Paenibacillus algorifonticola sp. nov., isolated from a cold spring

Paenibacillus glufosinatiresistens sp. nov., a glufosinate-resistant bacterium isolated from sludge

A Gram-stain-positive bacterium capable of resisting 5.0 mM glufosinate, designated strain YX-27T, was isolated from a sludge sample collected from a factory in Wuxi, Jiangsu, PR China. Cells were rod-shaped, facultatively anaerobic, endospore-forming, and motile by peritrichous flagella. Growth was observed at 15-42 °C (optimum at 30 °C), pH 4.0-8.0 (optimum pH 7.0-7.5) and with 0-2.5% NaCl (w/v; optimum, 0.5 %). Strain YX-27T could tolerate up to 6.0 mM glufosinate. Strain YX-27T showed the highest 16S rRNA gene sequence similarity to Paenibacillus tianjinensis TB2019T (96.17 %), followed by Paenibacillus odorifer DSM 1539T (96.15 %), Paenibacillus sophorae S27T (96.04 %), Paenibacillus apii 7124T (96.02 %) and Paenibacillus stellifer DSM 14472T (95.87 %). The phylogenetic tree based on genome and 16S rRNA gene sequences indicated that strain YX-27T was clustered in the genus Paenibacillus but formed a separate clade. The genome size of YX-27T was 5.22 Mb with a G+C content of 57.5 mol%. The average nucleotide identity and digital DNA-DNA hybridization values between the genomes of strain YX-27T and 12 closely related type strains ranged from 70.8 to 74.8% and 19.8 to 23.0 %, respectively. The major cellular fatty acids were C16 : 0, anteiso-C15 : 0 and iso-C16 : 0. The major polar lipids were one diphosphatidylglycerol, one phosphatidylethanolamine, one phosphatidylglycerol, one phospholipid, four aminophospholipids and four unidentified lipids. The predominant respiratory quinone was MK-7. Based on phylogenetic, genomic, chemotaxonomic and phenotypic data, strain YX-27T was considered to represent a novel species for which the name Paenibacillus glufosinatiresistens sp. nov. is proposed, with YX-27T (=MCCC 1K08803T= KCTC 43611T) as the type strain.

Detergent-stable amylase production by Paenibacillus lactis strain OPSA3 isolated from soil; optimization by response surface methodology

This study aimed to isolate thermostable, alkaliphilic, and detergent-tolerant amylase-producing bacteria. Pure isolates from environmental samples were screened on a starch-based medium (pH 11), and selected isolates were identified using cultural and molecular techniques. Product optimization studies were conducted, and secreted amylase was partially purified using 40% (w/v) saturation ammonium sulfate at 4 °C. The wash performance of concentrated amylase was analyzed. A novel isolate, Paenibacillus lactis OPSA3, was selected for further studies. The isolate produced amylase optimally when grown on banana peels and soybean extracts, which are agro-wastes. Optimization by Response surface Methodology resulted in a 2.1-fold increase in alkaliphilic amylase production. A 2.46-fold purification was achieved, with an enzyme activity yield of 79.53% and specific activity of 26.19 Umg^-1. Wash performance analysis using the amylase supplemented with boiled commercial detergent (kiln®) showed good cleaning efficiency. The amylase has the potential for application as a component of green detergent.

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.

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 reveals metabolic diversity of different Paenibacillus groups

The genus Paenibacillus was originally recognized based on the 16S rRNA gene phylogeny. Recently, a standardized bacterial taxonomy approach based on a genome phylogeny has substantially revised the classification of Paenibacillus, dividing it into 23 genera. However, the metabolic differences among these groups remain undescribed. Here, genomes of 41 Paenibacillus strains comprising 25 species were sequenced, and a comparative genomic analysis was performed considering these and 187 publicly available Paenibacillus genomes to understand their phylogeny and metabolic differences. Phylogenetic analysis indicated that Paenibacillus clustered into 10 subgroups. Core genome and pan-genome analyses revealed similar functional categories among the different Paenibacillus subgroups; however, each group tended to harbor specific gene families. A large proportion of genes in the subgroups A, E, and G are related to carbohydrate metabolism. Among them, genes related to the glycoside hydrolase family were most abundant. Metabolic reconstruction of the newly sequenced genomes showed that the Embden-Meyerhof-Parnas pathway, pentose phosphate pathway, and citric acid cycle are central pathways of carbohydrate metabolism in Paenibacillus. Further, the genomes of the subgroups A and G lack genes involved in glyoxylate cycle and D-galacturonate degradation, respectively. The current study revealed the metabolic diversity of Paenibacillus subgroups assigned based on a genomic phylogeny and could inform the taxonomy of Paenibacillus. KEY POINTS: • Paenibacillus clustered into 10 subgroups. • Genomic content variation and metabolic diversity in the subgroup A, E, and G were described. • Carbohydrate transport and metabolism is important for Paenibacillus survival.

Paenibacillus bryophyllum sp. nov., a nitrogen-fixing species isolated from Bryophyllum pinnatum

A nitrogen-fixing, endospore-forming bacterium, designated strain L201^T was isolated from the leaves of Bryophyllum pinnatum growing in South China Agricultural University. Phylogenetic analysis of the 16S rRNA gene sequence indicated that strain L201^T is affiliated with the genus Paenibacillus, and closely related to Paenibacillus albidus Q4-3^T (97.4%), Paenibacillus odorifer DSM 15391^T (97.3%) and Paenibacillus borealis DSM 13188^T (97.2%). The main fatty acids components was anteiso-C_15:0 (48.1%). The predominant isoprenoid quinone was MK-7. The major polar lipids were found to be diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. The G+C content of strain L201^T was 43.9%. DNA-DNA relatedness between L201^T and the reference strain was 29.8%. Biological and biochemical tests, protein patterns, genomic DNA fingerprinting and comparison of cellular fatty acids distinguished strain L201^T from the closely related Paenibacillus species. Based on these data, the novel species Paenibacillus bryophyllum sp. nov. is proposed, with the type strain L201^T(= KCTC 33951 ^T = GDMCC 1.1251 ^T).

