Microbacterium diaminobutyricum sp. nov., isolated from Halimione portulacoides, which contains diaminobutyric acid in its cell wall, and emended description of the genus Microbacterium

Abstract

Three actinobacterial strains were isolated from roots of the salt-marsh plant Halimione portulacoides collected in Ria de Aveiro, Portugal. Molecular typing using enterobacterial repetitive intergenic consensus ERIC-PCR fingerprinting showed the strains to be highly similar. Phylogenetic analyses based on the 16S rRNA gene sequence and multilocus sequence analysis (MLSA) using gyrB, rpoB, recA and ppk and 16S rRNA genes sequences showed that the strains represented a member of the genus Microbacterium, with Microbacterium lacus DSM 18910T as the closest phylogenetic relative. DNA-DNA hybridization between strain RZ63T and its closest relative was below 70 %, supporting the hypothesis that it represented a distinct genomic species. Chemotaxonomic analyses of the novel strains and their DNA G+C contents confirmed their affiliation to the genus Microbacterium, however, the peptidoglycan of RZ63T contained diaminobutyric acid as the diagnostic diamino acid. In addition, physiological and fatty acid analyses revealed differences between these strains and their phylogenetic relatives, reinforcing their status as a distinct species. Based on the physiological, genetic and chemotaxonomic characterisation it is proposed that the strains studied represent a novel species of the genus Microbacterium for which the name Microbacterium diaminobutyricum sp. nov. is proposed (type strain RZ63T=DSM 27101T=CECT 8355T).

Transcriptional regulation of ectoine catabolism in response to multiple metabolic and environmental cues

“…Apart from the high affinity of EnuR for N-(a)-ADABA, this compound has the additional advantage of being a specific ectoine-derived metabolite (Fig. 1), whereas DABA occurs also as an intermediate in other metabolic and biosynthetic processes in microorganisms (Ikai and Yamamoto, 1997;Du et al, 2013;Fidalgo et al, 2016), including the biosynthesis of ectoine (Ono et al, 1999) (Fig. 1).…”

“…Since DABA is also produced in microbial pathways not involved in ectoine catabolism (Ikai and Yamamoto, 1997;Du et al, 2013;Fidalgo et al, 2016), we set out to genetically and biochemically define the physiologically most relevant system-specific inducer for EnuR. We identify it here as N-(a)-ADABA, a highly specific intermediate of ectoine catabolism (Schwibbert et al, 2011;Schulz et al, 2017) (Fig.…”

Design of a bio-conditioner prototype for the treatment of degraded soils: biomass production and lignite formulation for Microbacterium sp. CSB3

“…Microbacterium sp. is an aerobic bacterial genus, therefore it requires high oxygen availability [19]. There are few reports of fermentative processes with this genus for biomass production purposes; however, Thys et al [20] described the production of proteases with Microbacterium sp.…”

Microbacterium protaetiae sp. nov., isolated from gut of larva of Protaetia brevitarsis seulensis

“…The genus Microbacterium was first described by Orla-Jensen [1], and the description was later emended several times [2–5] mainly due to the diversity of peptidoglycan structure. The genus was characterized as Gram-stain-positive, asporogenous and rod shaped with optimum growth observed at 20–30 °C [6].…”