Lichenicoccus roseus gen. nov., sp. nov., the first bacteriochlorophyll a-containing, psychrophilic and acidophilic Acetobacteraceae bacteriobiont of lichen Cladonia species

Abstract

Gram-negative, aerobic, chemo-organotrophic and bacteriochlorophyll a-containing bacterial strains, KEBCLARHB70RT, KAMCLST3051 and KAMCLST3152, were isolated from the thalli of Cladonia arbuscula and Cladonia stellaris lichens. Cells from the strains were coccoid and reproduced by binary division. They were motile at the early stages of growth and utilized sugars and alcohols. All strains were psychrophilic and acidophilic, capable of growth between pH 3.5 and 7.5 (optimum, pH 5.5), and at 4–30 °C (optimum, 10–15 °C). The major fatty acids were C18 : 1 ω7c and C18 : 0; the lipids were phosphatidylcholines, phosphatidylethanolamines, phosphatidic acids, phosphatidylglycerol, glycolipids, diphosphatidylglycerol and polar lipids with an unknown structure. The quinone was Q-10. The DNA G+C content was 67.8 mol%. Comparative 16S rRNA gene analysis together with other data, supported that the strains, KEBCLARHB70RT, KAMCLST3051 and KAMCLST3152 belonged to the same species. Whole genome analysis of the strain KEBCLARHB70RT and average amino acid identity values confirmed its distinctive phylogenetic position within the family Acetobacteraceae . Phenotypic, ecological and genomic characteristics distinguished strains KEBCLARHB70RT, KAMCLST3051 and KAMCLST3152 from all genera in the family Acetobacteraceae . Therefore, we propose a novel genus and a novel species, Lichenicoccus roseus gen. nov., sp. nov., for these novel Acetobacteraceae members. Strain KEBCLARHB70RT (=KCTC 72321T=VKM B-3305T) has been designated as the type strain.

The phylogeny of Acetobacteraceae : photosynthetic traits and deranged respiratory enzymes

“…Table 2 ), while about one-half of the other MAGs cluster with established photosynthetic Acetobacteraceae such as Rhodopila (clades a, b, and LMUY01, Table 2 ). Conversely, two non-photosynthetic Antarctic MAGs (clade d, Table 2 ) cluster within the group of Lichenicoccus ( 36 ), which includes the recently reported ( 51 ) Acetobacteraceae KSS8 and KSS12 ( Fig. 1A and 2A ).…”

“…S1A and D; cf. references ( 1 , 2 , 4 , 5 , 36 , 41 )]. This compact phylogenetic pattern implies that the fundamental contours of the acetous clade can be defined by a few representatives of the major subclades with acetous character, for example, Acetobacter and Gluconobacter , as shown in Fig.…”

“…1A , cf. references ( 1 – 5 , 36 )]. However, this common branching pattern depends upon the phylogenetic marker and taxonomic sampling used to reconstruct the trees.…”

“…This is a novel concept in the phylogeny of Acetobacteraceae [cf. references ( 2 ) and ( 4 , 36 )], which deserved further detailed analysis.…”

“…Phylogenetic trees were initially reconstructed using the neighbor joining (NJ) approach using the MEGA5 program (usually with the JTT model and 500 bootstraps) to orient the phylogenetic analysis. Subsequently, robust phylogenies were obtained in most cases with maximum likelihood (ML) inference ( 19 , 34 – 36 ) using the program IQ-Tree as described recently ( 34 ) and methodological details that are presented in the figure legend. In some cases, Bayesian inference was additionally used ( 35 ).…”