Paenibacillus albidus sp. nov., isolated from grassland soil

A novel bacterial strain, designed Q4-3^T, was isolated from a soil sample obtained from Qilian grassland, Qinghai, China. Phylogenetic, phenotypic, chemotaxonomic and molecular analyses were performed on the new isolate. Cells were Gram-stain-positive, facultatively anaerobic, spore-forming, motile rods with peritrichous flagella. Phylogenetic analysis based on 16S rRNA gene sequences placed strain Q4-3^T in the genus Paenibacillus, and its closest relatives were Paenibacillus odorifer JCM 21743^T, Paenibacillus typhae DSM 25190^T, Paenibacillus borealis DSM 13188^T and Paenibacillus etheri DSM 29760^T with 16S rRNA gene sequence similarities of 98.12, 97.89, 97.63 and 97.6 %, respectively. The isolate grew at 4-37 °C (optimum 28-30 °C), at pH 6.0-10.0 (optimum pH 7.5) and with 0-3 %(w/v) NaCl (optimum 1 %). The DNA of strain Q4-3^T was determined to be 48.6 mol%. The predominant menaquinone was MK-7 and the diamino acid in the cell-wall peptidoglycan was found to be meso-diaminopimelic acid. Anteiso-C15 : 0 (55.5 %), iso-C16 : 0 (14.5 %) and C16 : 0 (13.3 %) were the major fatty acids. The polar lipids contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, three unidentified aminophospholipids and one unidentified lipid. Based on these results, strain Q4-3^T is considered to represent a novel of the genus Paenibacillus, for which the name Paenibacillusalbidus nov. is proposed. The type strain is Q4-3^T (=CGMCC 1.16134^T=KCTC 33911^T).

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 konkukensis sp. nov., isolated from animal feed

A Gram-stain-positive, oxidase- and catalase-positive, aerobic, rod-shaped bacterium, designated strain SK-3146T, was isolated from animal feed. Phylogenetic analysis, based on 16S rRNA gene sequence comparisons, revealed that the strain formed a distinct lineage within the genus Paenibacillus that was closely related to Paenibacillusyunnanensis JCM 30953T (98.6 %), Paenibacillusvulneris CCUG 53270T (98.0 %) and Paenibacilluschinjuensis DSM 15045T (96.9 %). Cells were non-motile, endospore-forming and formed milky colonies on NA and R2A agar media. Growth of strain SK-3146T occurred at temperatures of 18-45 °C, at pH 6.0-9.5 and between 0.5-3.0 % NaCl (w/v). The major menaquinone was MK-7, with lesser amounts of MK-6 present. The cell wall peptidoglycan of strain SK-3146T contained meso-diaminopimelic acid. The major fatty acids were anteiso-C15 : 0 and iso-C16 : 0. The major polar lipids were diphosphatidylglycerol and phosphatidylethanolamine. The DNA G+C content was 53.8 mol% and the DNA-DNA hybridization relatedness values between strain SK-3146T and P.yunnanensis JCM 30953T and P.vulneris CCUG 53270T were 26.13±0.8 % and 38.7±0.6 %, respectively. The phenotypic, phylogenetic and chemotaxonomic results indicate that strain SK-3146T represents a novel species of the genus Paenibacillus, for which the name Paenibacillus konkukensis sp. nov. is proposed. The type strain is SK-3146T (=KACC 18876T=LMG 29568T).

Paenibacillus solani sp. nov., isolated from potato rhizosphere soil

A novel Gram-stain-positive, endospore-forming bacterium, designated FJAT-22460T, was isolated from a soil sample of a potato field in Xinjiang Autonomous Region, China. Cells were rods that were catalase-positive and motile by peritrichous flagella. The strain was found to grow at temperatures ranging from 10 to 40 °C (optimum 30 °C) and at pH 5.0-12.0 (optimum pH 7) with 0-5 % (w/v) NaCl (optimum 0 % NaCl). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain FJAT-22460T belonged to the genus Paenibacillus and exhibited 16S rRNA gene sequence similarities of 97.3, 97.2, 97.2 and 97.0 % with Paenibacillus glucanolyticus DSM 5162T, Paenibacillus lautus DSM 3035T, Paenibacillus lactis MB 1871T and Paenibacillus chibensis JCM 9905T, respectively. DNA-DNA relatedness of strain FJAT-22460T with Paenibacillus glucanolyticusDSM 5162T and Paenibacillus lautus DSM 3035T was 62.6 % and 33.3 %, respectively, lower than the 70 % accepted for species delineation. The menaquinone was identified as MK-7. The major fatty acids detected were anteiso-C15 : 0 (51.4 %), iso-C15 : 0 (5.3 %), C16 : 0 (12.1 %), iso-C16 : 0 (10.7 %) and anteiso-C17 : 0 (6.9 %). The DNA G+C content was determined to be 50.9 mol%. Phenotypic, chemotaxonomic and genotypic properties clearly indicated that isolate FJAT-22460T represents a novel species within the genus Paenibacillus, for which the name Paenibacillus solani sp. nov. is proposed. The type strain is FJAT-22460T (=DSM 100999T=CCTCC AB 2015207T).

