Paenibacillus taiwanensis sp. nov., isolated from soil in Taiwan

Characterization and in-depth genome analysis of a halotolerant probiotic bacterium Paenibacillus sp. S-12, a multifarious bacterium isolated from Rauvolfia serpentina

BACKGROUND

Members of Paenibacillus genus from diverse habitats have attracted great attention due to their multifarious properties. Considering that members of this genus are mostly free-living in soil, we characterized the genome of a halotolerant environmental isolate belonging to the genus Paenibacillus. The genome mining unravelled the presence of CAZymes, probiotic, and stress-protected genes that suggested strain S-12 for industrial and agricultural purposes.

RESULTS

Molecular identification by 16 S rRNA gene sequencing showed its closest match to other Paenibacillus species. The complete genome size of S-12 was 5.69 Mb, with a GC-content 46.5%. The genome analysis of S-12 unravelled the presence of an open reading frame (ORF) encoding the functions related to environmental stress tolerance, adhesion processes, multidrug efflux systems, and heavy metal resistance. Genome annotation identified the various genes for chemotaxis, flagellar motility, and biofilm production, illustrating its strong colonization ability.

CONCLUSION

The current findings provides the in-depth investigation of a probiotic Paenibacillus bacterium that possessed various genome features that enable the bacterium to survive under diverse conditions. The strain shows the strong ability for probiotic application purposes.

Paenibacillus arenosi sp. nov., a siderophore-producing bacterium isolated from coastal sediment

In this study, strain CAU 1523^T, a novel Gram-positive-positive bacterium isolated from marine sediment collected from the coast of Busan, Republic of Korea, was characterized using a polyphasic taxonomic approach. This strain showed growth at a temperature range of 20-37 °C (optimum, 30 °C), a pH range of 6.5-9.5 (optimum, 7.5), and in the presence of 0-3% (w/v) NaCl (optimum, 1%). Phylogenetic analysis based on 16S rRNA gene sequencing and 92 concatenated core genes indicated that CAU 1523^T belonged to the genus Paenibacillus, sharing the highest sequence similarity with P. assamensis JCM 13186^T (98.0%). CAU 1523^T was differentiated from other Paenibacillus species by average nucleotide identity, average amino acid identity, and digital DNA-DNA hybridization values, using cut-off values of 95-96%, 90%, and 70%, respectively, for closely related strains. The genome of CAU 1523^T possessed various biosynthetic gene clusters, one of which encoded a putative siderophore-interacting protein. Siderophore production by the isolate was confirmed using the qualitative chrome azurol sulfonate (CAS) agar assay. Based on its phylogenetic and physiological characteristics, strain CAU 1523^T represents a novel, siderophore-producing species within the genus Paenibacillus, for which the name Paenibacillus arenosi sp. nov. is proposed, with the type strain CAU 1523^T (= KCTC 43108^T = MCCC 1K04063^T).

Role of heavy metal tolerant rhizosphere bacteria in the phytoremediation of Cu and Pb using Eichhornia crassipes (Mart.) Solms

The role of multi-heavy metal tolerant bacteria isolated from the rhizosphere of Eichhornia crassipes in the phytoremediation of Cu and Pb under laboratory conditions was investigated. The heavy metal tolerant rhizosphere bacteria were identified as Bacillus cereus, Paenibacillus alvei, Aeromonas caviae, Paenibacillus taiwanensis, and Achromobacter spanius. Results showed a significant variation in wet weight, Heterotrophic Plate Count (HPC) of the rhizosphere, HPC of water, removal and uptake of Cu and Pb by E. crassipes, either alone or in association with the rhizosphere bacteria. The removal of Cu by E. crassipes in different experimental conditions showed that OTC (Oxytetracycline) untreated E. crassipes with rhizosphere bacteria has maximum removal with 95%, followed by E. crassipes alone with 84%. The OTC treated E. crassipes with rhizosphere bacteria could remove 81% of Cu. The maximum Pb removal efficiency of 93.4% was shown by OTC untreated E. crassipes with rhizosphere bacteria, followed by E. crassipes alone with 86.8%. The OTC treated E. crassipes with rhizosphere bacteria showed the least removal efficiency with 82.32%. The translocation factor (TF) values for Cu and Pb were lower than 1 indicated that the absorption was mainly accomplished in the roots of E. crassipes. The order of accumulation of Cu and Pb in E. crassipes was noted as root > leaf > petiole.

