Desertivirga arenae gen. nov., sp. nov. and Desertivirga brevis sp. nov., isolated from desert soil, and reclassification of Pedobacter xinjiangensis as Desertivirga xinjiangensis comb. nov. and Pedobacter mongoliensis as Paradesertivirga mongoliensis gen.nov., comb. nov.

Two novel bacterial strains, designated as SYSU D00823T and SYSU D00873T, were isolated from sandy soil of the Gurbantunggut Desert in Xinjiang, north-west China. SYSU D00823T and SYSU D00873T shared 99.0 % 16S rRNA gene sequence identity, and were both most closely related to Pedobacter xinjiangensis 12157T with 96.1 % and 96.0 % similarities, respectively. Phylogenetic and phylogenomic analyses revealed that the two isolates and P. xinjiangensis 12157T formed a separate distinct cluster in a stable subclade with the nearby species Pedobacter mongoliensis 1-32T, as well as the genera Pararcticibacter and Arcticibacter. Furthermore, P. mongoliensis 1-32T formed a separate deep-branching lineage and did not form a cluster with members of the genus Pedobacter. The average nucleotide identity and digital DNA-DNA hybridization values between SYSU D00823T and SYSU D00873T and related species were well below the thresholds for species delineation (<81.0 % and <24.0 %, respectively). The genomes of SYSU D00823T and SYSU D00873T were 6.19 and 6.43 Mbp in size with 40.4 % and 40.5 % DNA G+C contents, respectively. The predominant fatty acids (>10 %) of SYSU D00823T and SYSU D00873T were iso-C15 : 0, iso-C17 : 0 3-OH and summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c). Menaquinone-7 was the only respiratory quinone. The major polar lipids were phosphatidylethanolamine, glycosphingolipid, aminoglycolipid/glycolipid, aminophospholipid and three or four unidentified polar lipids. These data indicated that strains SYSU D00823T and SYSU D00873T should be assigned to two novel species of a new genus within the family Sphingobacteriaceae, for which the names Desertivirga arenae gen. nov., sp. nov. and Desertivirga brevis sp. nov. are proposed. The type strains are SYSU D00823T (=CGMCC 1.18630T=MCCC 1K04973T=KCTC 82278T) and SYSU D00873T (=CGMCC 1.18629T=MCCC 1K04974T=KCTC 82281T), respectively. Accordingly, the reclassification of P. xinjiangensis as Desertivirga xinjiangensis comb. nov., and P. mongoliensis as Paradesertivirga mongoliensis gen. nov., comb. nov. are also proposed.

Pedobacter rhodius sp. nov. and Pedobacter punctiformis sp. nov., isolated from soil.

Two Gram-staining negative, catalase- and oxidase-positive, pinkish-colored and rod-shaped strains, designated SJ11T and HCMS5-2 T, were isolated from soil in South Korea. The growth of strain SJ11T was observed from 15℃ to 35℃ (optimum, 30℃), from pH 6.0 to 11.0 (optimum, pH 6.0-7.0) and with NaCl 0-1% (w/v) (optimum, 0%) and that of strain HCMS5-2 T was observed from 4℃ to 40℃ (optimum, 25℃), from pH 6.0 to pH 8.0 (optimum, pH 7.0) and with NaCl 0-5% (w/v) (optimum, 0-1%). Phylogenetic analysis based on 16S rRNA gene sequences showed that both strains belonged to the genus Pedobacter. Strain SJ11T had the highest 16S rRNA similarities with Pedobacter jejuensis THG-DR3T (98.5%) and strain HCMS5-2 T had the highest similarities with Pedobacter nototheniae 36B243T (98.7%). The digital DNA-DNA hybridization value of strain SJ11T with Pedobacter jejuensis THG-DR3T was 23.6%, with an average nucleotide identity value of 79.6%, and that of strain HCMS5-2 T with Pedobacter nototheniae 36B243T was 26.4%, with an average nucleotide identity value of 83.1%. The predominant cellular fatty acids (> 10%) of SJ11T and HCMS5-2 T were iso-C15:0, summed feature 3 (comprising C16:1ω7c and/or C16:1ω6c) and iso-C17:0 3-OH. The genome size of strain SJ11T was approximately 4.7 Mb with a G + C content of 37.7% and that of strain HCMS5-2 T was approximately 4.1 Mb with a G + C content of 36.4%. The major polar lipid and respiratory quinone of SJ11T and HCMS5-2 T were phosphatidylethanolamine and menaquinone NK-7, respectively. Results of this study showed that strains SJ11T and HCMS5-2 T belonged to the genus Pedobacter as novel species, of which the name Pedobacter rhodius sp. nov., with the type strain SJ11T (= KACC 22884 T = TBRC 16597 T) and Pedobacter punctiformis sp. nov., with the type strain HCMS5-2 T (= KACC 22863 T = TBRC 16598 T) were respectively proposed.

