Cyanobacterial pattern formations
Scientific studies
2005 - present
Cyanobacteria show a great diversity in their cellular and colony morphology. Initially, we studied semiregularly patterned 'heterocyst' differentiation in the filamentous species, Anabaena sp. PCC 7120. Anabaena differentiates heterocyst that is specific for nitrogen fixation at about every 10 cells in the absence of nitrogen source in media. By combinatorial approach of time-lapse single cell monitoring and mathematical simulations, we provided detailed cell lineage profile of non-pre-deterministic heterocyst formation dynamics (Asai et al. PLoS ONE, 2012) and its theoretical property (Ishihara et al. J. theor. Biol. 2014).
Then, Hideo started biomedia art project using cyanobacterial isolates from the wild. Some of them showed striking morphological patterns in their colony formations upon a series of experiments for the arts. Thus, as a biproduct of the art projects, Hideo started scientific research on cyanobacterial colony pattern formations. Especially, we are studying on vortice or comet-like colony pattern formations in Geitlerinema sp., Pseudanabaena sp. and Leptolyngbia sp. It should be noted that our morphological study follows the art, different from a stereotype that scientifically known phenomena are applied to make some arts. We will update our findings after publications in preparation.

Research articles
Kazuma Toida, Wakana Kushida, Hiroki Yamamoto, Kyoka Yamamoto, Kazuma Uesaka, Kunio Ihara, Yuichi Fujita, Hideo Iwasaki (2022) "The dgc2 gene encoding di-guanylate cyclase suppresses both motility and biofilm formation in the filamentous cyanobacterium Leptolyngbya boryana" preprint, BioRxiv, doi:
Shiryu Kirie, Hideo Iwasaki, Koji Noshita, Hiroyoshi Iwata (2020) "A theoretical morphological model for quantitative description of the three-dimensional floral morphology in water lily (Nymphaea)"
PLOS ONE 15(10) e0239781-e0239781  doi:
Shumpei Hisamoto, Natsumi Hosaka, Yuka Matsunami, Hideo Iwasaki (2020) "Route reassessment by transporter ants improves speed and directional accuracy of cooperative transport in Formica japonica" Journal of Ethology 38(1) 107-116
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