Elucidating detoxification mechanisms of the phototoxic chlorophyll by aquatic microbes

2017 Fiscal Year Final Research Report

• Project/Area Number: 16K14813
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Ecology/Environment
• Research Institution: Fukui University of Technology
• Principal Investigator: Kashiyama Yuichiro 福井工業大学, 環境情報学部, 教授 (00611782)
• Co-Investigator(Kenkyū-buntansha): 谷藤 吾朗 独立行政法人国立科学博物館, 動物研究部, 研究員 (70438480) ; 中澤 昌美 大阪府立大学, 生命環境科学研究科, 助教 (90343417) ; 矢吹 彬憲 国立研究開発法人海洋研究開発機構, 海洋生物多様性研究分野, 研究員 (20711104) ; 横山 亜紀子 国立研究開発法人国立環境研究所, 地域環境研究センター, 特別研究員 (30466601)
• Project Period (FY): 2016-04-01 – 2018-03-31
• Keywords: chlorophylls / chlorophyll catabolism / algivorous protists

Outline of Final Research Achievements

We elucidated that CPE catabolism is ubiquitous chlorophyll degradation process in eukaryotes from extensive experiments and pigment analyses on two-membered cultures protistan predators and algal prey as well as unialgal cultures of microalgae; thus, the results showed that CPE catabolism is also common among many of algal lineages with the secondary plastids. We then carried out a comparative transcriptome analysis on a protistan predator that feeds on both cyanobacteria (performing CPE catabolism) and non-phototrophic bacteria and inferred changes in a gene expression profile responding upon predation of chlorophyll-containing cyanobacteria. Furthermore, we suggested by a reverse genetic approach, the RNAi knockdown experiments on Euglena gracilis, that a part of genes responsible for degradation of chlorophylls known among green plants are preserved and functioned in the secondary chloroplasts of euglenophytes algae.

Free Research Field

microbiology