This is a list of the culture collection of Cyanidiales and other microalgae isolated from different geothermal areas in the West Pacific Island Chain, the first chain. During our experiments, we frequently encountered mixed contamination, which resulted from the combination of two different algal species or strains instead of fungi and bacteria. One of the reasons for this issue may be the adhesion of two mixed strains using only a plate streaking isolation procedure (i.e., the initial isolation). To address this, we purified the culture strains from the initial isolation by using a plate streaking isolation followed by a serial dilution (i.e., the first-time purification). After purification, we picked a single colony and transferred it to sloped agar in a test tube for long-term culture storage. After every physiological experiment, we washed the purified strain from the test tube and repeated the above-mentioned isolation process (i.e., the second-time purification, and so on). We followed the same procedure for those obtained from other culture centers. Additionally, after each purification step, including the initial isolation and first-time purification, we molecularly barcoded the identity of the strain using rbcL to ensure that the target strain was not contaminated. For the purification procedure described above, we conducted the purification process for each strain at a time in a laminar flow chamber treated with 70% EtOH and overnight UV light (i.e., one working day per strain). By doing so, we ensured that the cultured strain was pure in terms of a single algal species (i.e., isogenic strain) without any contamination of other algae, fungi, and bacteria. 

I. Isolated cyanidia strains in the THAL culture collection

• Galdieria partita
  Strain: THAL001
  Strain purity: The first time purification
  Site: DiReGu, Yangmingshan National Park, Taiwan
  Microhabitat: stream (Temp = no measurement; pH = no measurement)

• Galdieria sulphuraria
  Strain: THAL003
  Strain purity: The initial isolation
  Site: DiReGu, Yangmingshan National Park, Taiwan
  Microhabitat: stream (Temp = no measurement; pH = no measurement)

• Galdieria partita
  Strain: THAL010
  Strain purity: The initial isolation
  Site: MaCao, Yangmingshan National Park, Taiwan
  Microhabitat: stream (Temp = 38.7℃; pH = 3.82)

• Galdieria sp.
  Strain: THAL011
  Strain purity: The first time purification
  Site: Tengchong , China
  Microhabitat: endolithic (Temp = 45.2℃; pH = 2.12)

• Galdieria sp.
  Strain: THAL012
  Strain purity: The first time purification
  Site: Tengchong , China
  Microhabitat: endolithic (Temp = 45.2℃; pH = 2.12)

• Galdieria partita
  Strain: THAL017
  Strain purity: The initial isolation
  Site: Pinus, Indonesia
  Microhabitat: stream (Temp = 37.0℃; pH = 2.65)

• Galdieria partita
  Strain: THAL018
  Strain purity: The initial isolation
  Site: Bukit Kaish, Indonesia
  Microhabitat: endolithic (Temp = 26.7℃; pH = 0.4)

• Galdieria partita
  Strain: THAL019
  Strain purity: The initial isolation
  Site: Zano Pasuh, Indonesia
  Microhabitat: clay sulfur deposit soil (Temp = 24.8℃; pH = 0.4)

• Galdieria partita
  Strain: THAL022
  Strain purity: The initial isolation
  Site: Valencia, Philippines
  Microhabitat: hypolithic (Temp = 39.0℃; pH = 0.4)

• Galdieria partita
  Strain: THAL023
  Strain purity: The first time purification
  Site: Fukenoyu, Japan
  Microhabitat: river (Temp = 35.0℃; pH = 1.6)

• Galdieria partita
  Strain: THAL024
  Strain purity: The initial isolation
  Site: Fukenoyu, Japan
  Microhabitat: river (Temp = 35.0℃; pH = 1.6)

• Galdieria partita
  Strain: THAL025
  Strain purity: The first time purification
  Site: Dauwin, Philippines
  Microhabitat: stream (Temp = 48.0 ℃; pH = 1.97)

• Galdieria partita
  Strain: THAL028
  Strain purity: The initial isolation
  Site: Danav Linow, Indonesia
  Microhabitat: Epilithic clay sulfur deposit (Temp = 29.5℃; pH = 0.4)

• Galdieria partita
  Strain: THAL029
  Strain purity: The initial isolation
  Site: Zano Pasuh, Indonesia
  Microhabitat: Endolithic sulfur crystal rock (Temp = 26.6℃; pH = 2.8)

• Galdieria sulphuraria
  Strain: THAL030
  Strain purity: The first time purification
  Site: GengZiPing, Yangmingshan National Park, Taiwan
  Microhabitat: stream (Temp = 45.5℃; pH = 2.5)