Whole-genome sequence-based analysis of the Paenibacillus aquistagni strain DK1, a polyethylene-degrading bacterium isolated from landfill

Polyethylene-degrading bacteria have been emerging as a rational and safe alternative in bioremediation strategies. In this context, some Paenibacillus species produce enzymes involved in the biodegradation of pollutants. Among the enzymes involved in the biodegradation of polyethylene, the alkane hydroxylases, encoded by alkB homologous genes, play a key role in this process. Therefore, this study aimed to identify and perform a genomic investigation of the first polyethylene-degrading Paenibacillus sp. strain, named DK1. The whole-genome sequence-based analysis revealed that the DK1 strain belonged to the species Paenibacillus aquistagni and shared a total of 4327 CDSs with P. aquistagni strain 11. On the other hand, a comparison of the gene clusters showed that DK1 strain harbored a genetic context surrounding the alkB-like gene similar to that found in Pseudomonas sp. strains. The percentage of similarity ranged from 47.88 to 99.76% among all complete amino acid sequences of AlkB-like proteins analyzed. Nevertheless, the predicted amino acid sequences of AlkB-like contained typical structural motifs of alkane hydroxylases, such as His boxes and the HYG motif. These findings associated with the previously reported phenotypic results highlighted the potential of P. aquistagni strain DK1 to biodegrade polyethylene. Therefore, further studies focusing on the biochemical and structural properties of the AlkB-like protein from Paenibacillus may also contribute to the development of sustainable bioremediation strategies.

Comparative genomic analysis of Paenibacillus sp. SSG-1 and its closely related strains reveals the effect of glycometabolism on environmental adaptation

The extensive environmental adaptability of the genus Paenibacillus is related to the enormous diversity of its gene repertoires. Paenibacillus sp. SSG-1 has previously been reported, and its agar-degradation trait has attracted our attention. Here, the genome sequence of Paenibacillus sp. SSG-1, together with 76 previously sequenced strains, was comparatively studied. The results show that the pan-genome of Paenibacillus is open and indicate that the current taxonomy of this genus is incorrect. The incessant flux of gene repertoires resulting from the processes of gain and loss largely contributed to the difference in genomic content and genome size in Paenibacillus. Furthermore, a large number of genes gained are associated with carbohydrate transport and metabolism. It indicates that the evolution of glycometabolism is a key factor for the environmental adaptability of Paenibacillus species. Interestingly, through horizontal gene transfer, Paenibacillus sp. SSG-1 acquired an approximately 150 kb DNA fragment and shows an agar-degrading characteristic distinct from most other non-marine bacteria. This region may be transported in bacteria as a complete unit responsible for agar degradation. Taken together, these results provide insights into the evolutionary pattern of Paenibacillus and have implications for studies on the taxonomy and functional genomics of this genus.

Paenibacillus aquistagni sp. nov., isolated from an artificial lake accumulating industrial wastewater

Strain 11^T was isolated from water of an artificial lake accumulating industrial wastewater on the outskirts of Celje, Slovenia. Phenotypic characterisation showed strain 11^T to be a Gram-stain positive, spore forming bacterium. The 16S rRNA gene sequence identified strain 11^T as a member of the genus Paenibacillus, closely related to Paenibacillus alvei (96.2%). Genomic similarity with P. alvei 29^T was 73.1% (gANI), 70.2% (ANIb), 86.7% (ANIm) and 21.7 ± 2.3% (GGDC). The DNA G+C content of strain 11^T was determined to be 47.5%. The predominant menaquinone of strain 11^T was identified as MK-7 and the major fatty acid as anteiso-C_15:0. The peptidoglycan was found to contain meso-diaminopimelic acid. In contrast to its close relatives P. alvei DSM 29^T, Paenibacillus apiarius DSM 5581^T and Paenibacillus profundus NRIC 0885^T, strain 11^T was found to be able to ferment D-fructose, D-mannose and D-xylose. A draft genome of strain 11^T contains a cluster of genes associated with type IV pilin synthesis usually found in clostridia, and only sporadically in other Gram-positive bacteria. Genotypic, chemotaxonomic, physiological and biochemical characteristics of strain 11^T presented in this study support the creation of a novel species within the genus Paenibacillus, for which the name Paenibacillus aquistagni sp. nov. is proposed, with strain 11^T (=ZIM B1027^T =LMG 29561^T =CCM 8679^T ) as the type strain.