Paenibacillusliaoningensis sp. nov., isolated from soil

A novel bacterial strain, designated as LNUB461T, was isolated from soil sample taken from the countryside of Shenyang, Liaoning Province, China. The isolate was a Gram-stain-positive, aerobiotic, motile, endospore-forming and rod-shaped bacterium. The organism grew optimally at 30-33 °C, pH 6.5-7.0 and in the absence of NaCl. Phylogenetic analysis based on the nearly full-length 16S rRNA gene sequence revealed high sequence similarity with Paenibacillus algorifonticola XJ259T (98.5 %), Paenibacillus xinjiangensis B538T (96.8 %), Paenibacillus glycanilyticus DS-1T (96.1 %) and Paenibacillus lupini RLAHU15T (96.1 %). The predominant cellular fatty acid and the only menaquinone were anteiso-C15:0 and MK-7, respectively. The main polar lipids of LNUB461T included phosphatidylethanolamine (PE), phosphatidylglycerol (PG), phosphatidylcholine (PC) and two unknown amino phospholipids (APL), and the cell-wall peptidoglycan was meso-diaminopimelic acid (A1γ). The DNA G+C content of LNUB461T was 49.1 mol%. The DNA-DNA hybridization value between LNUB461T and the most closely related species (P. algorifonticola) was 41.8 %. On the basis of these data, LNUB461T was classified as representing a novel species of the genus Paenibacillus, for which the name Paenibacillus liaoningensis sp. nov was proposed. The type strain is LNUB461T (=JCM 30712T=CGMCC 1.15101T).

Paenibacillus radicis sp. nov., an endophytic bacterium isolated from maize root

A novel Gram-stain-positive, aerobic, endospore-forming, and rod-shaped strain designated 694^T was isolated from surface-sterilized root tissue of a maize planted in the Fangshan District of Beijing, People's Republic of China. A polyphasic taxonomic study was performed on the new isolate. On the basis of 16S rRNA gene sequence similarity studies, this isolate belongs to the genus Paenibacillus. High levels of 16S rRNA gene sequence similarity were found between strain 694^T and Paenibacillus xinjiangensis DSM 30034^T (98.5 %) and Paenibacillus glycanilyticus (98.1 %), respectively. However, the DNA-DNA hybridization values between strain 694^T and its close relatives P. xinjiangensis 16970^T and Paenibacillus algorifonticola CGMCC 1.10223^T were 30.0 % and 36.7 % respectively. The DNA G+C content of strain 694^T was determined to be 46.9 mol%. The predominant respiratory quinone was identified as menaquinone-7 and the polar lipid profile was found to be composed of the major lipids diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The major fatty acids were found to be anteiso-C_15 : 0 (42.1 %), iso-C_15 : 0 (18.4 %), iso-C_16 : 0 (11.2 %) and C_16 : 0 (12.1 %). The results of physiological and biochemical tests and minor differences in the fatty acid profiles allowed a clear phenotypic differentiation of strain 694^T from the closely related species in the genus Paenibacillus. Strain 694^T is concluded to represent a novel species within the genus Paenibacillus, for which the name Paenibacillus radicis sp. nov. is proposed, with the type strain 694^T ( = CGMCC 1.15286^T = DSM 100762^T).

Paenibacillus chinensis sp. nov., isolated from maize (Zea mays L.) seeds

Four Gram-stain positive bacterial strains, designated as 4R1(T), 4R9, 4L13 and 4L18, isolated from seeds of hybrid maize (Zea mays L., Jingke 968), were investigated using a polyphasic taxonomic approach. The cells were found to be facultatively aerobic, motile, spore-forming and rod-shaped. Phylogenetic analysis based on 16S rRNA gene sequences showed that the isolates should be recognised as a species of the genus Paenibacillus, with two close neighbours being Paenibacillus nicotianae YIM h-19(T) (98.41 % similarity) and Paenibacillus hordei RH-N24(T) (98.37 %). The DNA G+C content of strain 4R1(T) was determined to be 51.6 mol %. Its polar lipid profile was found to consist of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and an unidentified lipid. The predominant respiratory quinone was identified as MK-7 and the major fatty acids were found to be anteiso-C15:0, anteiso-C12:0, anteiso-C13:0 and anteiso-C11:0. Strains 4R1(T), 4R9, 4L13 and 4L18 were clearly distinguished from the reference type strains using phylogenetic analysis, DNA-DNA hybridization and a range of physiological and biochemical characteristics. It is evident from the genotypic and phenotypic data that strains 4R1(T), 4R9, 4L13 and 4L18 represent a novel species of the genus Paenibacillus, for which the name Paenibacillus chinensis sp. nov. is proposed. The type strain is 4R1(T) (=KCTC 33672(T) = CICC 23864(T)).

Paenibacillus ripae sp. nov., isolated from bank side soil

A Gram-stain-variable, rod-shaped, non-motile and endospore-forming bacterium, designated strain HZ1T, was isolated from a sample of bank side soil from Hangzhou city, Zhejiang province, PR China. On the basis of 16S rRNA gene sequence analysis, strain HZ1T was closely related to members of the genus Paenibacillus, sharing the highest levels of sequence similarity with Paenibacillus agarexedens DSM 1327T (94.4 %), Paenibacillus sputi KIT00200-70066-1T (94.4 %). Growth occurred at 15-42 °C (optimum 30-37 °C), pH 5.0-9.5 (optimum pH 7.0-8.0) and NaCl concentrations of up to 6.0 % (w/v) were tolerated (optimum 0.5 %). The dominant respiratory quinone was MK-7 and the DNA G+C content was 40.1 mol%. The major fatty acids were anteiso-C15 : 0 and iso-C16 : 0. The major polar lipids of strain HZ1T were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and several unknown lipids. The diagnostic diamino acid found in the cell-wall peptidoglycan was meso-diaminopimelic acid. Based on its phenotypic and chemotaxonomic characteristics and phylogenetic data, strain HZ1T represents a novel species of the genus Paenibacillus, for which the name Paenibacillus ripae sp. nov. (type strain HZ1T = CCTCC AB 2014276T = LMG 28639T) is proposed.