• Galdieria partita
  Strain: THAL033
  Strain purity: The initial isolation
  Site: GengZiPing, Yangmingshan National Park, Taiwan
  Microhabitat: stream (Temp = 39.0℃; pH = 2.57)

• Galdieria partita
  Strain: THAL034
  Strain purity: The initial isolation
  Site: SiHuangPing, Yangmingshan National Park, Taiwan
  Microhabitat: epilithic (Temp = no measurement; pH = no measurement)

• Galdieria partita
  Strain: THAL036
  Strain purity: The first time purification
  Site: DaYouKen, Yangmingshan National Park, Taiwan
  Microhabitat: stream (Temp = 43.4℃; pH = 2.27)

• Galdieria partita
  Strain: THAL043
  Strain purity: The first time purification
  Site: DaYouKen, Yangmingshan National Park, Taiwan
  Microhabitat: stream (Temp = 46.0-48.0℃; pH = 2.15)

• Galdieria partita
  Strain: THAL046
  Strain purity: The initial isolation
  Site: Camiguium, Philippines
  Microhabitat: stone (Temp = 40.0℃; pH = 2.8)

• Galdieria partita
  Strain: THAL047
  Strain purity: The initial isolation
  Site: Valencia, Philippines
  Microhabitat: hypolithic (Temp = 26.6℃; pH = 2.8)

• Galdieria partita
  Strain: THAL052
  Strain purity: The initial isolation
  Site: Umi Jigoku, Japan
  Microhabitat: pool (Temp = 45.0℃; pH = 3)

• Galdieria partita
  Strain: THAL056
  Strain purity: The initial isolation
  Site: Nishinokawara, Kusatsu, Japan
  Microhabitat: pool (Temp = 45.1℃; pH = 1.87)

• Galdieria daedala
  Strain: THAL058
  Strain purity: The first time purification
  Site: Jigokunma, Sukayu, Aomori, Japan
  Microhabitat: stream (Temp = 42.1°C; pH = 1.99)

• Galdieria partita
  Strain: THAL059
  Strain purity: The initial isolation
  Site: Sukayu, Aomori, Japan
  Microhabitat: epilith (Temp = 33.1°C; pH = 0.4)

• Galdieria partita
  Strain: THAL060
  Strain purity: The initial isolation
  Site: Sainokawara, Sukayu, Aomori, Japan
  Microhabitat: epilith (Temp = 42.2°C; pH = 0.4)

• Galdieria partita
  Strain: THAL064
  Strain purity: The initial isolation
  Site: Nishinokawara, Kusatsu, Japan
  Microhabitat: pool (Temp = 45.1℃; pH = 1.87)

• Galdieria partita
  Strain: THAL065
  Strain purity: The initial isolation
  Site: Sessyogara, Kusatsu, Japan
  Microhabitat: epilithic (Temp = 23.3℃; pH = 0.4)

• Cyanidiococcus yangmingshanensis
  Strain: THAL066, NIES-4390
  Strain purity: The first time purification
  Site: GenZiPeng, Yangmingshan National Park, Taiwan
  Microhabitat: air (Temp = no measurement; pH = no measurement)

• Galdieria partita
  Strain: THAL069
  Strain purity: The first time purification
  Site: GengZiPing, Yangmingshan National Park, Taiwan
  Microhabitat: soil with crystallized sulfate (Temp = 16.8°C; pH < 0.4)

• Galdieria cf. sulphuraria
  Strain: THAL079
  Strain purity: The first time purification
  Site: Rotorua Hell's Gate, New Zealand
  Microhabitat: air (Temp = no measurement; pH = no measurement)

• Cyanidiococcus cf. yangmingshanensis
  Strain: THAL093
  Strain purity: The first time purification
  Site: GengZiPing, Yangmingshan National Park, Taiwan
  Microhabitat: stream (Temp = 41.8℃; pH = 1.92)

• Cyanidiococcus cf. yangmingshanensis
  Strain: THAL094
  Strain purity: The first time purification
  Site: Yunokawa onsen ashiyu, Hakodate, Hokkaido, Japan
  Microhabitat: stream (Temp = 46.0℃; pH = 1.72)

• Cyanidiococcus cf. yangmingshanensis
  Strain: THAL095
  Strain purity: The first time purification
  Site: GengZiPing, Yangmingshan National Park, Taiwan
  Microhabitat: stream (Temp = 41.8℃; pH = 1.92)

• Cyanidiococcus cf. yangmingshanensis
  Strain: THAL096
  Strain purity: The first time purification
  Site: Buckit Kasih, Manado, Indonesia
  Microhabitat: endolith (Temp = 31.3°C; pH = 0.4)

