Evidence map›Paper›PMID 36650459›Full record

ArticleBMC microbiology2023

Cryopreservation of two species of the multicellular volvocine green algal genus Astrephomene.

Hisayoshi Nozaki, Fumi Mori, Yoko Tanaka, Ryo Matsuzaki, Shota Yamashita, Haruyo Yamaguchi, Masanobu Kawachi

Abstract read
In one paragraph

Article in BMC microbiology, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0citing papers in PubMed
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1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

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3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

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4 · The record

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PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors.

Hisayoshi NozakiBiodiversity Division, National Institute for Environmental Studies, Tsukuba, Ibaraki, 305-8506, Japan. hisayoshi.nozaki@gmail.com.
Fumi MoriBiodiversity Division, National Institute for Environmental Studies, Tsukuba, Ibaraki, 305-8506, Japan.
Yoko TanakaBiodiversity Division, National Institute for Environmental Studies, Tsukuba, Ibaraki, 305-8506, Japan.
Ryo MatsuzakiBiodiversity Division, National Institute for Environmental Studies, Tsukuba, Ibaraki, 305-8506, Japan.
Shota YamashitaDepartment of Biological Sciences, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan.
Haruyo YamaguchiBiodiversity Division, National Institute for Environmental Studies, Tsukuba, Ibaraki, 305-8506, Japan.
Masanobu KawachiBiodiversity Division, National Institute for Environmental Studies, Tsukuba, Ibaraki, 305-8506, Japan.

Funding

MEXT/ JSPS KAKENHI 20H03299The Institute for Fermentation, Osaka (IFO) G-2022-1-004
6 · The paper itself

Abstract

backgroundAstrephomene is an interesting green algal genus that, together with Volvox, shows convergent evolution of spheroidal multicellular bodies with somatic cells of the colonial or multicellular volvocine lineage. A recent whole-genome analysis of A. gubernaculifera resolved the molecular-genetic basis of such convergent evolution, and two species of Astrephomene were described. However, maintenance of culture strains of Astrephomene requires rapid inoculation of living cultures, and cryopreserved culture strains have not been established in public culture collections.

resultsTo establish cryopreserved culture strains of two species of Astrephomene, conditions for cryopreservation of the two species were investigated using immature and mature vegetative colonies and two cryoprotectants: N,N-dimethylformamide (DMF) and hydroxyacetone (HA). Rates of cell survival of the A. gubernaculifera or A. perforata strain after two-step cooling and freezing in liquid nitrogen were compared between different concentrations (3 and 6%) of DMF and HA and two types of colonies: immature colonies (small colonies newly released from the parent) and mature colonies (large colonies just before daughter colony formation). The highest rate of survival [11 ± 13% (0.36-33%) by the most probable number (MPN) method] of A. gubernaculifera strain NIES-4017 (established in 2014) was obtained when culture samples of immature colonies were subjected to cryogenic treatment with 6% DMF. In contrast, culture samples of mature colonies subjected to 3% HA cryogenic treatment showed the highest "MPN survival" [5.5 ± 5.9% (0.12-12%)] in A. perforata. Using the optimized cryopreservation conditions for each species, survival after freezing in liquid nitrogen was examined for six other strains of A. gubernaculifera (established from 1962 to 1981) and another A. perforata strain maintained in the Microbial Culture Collection at the National Institute for Environmental Studies (MCC-NIES). We obtained ≥0.1% MPN survival of the A. perforata strain. However, only two of the six strains of A. gubernaculifera showed ≥0.1% MPN survival. By using the optimal cryopreserved conditions obtained for each species, five cryopreserved strains of two species of Astrephomene were established and deposited in the MCC-NIES.

conclusionsThe optimal cryopreservation conditions differed between the two species of Astrephomene. Cryopreservation of long-term-maintained strains of A. gubernaculifera may be difficult; further studies of cryopreservation of these strains are needed.

Indexed as

ChlorophytaCryopreservationDimethylformamideFreezingDimethylformamideAsexual cycle, Astrephomene, Cryopreservation, Cryoprotectant, Culture collection, Volvocine green algae

Identifiers

PMID36650459
PMCPMC9847204

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.