Paenibacillus wenxiniae sp. nov., a nifH gene -harbouring endophytic bacterium isolated from maize

A novel Gram-positive, aerobic, motile, endospore-forming, rod-shaped bacterium, designated 373(T) was isolated from surface-sterilised root tissue of a maize planted in Fangshan District of Beijing, Peopole's Republic of China. A polyphasic taxonomic study was performed on the new isolate. On the basis of 16S rRNA gene sequence similarity studies, this isolate belongs to the genus Paenibacillus. The highest 16S rRNA gene sequence similarity was found between strain 373(T) and Paenibacillus hunanensis (98.1%), meanwhile the 16S rRNA gene sequence similarity between strain 373(T) and the type strains of other recognised members of the genus Paenibacillus were all below 95.6%. However, the DNA-DNA hybridization values between strain 373(T) and the type strain P. hunanensis DSM 22170(T) was 30.2%. The DNA G+C content of strain 373(T) was determined to be 46.0 mol%. The predominant respiratory quinone was identified as menaquinone-7 and the polar lipid profile was found to be composed of the major lipids diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The major fatty acids were found to consist of anteiso-C15: 0 (59.6%), anteiso-C17: 0 (12.8%) and C16: 0 (6.7%). The results of physiological and biochemical tests and minor differences in the fatty acid profiles allowed a clear phenotypic differentiation of strain 373(T) from the closely related species in this genus Paenibacillus. Strain 373(T) is concluded to represent a novel species within the genus Paenibacillus, for which the name Paenibacillus wenxiniae sp. nov. is proposed, with the type strain 373(T) (= CGMCC 1.15007 (T) = DSM100576 ).

Paenibacillus rhizoryzae sp. nov., isolated from rice rhizosphere

A Gram-stain-positive, endospore-forming, rod-shaped bacterium, designated 1ZS3-5T, was isolated from rice rhizosphere in Hunan Province, PR China. The isolate was identified as a member of the genus Paenibacillus on the basis of phenotypic characteristics and phylogenetic inference analysis. The 16S rRNA and rpoB gene (β-subunit of bacterial RNA polymerase) sequences were closely related to those of Paenibacillus taihuensis CGMCC 1.10966T with similarities of 97.2 % and 89.7 %, respectively. The DNA–DNA hybridization value between 1ZS3-5T and P. taihuensis CGMCC 1.10966T was 33.4 %. The DNA G+C content of 1ZS3-5T was 47.5 mol%. The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, unidentified aminophospholipid and unknown phospholipid. The predominant respiratory quinone was MK-7. The diamino acid found in the cell-wall peptidoglycan was meso-diaminopimelic acid. The major cellular fatty acids were anteiso-C15 : 0, iso-C15 : 0 and iso-C16 : 0. Based on these results, 1ZS3-5T is considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus rhizoryzae sp. nov. is proposed. The type strain is 1ZS3-5T ( = ACCC 19782T = DSM 29322T).

Paenibacillus physcomitrellae sp. nov., isolated from the moss Physcomitrella patens

A Gram-stain-positive, facultatively anaerobic and rod-shaped bacterium, designated strain XBT, was isolated from Physcomitrella patens growing in Beijing, China. The isolate was identified as a member of the genus Paenibacillus based on phenotypic characteristics and phylogenetic inferences. The novel strain was spore-forming, motile, catalase-negative and weakly oxidase-positive. Optimal growth of strain XBT occurred at 28°C and pH 7.0-7.5. The major polar lipids contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and several unidentified components, including one phospholipid, two aminophospholipids, three glycolipids, one aminolipid and one lipid. The predominant isoprenoid quinone was MK-7. The diamino acid found in the cell-wall peptidoglycan was meso-diaminopimelic acid. The major fatty acid components (>5 %) were anteiso-C15 : 0 (51.2 %), anteiso-C17 : 0 (20.6 %), iso-C16 : 0 (8.3 %) and C16 : 0 (6.7 %). The G+C content of the genomic DNA was 53.3 mol%. Phylogenetic analysis, based on the 16S rRNA gene sequence, showed that strain XBT fell within the evolutionary distances encompassed by the genus Paenibacillus; its closest phylogenetic neighbour was Paenibacillus yonginensis DCY84T (96.6 %). Based on phenotypic, chemotaxonomic and phylogenetic properties, strain XBT is considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus physcomitrellae sp. nov., is proposed. The type strain is XBT ( = CGMCC 1.15044T = DSM 29851T).

Paenibacillus kyungheensis sp. nov., isolated from flowers of magnolia

A Gram-staining-positive, catalase-positive, oxidase-negative, facultatively anaerobic, rod-shaped bacterium designated strain DCY88T, was isolated from flowers of magnolia. Phylogenetic analysis based on 16S rRNA gene sequence comparison revealed that the strain formed a distinct lineage within the genus Paenibacillus that was closely related to Paenibacillus hordei RH-N24T (97.8 %). The other most closely related species were Paenibacillus illinoisensis NRRL NRS-1356T (94.3 %), Paenibacillus hunanensis DSM 22170T (94.2 %), Paenibacillus peoriae DSM 8320T (93.9 %), Paenibacillus kribbensis Am49T (93.8 %) and the type species of the genus, Paenibacillus polymyxa ATCC 842T (93.3 %). Cells of the strain were endospore-forming and motile by peritrichous flagella. Strain DCY88T formed pink-pigmented colonies on trypticase soy agar and R2A agar medium. Growth of strain DCY88T occurs at temperatures 5-37 °C, at pH 4-9 and 0.5-5.5 % NaCl (w/v). The menaquinone was MK-7.The cell wall peptidoglycan of strain DCY88T contained meso-diaminopimelic acid. The major fatty acids were anteiso-C15 : 0 (61.0 %) and C16 : 0 (11.0 %). The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and an unidentified polar lipid. The strain DCY88T contained spermidine as the major polyamine. The DNA G+C content was 51.6 mol%. The DNA-DNA hybridization relatedness between strain DCY88T and P. hordei RH-N24T was 48 ± 2 %. The phenotypic, phylogenetic and chemotaxonomic results indicate that the strain DCY88T represents a novel species of the genus Paenibacillus, for which the name Paenibacillus kyungheensis sp. nov. is proposed. The type strain is DCY88T ( = JCM 19886T = KCTC 33429T).