Marinicrinis sediminis gen. nov., sp. nov., isolated from marine sediment

Novel Gram-stain-variable, bent rods or long filaments that were endospore-forming, facultatively anaerobic, oxidase- and catalase-negative, and designated strain NC2-42T, were isolated from sediment on the coast of Weihai, China. Optimal growth occurred at 37 °C, pH 7.5 and with 2-3 % (w/v) NaCl. MK-7 was the sole respiratory quinone and meso-diaminopimelic acid was a diagnostic diamino acid in the peptidoglycan. The polar lipid profile of this novel isolate consisted of phosphatidylglycerol, phosphatidylethanolamine, an unknown phospholipid, an unknown phosphoaminolipid, two unknown glycolipids and an unknown lipid. The major cellular fatty acids in strain NC2-42T were anteiso-C15 : 0, iso-C16 : 0 and C16 : 0. The G+C content of the genomic DNA of strain NC2-42T was 58.11  mol% (HPLC). Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain NC2-42T showed the highest similarity (92.32 %) to Paenibacillus profundus within the family Paenibacillaceae. Based on data from this taxonomic study using a polyphasic approach, the isolate is proposed to represent a novel species of a new genus within the family Paenibacillaceae, with the name Marinicrinis sediminis gen. nov., sp. nov. The type strain of the type species is NC2-42T (=KCTC 33676T=MCCC 1K01238T).

Paenibacillus insulae sp. nov., isolated from soil

A Gram-stain-positive, motile, endospore-forming, and strictly aerobic rod-shaped bacterium designated DS80(T) was isolated from an island soil. The strain DS80(T) grew at temperatures between 15 and 40°C (optimum = 30°C) and at pH values ranging from 5.0 to 9.0 (optimum = 7.0). The phylogenetic analysis based on the comparisons of the 16S rRNA gene sequences showed that the isolate was affiliated to the genus Paenibacillus and was mostly related to Paenibacillus assamensis GPTSA11(T) (with the sequence similarity of 96.33%) and Paenibacillus urinalis 5402403(T)(95.48%). The G+C content of the genomic DNA was 44.0 mol% and the major fatty acids were anteiso-C15:0, iso-C15:0, iso-C16:0, and C16:1 ω11c. Strain DS80(T) contained MK-7 as the major menaquinone, and phosphatidylglycerol, phosphatidylethanolamine, and diphosphatidylglycerol as the major polar lipids. The peptidoglycan contained a major amount of meso-diaminopimelic acid. The chemotaxonomic profile of strain DS80(T) was consistent with that of Paenibacillus. However, the phenotypic properties clearly separated the strain from other species of the genus. Accordingly, a new species, Paenibacillus insulae sp. nov., is proposed (type strain =DS80(T) =JCM 17278(T) =KCTC 13833(T)).

Bacillus taiwanensis sp. nov., isolated from a soil sample from Taiwan

A Gram-stain-positive, rod-shaped, endospore-forming, aerobic bacterium (FJAT-14571T) was isolated from a soil sample in Taiwan. Strain FJAT-14571T grew at 20–40 °C (optimum 35 °C), pH 6–10 (optimum pH 8) and 0–2 % (w/v) NaCl (optimum 0 %). Phylogenetic analyses based on 16S rRNA gene sequences showed that strain FJAT-14571T was a member of the genus Bacillus and was most closely related to Bacillus oceanisediminis DSM 24771T (96.2 %). DNA–DNA relatedness between strain FJAT-14571T and B. oceanisediminis DSM 24771T was low (32.0 % ± 0.88 %). The diagnostic diamino acid of the peptidoglycan of strain FJAT-14571T was meso-diaminopimelic acid and the predominant menaquinone was MK-7 (96.6 %). The major cellular fatty acids were iso-C15 : 0 (46.4 %), anteiso-C15 : 0 (7.6 %), iso-C17 : 0 (8.2 %) and iso-C16 : 0 (10.0 %) and the DNA G+C content was 40.8 mol%. Phenotypic, chemotaxonomic and genotypic properties clearly indicated that strain FJAT-14571T represents a novel species within the genus Bacillus, for which the name Bacillus taiwanensis sp. nov. is proposed. The type strain is FJAT-14571T ( = DSM 27845T = CGMCC1.1 2698T).