Genome-based classification of Pedobacter polysacchareus sp. nov., isolated from Antarctic soil producing exopolysaccharide.

A psychrotolerant bacterial strain, designated ZS13-49T, with strong extracellular polysaccharide synthesis ability was isolated from soil collected in Antarctica and subjected to polyphasic taxonomic and comparative genomics. Chemotaxonomic features, including fatty acids, and polar lipid profiles, support the assignment of strain ZS13-49T to the genus Pedobacter. 16S rRNA gene phylogeny demonstrates that strain ZS13-49T forms a well-supported separate branch as a sister clade to Pedobacter gandavensis LMG 31462T and is clearly separated from Pedobacter steynii DSM 19110T and Pedobacter caeni DSM 16990T. Phylogenetic analysis showed strain ZS13-49T shared the highest 16S rRNA gene sequence similarity (99.9%) with P. gandavensis LMG 31462T. However, the digital DNA-DNA hybridization (dDDH), average nucleotide identity (ANI) value and average amino identity (AAI) value between strain ZS13-49T and P. gandavensis LMG 31462T were 26.5%, 83.3%, and 87.5%, respectively. Phylogenomic tree and a comparative genomic analysis indicated distinct characteristics to distinguish strain ZS13-49T from the closely related species. The complete genome sequence of strain ZS13-49T consists of 5 830 353 bp with 40.61% G + C content. Genomic features of strain ZS13-49T adapted to Antarctic environment were also revealed. Based on the phenotypic, chemotaxonomic, and genomic data, strain ZS13-49T could be assigned to a novel species within the genus Pedobacter for which the name Pedobacter polysacchareus sp. nov. is proposed. The type strain is ZS13-49T ( = CCTCC AB 2019394T = KCTC 72824T).

Nitrogen source as a modulator of the metabolic activity of Pedobacter lusitanus NL19: a transcriptomic approach.

Secondary metabolites (SMs) are compounds with relevant biological activities. Their production under laboratory conditions, especially in broth, is still challenging. An example is the pedopeptins, which are nonribosomal peptides active against some bacteria listed by the WHO for which new antibiotics are urgently needed. Their biosynthesis is inhibited by high concentrations of peptone from casein (PC) in tryptic soy broth (TSB), and we applied a RNA-seq approach to identify Pedobacter lusitanus NL19 cellular pathways modulated by this condition. Results were validated by qPCR and revealed 261 differentially expressed genes (DEGs), 46.3% of them with a predicted biological function. Specifically, high concentration of PC significantly repressed the de novo biosynthesis of biotin (- 60X) and the production of nonribosomal peptide synthetases (NRPS) of pedopeptins (about - 14X), but no effect was observed on the expression of other NRPS. Transcription of a L-Dap synthesis operon that includes a protein with a σ70-like domain was also reduced (about - 7X). High concentrations of PC led to a significant overexpression of MFS and RND efflux pumps and a ferrous iron uptake system, suggesting the redirection of cell machinery to export compounds such as amino acids, sugars and metal divalent cations, alongside with a slight increase of iron import. KEY POINTS: • Higher concentrations of phosphate sources highly repress many operons • High concentrations of peptone from casein (PC) cause biotin's operon repression • High concentrations of PC downregulate the production of peptides of unknown function.

Pedobacter segetis sp. nov., a Novel Bacterium Isolated from Soil.

A Gram-negative, motile by gliding, rod-shaped, aerobic bacterium, designated SD-bT, was isolated from a soil sample collected on Dokdo Island, South Korea. A polyphasic approach based on phenotypic, phylogenetic, and genomic analyses was used to characterize the new isolate. Phylogenetic analysis of 16S rRNA gene sequence showed that strain SD-bT belonged to the family Sphingobacteriaceae and most closely related to Pedobacter psychrophilus P4487AT (95.9% similarity). The isolate contained MK-7 as the predominant respiratory quinone; its main polar lipid was phosphatidylethanolamine; and the major fatty acids were summed feature 3 (C16:1 ω7c/C16:1 ω6c; 32.0%), C15:0 iso (19.1%), C17:0 iso 3-OH (8.3%), and C16:0 (8.2%). The draft genome had a length of 3,842,102 bp with a G+C content of 36.0 mol%, predicting 3282 coding sequences, 3 rRNA genes, 3 ncRNAs, and 36 tRNAs genes. The digital DNA-DNA hybridization and average nucleotide identity values between strain SD-bT and P. psychrophilus LMG 29436T were 22.0% and 78.9%, respectively. The results of phenotypic properties, genotypic distinctiveness, and chemotaxonomic features support the discrimination of SD-bT from its phylogenetic relatives. Pedobacter segetis sp. nov. is therefore proposed with SD-bT (= KCTC 82351T = JCM 34283T) as the type strain.