Draft genome sequence of Paenibacillus algorifonticola sp. nov., an antimicrobial-producing strain

Paenibacillus algorifonticola sp. nov. is isolated from a cold spring sample from Xinjiang Uyghur Autonomous Region (China), a novel strain that can produce antimicrobial substance against human pathogenic bacteria and fungi, including Staphylococcus aureus and Candida albicans. Here we report a 7.60-Mb assembly of its genome sequence and other useful information, including the coding sequences (CDSs) responsible for the biosynthesis of antibacterial factors, anaerobic respiration and several immune-associated reactions. Also, prospective studies on P.algorifonticola sp. nov. in the cold spring might offer a potential source for the discovery of bioactive compounds with medical value. The data repository is deposited on the website http://www.ncbi.nlm.nih.gov/nuccore/LAQO00000000 and the accession number is LAQO00000000.

Arthrobacter liuii sp. nov., resuscitated from Xinjiang desert soil

A Gram-stain positive, aerobic, non-motile actinobacterium, designated DSXY973(T), was isolated from soil samples collected from Xinjiang desert using medium supplemented with resuscitation-promoting factor, and subjected to a polyphasic taxonomic investigation. Phylogenetic analysis based on 16S rRNA gene sequences revealed that DSXY973(T) belonged to the genus Arthrobacter and was most closely related to Arthrobacter oryzae JCM 15922(T) with 97.1 % similarity. The DNA G+C content was 67.6 %. Cells of strain DSXY973(T) mainly contained MK-9(H2), and the cell wall contained l-lysine as the primary diamino acid. The major cellular fatty acids were anteiso-C15 : 0, anteiso-C17 : 0 and iso-C15 : 0. Strain DSXY973(T) was positive for catalase and negative for oxidase activity. On the basis of its phylogenetic position and phenotypic properties, strain DSXY973(T) represents a novel species of the genus Arthrobacter, for which the name Arthrobacter liuii sp. nov. is proposed. The type strain is DSXY973(T) ( = CGMCC1.12778(T) = JCM 19864(T)).

Paenibacillus guangzhouensis sp. nov., an Fe(III)- and humus-reducing bacterium from a forest soil

A Gram-reaction-variable, rod-shaped, motile, facultatively aerobic and endospore-forming bacterium, designated strain GSS02T, was isolated from a forest soil. Strain GSS02T was capable of reducing humic substances and Fe(III) oxides. Strain GSS02T grew optimally at 35 °C, at pH 78 and in the presence of 1 % NaCl. The predominant menaquinone was MK-7. The major cellular fatty acids were anteiso-C15 : 0 and iso-C16 : 0 and the polar lipid profile contained mainly phosphatidylethanolamine, diphosphatidylglycerol and phosphatidylglycerol, with moderate amounts of two unknown aminophospholipids and a minor amount of one unknown lipid. The DNA G+C content was 53.4 mol%. Comparative 16S rRNA gene sequence analysis showed that strain GSS02T was related most closely to Paenibacillus terrigena JCM 21741T (98.1 % similarity). Mean DNA–DNA relatedness between strain GSS02T and P. terrigena JCM 21741T was 58.8±0.5 %. The phylogenetic, chemotaxonomic and phenotypic results clearly demonstrated that strain GSS02T belongs to the genus Paenibacillus and represents a novel species, for which the name Paenibacillus guangzhouensis sp. nov. is proposed. The type strain is GSS02T ( = KCTC 33171T = CCTCC AB 2013236T).

Paenibacillus ferrarius sp. nov., isolated from iron mineral soil

A Gram-reaction-positive, endospore-forming, aerobic bacterium, designated strain CY1(T), was isolated from iron mineral soil of Hunan Province, China. The isolate was rod-shaped and motile by means of peritrichous flagella. The major cellular fatty acids were anteiso-C15:0 and iso-C16:0 and the major quinone was menaquinone 7. The major polar lipids were phosphatidylglycerol and diphosphatidylglycerol phosphatidylethanolamine. The genomic DNA G+C content was 50.5 mol% and the major diagnostic diamino acid in cell-wall peptidoglycan was meso-diaminopimelic acid. Phylogenetic analyses based on the 16S rRNA gene sequence indicated that strain CY1(T) is most closely related to Paenibacillus chondroitinus DSM 5051(T) (97.7% 16S rRNA gene sequence similarity), Paenibacillus pocheonensis Gsoil 1138(T) (97.4%) and Paenibacillus frigoriresistens YIM 016(T) (97.0%). DNA-DNA hybridization dissociation values were lower than 49% with the most closely related species. On the basis of phenotypic, chemotaxonomic and phylogenetic evidence, strain CY1(T) is affiliated to the genus Paenibacillus, but could be distinguished from the species of this genus. A novel species with the name Paenibacillus ferrarius sp. nov. is proposed. The type strain is CY1(T) ( =KCTC 33419(T) =CCTCC AB 2013369(T)).