Genome-based comparative analyses of Antarctic and temperate species of Paenibacillus

Antarctic soils represent a unique environment characterised by extremes of temperature, salinity, elevated UV radiation, low nutrient and low water content. Despite the harshness of this environment, members of 15 bacterial phyla have been identified in soils of the Ross Sea Region (RSR). However, the survival mechanisms and ecological roles of these phyla are largely unknown. The aim of this study was to investigate whether strains of Paenibacillus darwinianus owe their resilience to substantial genomic changes. For this, genome-based comparative analyses were performed on three P. darwinianus strains, isolated from gamma-irradiated RSR soils, together with nine temperate, soil-dwelling Paenibacillus spp. The genome of each strain was sequenced to over 1,000-fold coverage, then assembled into contigs totalling approximately 3 Mbp per genome. Based on the occurrence of essential, single-copy genes, genome completeness was estimated at approximately 88%. Genome analysis revealed between 3,043-3,091 protein-coding sequences (CDSs), primarily associated with two-component systems, sigma factors, transporters, sporulation and genes induced by cold-shock, oxidative and osmotic stresses. These comparative analyses provide an insight into the metabolic potential of P. darwinianus, revealing potential adaptive mechanisms for survival in Antarctic soils. However, a large proportion of these mechanisms were also identified in temperate Paenibacillus spp., suggesting that these mechanisms are beneficial for growth and survival in a range of soil environments. These analyses have also revealed that the P. darwinianus genomes contain significantly fewer CDSs and have a lower paralogous content. Notwithstanding the incompleteness of the assemblies, the large differences in genome sizes, determined by the number of genes in paralogous clusters and the CDS content, are indicative of genome content scaling. Finally, these sequences are a resource for further investigations into the expression of physiological attributes that enable survival under extreme conditions and selection processes that affect prokaryotic genome evolution.

Non-contiguous finished genome sequence and description of Paenibacillus gorillae sp. nov

Strain G1(T) sp. nov. is the type strain of Paenibacillus gorillae a newly proposed species within the genus Paenibacillus. This strain, whose genome is described here, was isolated in France from the fecal sample of a wild western lowland gorilla from Cameroon. P. gorillae is a facultative anaerobic, Gram-negative, rod-shaped bacterium. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 6,257,967 bp long genome (one chromosome but no plasmid) contains 5,856 protein-coding and 62 RNAs genes, including 60 tRNA genes.

Transcription of the lysine-2,3-aminomutase gene in the kam locus of Bacillus thuringiensis subsp. kurstaki HD73 is controlled by both σ54 and σK factors

Lysine 2,3-aminomutase (KAM; EC 5.4.3.2) catalyzes the interconversion of l-lysine and l-β-lysine. The transcription and regulation of the kam locus, including lysine-2,3-aminomutase-encoding genes, in Bacillus thuringiensis were analyzed in this study. Reverse transcription-PCR (RT-PCR) analysis revealed that this locus forms two operons: yodT (yodT-yodS-yodR-yodQ-yodP-kamR) and kamA (kamA-yokU-yozE). The transcriptional start sites (TSSs) of the kamA gene were determined using 5' rapid amplification of cDNA ends (RACE). A typical -12/-24 σ(54) binding site was identified in the promoter PkamA, which is located upstream of the kamA gene TSS. A β-galactosidase assay showed that PkamA, which directs the transcription of the kamA operon, is controlled by the σ(54) factor and is activated through the σ(54)-dependent transcriptional regulator KamR. The kamA operon is also controlled by σ(K) and regulated by the GerE protein in the late stage of sporulation. kamR and kamA mutants were prepared by homologous recombination to examine the role of the kam locus. The results showed that the sporulation rate in B. thuringiensis HD(ΔkamR) was slightly decreased compared to that in HD73, whereas that in HD(ΔkamA) was similar to that in HD73. This means that other genes regulated by KamR are important for sporulation.

Non-contiguous finished genome sequence and description of Gorillibacterium massiliense gen. nov, sp. nov., a new member of the family Paenibacillaceae

Strain G5(T) gen. nov., sp. nov. is the type strain of Gorillibacterium massiliense, a newly proposed genus within the family Paenibacillaceae. This strain, whose genome is described here, was isolated in France from a stool sample of a wild Gorilla gorilla subsp. gorilla from Cameroon. G. massiliense is a facultatively anaerobic, Gram negative rod. Here we describe the features of this bacterium, together with the complete genome sequence and annotation. The 5,546,433 bp long genome (1 chromosome but no plasmid) contains 5,145 protein-coding and 76 RNA genes, including 69 tRNA genes.