathematical modelling, systems analysis, machine learning, and beneficial use of big data related to the anthropogenic water cycle;
•Socio-economic, policy, and regulations studies.