Paenibacillus lemnae sp. nov., an endophytic bacterium of duckweed (Lemna aequinoctialis)

A Gram-stain-variable, rod-shaped and endospore-forming bacterium, designated strain L7-75, was isolated from duckweed (Lemna aequinoctialis). Cells were motile with a monopolar flagellum. Phylogenetic analysis of the 16S rRNA gene sequence indicated that strain L7-75(T) belonged to the genus Paenibacillus, and the closest phylogenetically related species were Paenibacillus uliginis N3/975(T) (98.5% 16S rRNA gene sequence similarity), Paenibacillus purispatii ES_M17(T) (98.5%), Paenibacillus lactis MB 1871(T) (98.2%), Paenibacillus campinasensis 324(T) (97.7%), Paenibacillus glucanolyticus S93(T) (97.7%) and Paenibacillus lautus ATCC 43898(T) (97.4%). Growth of strain L7-75(T) was observed at pH 7-10 and at 20-40 °C, and NaCl concentrations up to 5% (w/v) were tolerated. Major cellular fatty acids included anteiso-C15 : 0, C16 : 0 and anteiso-C17:0 that were present at 36.0%, 14.2 % and 10.0% of the total cellular fatty acid profile, respectively. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and phosphatidyl-N-methylethanolamine. MK-7 was the predominant menaquinone. The diamino acid found in the cell-wall peptidoglycan was meso-diaminopimelic acid. The DNA G+C content was 49.1 mol% (Tm). DNA-DNA relatedness values between strain L7-75(T) and its closest relatives ranged from 4.4 to 47.8%. These results indicate that strain L7-75(T) represents a novel species of the genus Paenibacillus, for which the name Paenibacillus lemnae sp. nov. is proposed. The type strain is L7-75(T) ( = BCC 67838(T) = NBRC 109972(T)).

Paenibacillus abyssi sp. nov., isolated from an abyssal sediment sample from the Indian Ocean

A Gram-positive, rod-shaped bacterium, designated strain SCSIO N0306(T), was isolated from an abyssal sediment sample collected from the Indian Ocean. The isolate was found to grow optimally at 0-2 % (w/v) NaCl, pH 7.0 and 30 °C. Comparative analysis of the 16S rRNA gene sequence showed that the isolate SCSIO N0306(T) belongs phylogenetically to the genus Paenibacillus, and to be most closely related to P. algorifonticola XJ259(T) (with 95.47 % sequence similarity), sharing less than 95.0 % sequence similarity with all other taxa of this genus. Chemotaxonomic analysis revealed MK-7 as the major isoprenoid quinone, the DNA G+C content was determined to be 45.5 mol%, and anteiso-C15:0, C16:0, and iso-C15:0 were identified as the major fatty acids. On the basis of this polyphasic taxonomic data, isolate SCSIO N0306(T) is considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus abyssi sp. nov. is proposed. The type strain is SCSIO N0306(T) (= DSM 26238(T) = CGMCC 1.12987(T)).

Paenibacillus doosanensis sp. nov., isolated from soil

A Gram-stain-positive, aerobic, endospore-forming bacterium, designated CAU 1055T, was isolated from soil and its taxonomic position was investigated using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequence comparison revealed that the strain formed a distinct lineage within the genus Paenibacillus and was most closely related to Paenibacillus contaminans CKOBP-6T (similarity, 95.2 %) and Paenibacillus terrigena A35T (similarity, 95.2 %). The levels of 16S rRNA gene sequence similarity with other species of the genus Paenibacillus , including the type species of the genus, Paenibacillus polymyxa IAM 13419T (similarity, 91.7 %), were all <94.6 %. Strain CAU 1055T contained MK-7 as the only isoprenoid quinone and anteiso-C15 : 0 and iso-C16 : 0 as the major fatty acids. The cell-wall peptidoglycan of strain CAU 1055T contained meso-diaminopimelic acid. The polar lipids were composed of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, lysyl-phospatidylglycerol and three unidentified aminophospholipids. The DNA G+C content was 48.3 mol%. The results of physiological and biochemical tests allowed phenotypic differentiation of strain CAU 1055T from closely related recognized species. On the basis of phenotypic data and phylogenetic inference, strain CAU 1055T should be classified in the genus Paenibacillus , as a member of a novel species, for which the name Paenibacillus doosanensis sp. nov. is proposed. The type strain is CAU 1055T ( = KCTC 33036T = CCUG 63270T).

Paenibacillus darwinianus sp. nov., isolated from gamma-irradiated Antarctic soil

A novel bacterium, strain Br(T), was isolated from gamma-irradiated soils of the Britannia drift, Lake Wellman Region, Antarctica. This isolate was rod-shaped, endospore forming, Gram-stain-variable, catalase-positive, oxidase-negative and strictly aerobic. Cells possessed a monotrichous flagellum. Optimal growth was observed at 18 °C, pH 7.0 in PYGV or R2A broth. The major cellular fatty acid was anteiso-C15 : 0 (63.4 %). Primary identified lipids included phosphatidylethanolamine, diphosphatidylglycerol and phosphatidylglycerol. Total phospholipid was 60 % (w/w) of the total lipid extract. MK-7 was the dominant isoprenoid quinone. The genomic DNA G+C content was 55.6 mol%. Based on 16S rRNA gene sequence similarity, strain Br(T) clusters within the genus Paenibacillus with similarity values ranging from 93.9 to 95.1 %. Phylogenetic analyses by maximum-likelihood, maximum-parsimony and neighbour-joining methods revealed that strain Br(T) clusters with Paenibacillus daejeonensis (AF290916), Paenibacillus tarimensis (EF125184) and Paenibacillus pinihumi (GQ423057), albeit with weak bootstrap support. On the basis of phenotypic, chemotaxonomic and phylogenetic characteristics, we propose that strain Br(T) represents a novel species, Paenibacillus darwinianus sp. nov. The type strain is Br(T) ( = DSM 27245(T) = ICMP 19912(T)).

