Interplay between the microalgae Micrasterias radians and its symbiont Dyadobacter sp. HH091

Abstract

Based on previous research, related to detailed insight into mutualistic collaboration of microalga and its microbiome, we established an artificial plant-bacteria system of the microalga Micrasterias radians MZCH 672 and the bacterial isolate Dyadobacter sp. HH091. The bacteria, affiliated with the phylum Bacteroidota, strongly stimulated growth of the microalga when it was added to axenic algal cultures. For further advances, we studied the isolate HH091 and its interaction with the microalga M. radians using transcriptome and extensive genome analyses. The genome of HH091 contains predicted polysaccharide utilizing gene clusters co-working with the type IX secretion system (T9SS) and conceivably involved in the algae-bacteria liaison. Here, we focus on characterizing the mechanism of T9SS, implementing the attachment and invasion of microalga by Dyadobacter sp. HH091. Omics analysis exposed T9SS genes: gldK, gldL, gldM, gldN, sprA, sprE, sprF, sprT, porU and porV. Besides, gld genes not considered as the T9SS components but required for gliding motility and protein secretion (gldA, gldB, gldD, gldF, gldG, gldH, gldI, gldJ), were also identified at this analysis. A first model of T9SS apparatus of Dyadobacter was proposed in a course of this research. Using the combination of fluorescence labeling of Dyadobacter sp. HH091, we examined the bacterial colonisation and penetration into the cell wall of the algal host M. radians MZCH 672.

Effect of Abscisic Acid on Growth, Fatty Acid Profile, and Pigment Composition of the Chlorophyte Chlorella (Chromochloris) zofingiensis and Its Co-Culture Microbiome

“…Simultaneously, the increase of ABA concentration in cultures suppressed the relative abundance of genus Bradyrhizobium , which is known as a natural producer of various phytohormones in the rhizosphere and is capable of inducing an immunity response in plants to protect them from phytopathogens [ 100 , 101 ]. The authors of the current study also noticed the microbiomes from cultures treated with the minimal and maximal concentrations of ABA (1 and 50 μM, respectively) had high relative abundances of PGPB genera, such as Paenibacillus , Dyadobacter, and Brevibacillus , which might increase macronutrient availability and are important elements of host–microbial interactions in plants–rhizosphere and microalgae–phycosphere systems [ 102 , 103 , 104 ]. On the other hand, the middle range concentrations of ABA (5 and 10 μM) resulted in stimulating the growth of the genera, some of which are known to accompany microalgal cultures in the photobioreactor systems and provide microalgae with organic substrates or act as parasitic organisms [ 48 , 105 ].…”

Cutting through host autofluorescence: fluorescence lifetime imaging microscopy for visualising intracellular bacteria in Symbiodiniaceae

“…Various sample preparation approaches such as exposure of cells to sodium borohydride ( Castillo-Medina et al ., 2011 ), high light ( Webster et al ., 2001 ; Maire et al ., 2021 ), combined hydrogen peroxide and light ( Yakubovskaya et al ., 2019 ), copper sulfate and ethanol ( Cohen et al , 2021 ), fluorescence lifetime gating ( Kodama, 2016 ), TrueVIEW quenching kit ( Astafyeva et al ., 2022b ) and post image processing using deep learning tools ( Jiang et al ., 2022 ) are used for reduction of background autofluorescence. Maire et al .…”

Recent advances and fundamentals of microalgae cultivation technology

“…[53,145] Apparently, the microalgae growth in the cocultures with Dyadobacter was increased. [53,146] Likewise, in the marine bloom environment, population changes from diatom Skeletonema sp. to microalgae Phaeocystis sp.…”

“…[ 53,145 ] Apparently, the microalgae growth in the cocultures with Dyadobacter was increased. [ 53,146 ]…”