• Cyanidiococcus cf. yangmingshanensis
  Strain: THAL097
  Strain purity: The first time purification
  Site: Teshikaga, Hokkaido, Japan
  Microhabitat: stream (Temp = 40.0℃; pH = 2)

• Cyanidiufrigus pintoensis
  Strain: THAL103
  Strain purity: The third time purification with fungi contamination
  Site: GengZiPing, Yangmingshan National Park, Taiwan
  Microhabitat: air (Temp = no measurement; pH = no measurement)

• Galdieria daedala
  Strain: THAL105
  Strain purity: The first time purification
  Site: Mount Iwo, Akan Volcanic Complex, Hokkado, Japan
  Microhabitat: ditch (Temp = ca. 40℃; pH = 2.0)

II. Strains obtained from other culture centers

• Cyanidiococcus yangmingshanensis
  Strain: NIES2137
  Strain purity: The first time purification
  Site: Nikko-Yumoto Hot spring, Nikko Tochigi, Japan

• Galdieria yellowstonensis
  Strain: SAG107.79
  Strain purity: The first time purification
  Site: Lemonade springs, California, Sonoma Co, United States

• Galdieria javensis
  Strain: 074G
  Strain purity: The first time purification
  Site: Java, Mt. Lawu fumaroles, Indonesia

• Cyanidium caldarium
  Strain: NIES551
  Strain purity: The first time purification
  Site: UNKNOWN

• Galdieria phlegrea
  Strain: CCCryo128-00
  Strain purity: The first time purification
  Site: Soos, near Skalná Hájek, Districk of Cheb, Region of Karlovacky, Czech Republic

• Cyanidioschyzon merolae
  Strain: 10D (NIES3377)
  Strain purity: the first time purification
  Site: A geothermal site at Sardegna in Italy

 Relevant Publications

• Huang TY, Yoon HS, Chiang YR, Fu HY, Watanabe T, Gerung GS, Geraldino PJL, Liu SL*. 2024. Diversity in Cyanidiophyceae: Cyanidiofrigus pintoensis gen. et sp. nov. within polyextremophilic red algae (Rhodophyta). Phycologia 63: 245-259. (THAL103)

• Park SI, Cho CH, Ciniglia C, Huang TY, Liu SL, Bustamante DE, Calderon MS, Mansilla, McDermott T, Andersen RA, Yoon HS*. 2023. Revised classification of the Cyanidiophyceae based on plastid genome data with descriptions of the Cavernulicolales ord. nov. and Galdieriales ord. nov. Journal of Phycology 59: 444-466. (THAL103)

• Choa YL, Tzou YM, Wang CC, Lee YC, Hsu LC, Liu SL, Assakinah A, Chen YH, Than NAT, Liu YT*, Rinklebee J. 2023. Removal and concurrent reduction of Cr(VI) by thermoacidophilic Cyanidiales: a novel extreme biomaterial enlightened for acidic and neutral conditions. Journal of Hazardous Materials 445: 130334. (10D, THAL066, NIES551, NIES3377)

• Cho YL, Lee YC, Hsu LC, Wang CC, Chen PC, Liu SL, Teah HY, Liu YT*, Tzou YM*. 2020. Molecular mechanisms for Pb removal by Cyanidiales: a potential biomaterial applied in thermo-acidic conditions. Chemical Engineering Journal 401: 125828. (THAL066, NIES551, NIES3377)

• Liu SL, Chiang YR, Yoon HS, Fu HY*. 2020. Comparative genome analysis reveals Cyanidiococcus gen. nov., a new extremophilic algal genus sister to Cyanidioschyzon (Cyanidioschyzonaceae, Rhodophyta). Journal of Phycology 56: 1428-1442. (THAL066; NIES-4390)

• Fu HY, Liu SL, Chiang YR. 2020. Biosynthesis of ascorbate acid as a glucose-induced photoprotective process in the extremophilic red alga Galdieria partita. Frontiers in Microbiology 10: 3005. (THAL043)

• Hsieh CJ, Zhan SH, Liao CP, Tang SL, Wang LC, Watanabe T, Geraldino PJ, Liu SL. 2018. The effects of contemporary selection and dispersal limitation on the community assembly of acidophilic microalgae. Journal of Phycology 54: 720-733. (Environmental Sample Collection)

• Hsieh CJ, Zhan SH, Lin YC, Tang SL, Liu SL. 2015. Analysis of rbcL sequences reveals the global biodiversity, community structure, and biogeographical pattern of thermoacidophilic red algae (Cyanidiales). Journal of Phycology 51: 682-694.  (Environmental Sample Collection)