Salinibacillus xinjiangensis sp. nov., a halophilic bacterium from a hypersaline lake

A Gram-positive, endospore-forming, rod-shaped bacterium, designated isolate J4T, was isolated from a neutral saline lake sample from Xinjiang Uyghur Autonomous Region, China, and subjected to a polyphasic taxonomic investigation. Phylogenetic analysis based on 16S rRNA gene sequence revealed that strain J4T is most closely related to Salinibacillus aidingensis 25-7T (with 96.7 % similarity), Salinibacillus kushneri 8-2T (96.5 %), Ornithinibacillus scapharcae TW25T (96.4 %), Salirhabdus euzebyi CVS-14T (96.4 %) and Ornithinibacillus californiensis MB-9T (96.2 %). Chemotaxonomic analysis showed menaquinone-7 (MK-7) to be the major isoprenoid quinone of strain J4T; diphosphatidylglycerol and phosphatidylglycerol were the major cellular polar lipids and the cell wall contained meso-diaminopimelic acid as the diagnostic diamino acid. The major cellular fatty acids were iso-C15 : 0 and anteiso-C15 : 0. The genomic DNA G+C content of strain J4T was determined to be 36.2 mol%. Strain J4T was positive for catalase activity and negative for oxidase activity. Strain J4T was observed to grow at 25–50 °C (optimal 35–42 °C), pH 6.5–8.0 (optimal 7.0–7.5) and in media containing 1–21 % (w/v) NaCl (optimal 9–12 %). Based on these data, strain J4T represents a novel species of the genus Salinibacillus and the name Salinibacillus xinjiangensis sp. nov. is proposed. The type strain is J4T ( = CGMCC 1.12331T = JCM 18732T).

Paenibacillus selenitireducens sp. nov., a selenite-reducing bacterium isolated from a selenium mineral soil

A Gram-stain-positive, rod-shaped, facultatively anaerobic bacterium, designated strain ES3-24(T), was isolated from a selenium mineral soil. The isolate was endospore-forming, nitrate-reducing and motile by means of peritrichous flagella. The major menaquinone was menaquinone 7 (MK-7) and the predominant fatty acids (>5%) were anteiso-C15:0, iso-C16:0, C16:0 and anteiso-C17:0. The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine and two unknown aminophospholipids. Strain ES3-24(T) contained meso-diaminopimelic acid in the cell-wall peptidoglycan and the DNA G+C content was 49.6 mol%. According to phylogenetic analysis based on the 16S rRNA gene sequence, strain ES3-24(T) was most closely related to Paenibacillus terrigena A35(T), with 16S rRNA gene sequence identity of 98.3%, while the other members of the genus Paenibacillus had 16S rRNA gene sequence identities of less than 95.0%. DNA-DNA relatedness between strain ES3-24(T) and P. terrigena CCTCC AB206026(T) was 39.3 %. In addition, strain ES3-24(T) showed obvious differences from closely related species in major polar lipids, nitrate reduction and other physiological and biochemical characteristics. The data from our polyphasic taxonomic study reveal that strain ES3-24(T) represents a novel species of the genus Paenibacillus, for which the name Paenibacillus selenitireducens sp. nov. is proposed. The type strain is ES3-24(T) ( = KCTC 33157(T) = CCTCC AB2013097(T)).

Paenibacillus taihuensis sp. nov., isolated from an eutrophic lake

Two Gram-stain-negative, facultatively anaerobic and endospore-forming rod-shaped bacterial strains, THMBG22T and R24, were isolated from decomposing algal scum. Phylogenetic analysis of 16S rRNA gene sequences showed that the two strains were closely related to each other (99.7 % similarity) and that they were also closely related to Paenibacillus sacheonensis DSM 23054T (97–97.1 %) and Paenibacillus phyllosphaerae DSM 17399T (96.1–96.4 %). This affiliation was also supported by rpoB-based phylogenetic analyses. Growth was observed at 20–40 °C (optimum, 30–37 °C) and at pH 5.0–9.0 (optimum, pH 6.0–7.0). The cells contained MK-7 as the sole respiratory quinone and anteiso-C15 : 0 as the major cellular fatty acid. Their cellular polar lipids were composed of phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine and 12 unidentified polar lipids. The diamino acid of their cell-wall peptidoglycan was meso-diaminopimelic acid. The DNA–DNA hybridization value between THMBG22T and R24 was 84 %, and DNA–DNA relatedness to the most closely related species with a validly published name ( P. sacheonensis ) was 35–37 %. These results supported the assignment of the new isolates to the genus Paenibacillus and also distinguished them from the previously described species of the genus Paenibacillus . Hence, it is proposed that strains THMBG22T and R24 represent a novel species of the genus Paenibacillus , with the name Paenibacillus taihuensis sp. nov. The type strain is THMBG22T ( = CGMCC 1.10966T = NBRC 108766T).

Gracilibacillus xinjiangensis sp. nov., a new member of the genus Gracilibacillus isolated from Xinjiang region, China

A Gram-positive, endospore-forming, rod-shaped bacterium, designated isolate J2(T) was isolated from a soil sample from Xinjiang Uyghur Autonomous Region, China. The isolate was observed to grow at 16-46 °C and pH 6.5-8.0. Chemotaxonomic analysis showed menaquinone-7 (MK-7) to be the major isoprenoid quinone; diphosphatidylglycerol, phosphatidylglycerol, one aminophospholipid, two phosphoglycolipids and one glycolipid as the major cellular polar lipids; and anteiso-C15:0, iso-C15:0, anteiso-C17:0 and C16:0 as the major fatty acids. Comparative analyses of the 16S rRNA gene sequence showed that strain J2(T) is most closely related to Gracilibacillus ureilyticus (with 98.8 % similarity), Gracilibacillus dipsosauri (97.2 %), Gracilibacillus quinghaiensis (97.1 %) and Gracilibacillus thailandensis (97.0 %). The DNA-DNA reassociation values between strain J2(T) and G. ureilyticus MF38(T), G. dipsosauri DD1(T), G. quinghaiensis YIM-C229(T) and G. thailandensis TP2-8(T) were 29.8 ± 3.7, 23.0 ± 3.5, 15.8 ± 4.9 and 15.9 ± 5.0 %, respectively. The genomic DNA G+C content of strain J2(T) was determined to be 36.5 mol%. Based on these data, strain J2(T) is considered as a novel species of the genus Gracilibacillus, for which the name Gracilibacillus xinjiangensis sp. nov. is proposed. The type species is J2(T) (= CGMCC 1.12449(T) = JCM 18859(T)).

Paenibacillus typhae sp. nov., isolated from roots of Typha angustifolia L

A Gram-stain-positive, facultatively anaerobic and rod-shaped bacterium, designated strain xj7T, was isolated from roots of Typha angustifolia L. growing in Beijing Cuihu Wetland, China. The isolate was identified as a member of the genus Paenibacillus based on phenotypic characteristics and phylogenetic inference. The novel strain was spore-forming, motile, catalase-positive and oxidase-negative. Optimal growth of strain xj7T occurred at 28–30 °C and pH 7.0–7.5. Diphosphatidylglycerol was the most abundant polar lipid and occurred along with phosphatidylglycerol, phosphatidylethanolamine, one unknown phospholipid and three unknown aminophospholipids. The diamino acid found in the cell-wall peptidoglycan was meso-diaminopimelic acid. The predominant isoprenoid quinone was MK-7. The major fatty acid components were anteiso-C15 : 0 (56.1 %), iso-C16 : 0 (9.1 %), C16 : 0 (8.0 %), iso-C14 : 0 (6.3 %) and iso-C15 : 0 (5.1 %). The G+C content of genomic DNA was 47.9 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain xj7T fell within the evolutionary radiation encompassed by the genus Paenibacillus , its closest neighbours were Paenibacillus borealis KK19T (97.5 %) and Paenibacillus durus DSM 1735T (97.1 %). However, the DNA–DNA relatedness values between strain xj7T and P. borealis KK19T and between strain xj7T and P. durus DSM 1735T, were both 35 %. Based on phenotypic, chemotaxonomic and phylogenetic properties, strain xj7T is considered to represent a novel species of the genus Paenibacillus , for which the name Paenibacillus typhae sp. nov. is proposed. The type strain is xj7T ( = CGMCC 1.11012T = DSM 25190T).

Paenibacillus catalpae sp. nov., isolated from the rhizosphere soil of Catalpa speciosa

A bacterial strain, designated D75(T), was isolated from the rhizosphere soil of Catalpa speciosa. Phylogenetic analysis based on the complete 16S rRNA gene sequence revealed that strain D75(T) was a member of the genus Paenibacillus. High levels of 16S rRNA gene sequence similarity were found between strain D75(T) and Paenibacillus glycanilyticus DS-1(T) (99.2 %), Paenibacillus xinjiangensis B538(T) (97.5 %) and Paenibacillus castaneae Ch-32(T) (97.2 %). The chemotaxonomic properties of strain D75(T) were consistent with those of the genus Paenibacillus: the cell-wall peptidoglycan type was based on meso-diaminopimelic acid (A1γ), the predominant menaquinone was MK-7, and the major fatty acids were anteiso-C15 : 0, iso-C16 : 0 and C16 : 0. However, levels of DNA-DNA relatedness between strain D75(T) and P. glycanilyticus NBRC 16618(T), P. xinjiangensis DSM 16970(T) and P. castaneae DSM 19417(T) were 35, 20 and 18 %, respectively. On the basis of phenotypic and chemotaxonomic analyses, phylogenetic data and DNA-DNA relatedness values, strain D75(T) is considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus catalpae sp. nov. is proposed. The type strain is D75(T) ( = DSM 24714(T) = CGMCC 1.10784(T)).

Identification and characterization of psychrotolerant sporeformers associated with fluid milk production and processing

Psychrotolerant spore-forming bacteria represent a major challenge to the goal of extending the shelf life of pasteurized dairy products. The objective of this study was to identify prominent phylogenetic groups of dairy-associated aerobic sporeformers and to characterize representative isolates for phenotypes relevant to growth in milk. Analysis of sequence data for a 632-nucleotide fragment of rpoB showed that 1,288 dairy-associated isolates (obtained from raw and pasteurized milk and from dairy farm environments) clustered into two major divisions representing (i) the genus Paenibacillus (737 isolates, including the species Paenibacillus odorifer, Paenibacillus graminis, and Paenibacillus amylolyticus sensu lato) and (ii) Bacillus (n = 467) (e.g., Bacillus licheniformis sensu lato, Bacillus pumilus, Bacillus weihenstephanensis) and genera formerly classified as Bacillus (n = 84) (e.g., Viridibacillus spp.). When isolates representing the most common rpoB allelic types (ATs) were tested for growth in skim milk broth at 6°C, 6/9 Paenibacillus isolates, but only 2/8 isolates representing Bacillus subtypes, grew >5 log CFU/ml over 21 days. In addition, 38/40 Paenibacillus isolates but only 3/47 Bacillus isolates tested were positive for β-galactosidase activity (including some isolates representing Bacillus licheniformis sensu lato, a common dairy-associated clade). Our study confirms that Paenibacillus spp. are the predominant psychrotolerant sporeformers in fluid milk and provides 16S rRNA gene and rpoB subtype data and phenotypic characteristics facilitating the identification of aerobic spore-forming spoilage organisms of concern. These data will be critical for the development of detection methods and control strategies that will reduce the introduction of psychrotolerant sporeformers and extend the shelf life of dairy products.