Pedobacter riviphilus sp. nov., isolated from stream sediment.

A Gram-stain-negative, aerobic, motile by gliding, rod-shaped and pink-coloured bacterium, designated strain SW-16T, was isolated from the sediment of small stream in the Republic of Korea. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain SW-16T formed a lineage within the genus Pedobacter of the family Sphingobacteriaceae. Phylogenetic analysis also showed that strain SW-16T was most closely related to Pedobacter soli 15-51T (98.0% 16S rRNA gene sequence similarity), Pedobacter humicola R135T (97.5%), Pedobacter suwonensis 15-52T (97.4%), Pedobacter sandarakinus DS-27T (97.0%) and Pedobacter kyungheensis THG-T17T (97.0%). Growth was observed at 10-37 °C (optimum at 30 °C), pH 6-8 (optimum at pH 7) and with 0-2.0 % NaCl (optimum at 0%). The major fatty acids of the bacterial strain were iso-C15 : 0, iso-C17 : 0 3-OH and summed feature 3 (iso-C15 : 0 2-OH and/or C16 : 1 ω7c). The predominant respiratory quinone was menaquinone-7 and the major polar lipids were phosphatidylethanolamine, two unidentified amino lipids, one unidentified phospholipid and three unidentified lipids. The genome size of strain SW-16T was 5.8 Mbp and the G+C content was 38.5 mol%. Based on the results of phenotypic, genomic and phylogenetic analyses, strain SW-16T represents a novel species of the genus Pedobacter, for which the name Pedobacter riviphilus sp. nov. is proposed. The type strain is SW-16T (=KEMB 1602-396T=KCTC 82079T=JCM 34181T).

Exploration of Social Spreading Reveals That This Behavior Is Prevalent among Pedobacter and Pseudomonas fluorescens Isolates and That There Are Variations in the Induction of the Phenotype.

Within soil, bacteria are found in multispecies communities, where interactions can lead to emergent community properties. Studying bacteria in a social context is critical for investigating community-level functions. We previously showed that cocultured Pseudomonas fluorescens Pf0-1 and Pedobacter sp. V48 engage in interspecies social spreading (ISS) on a hard agar surface, a behavior which required close contact and depended on the nutritional environment. Here, we investigate whether social spreading is widespread among P. fluorescens and Pedobacter isolates and whether the requirements for interaction vary. We find that this phenotype is not restricted to the interaction between P. fluorescens Pf0-1 and Pedobacter sp. V48 but is a prevalent behavior found in one clade in the P. fluorescens group and two clades in the Pedobacter genus. We show that the interaction with certain Pedobacter isolates occurred without close contact, indicating induction of spreading by a putative diffusible signal. As with ISS by Pf0-1+V48, the motility of interacting pairs is influenced by the environment, with no spreading behaviors (or induction of motility) observed under high nutrient conditions. While Pf0-1+V48 require low nutrient but high NaCl conditions, in the broader range of interacting pairs, the high salt influence was variable. The prevalence of motility phenotypes observed here and found within the literature indicates that community-induced locomotion in general, and social spreading in particular, is likely important within the environment. It is crucial that we continue to study microbial interactions and their emergent properties to gain a fuller understanding of the functions of microbial communities. IMPORTANCE Interspecies social spreading (ISS) is an emergent behavior observed when Pseudomonas fluorescens Pf0-1 and Pedobacter sp. V48 interact, during which both species move together across a surface. Importantly, this environment does not permit the movement of either individual species. This group behavior suggests that communities of microbes can function in ways not predictable by knowledge of the individual members. Here, we have asked whether ISS is widespread and thus potentially of importance in soil microbial communities. The significance of this research is the demonstration that surface spreading behaviors are not unique to the Pf0-1-V48 interaction but rather is a more widespread phenomenon observed among members of distinct clades of both P. fluorescens and Pedobacter isolates. Furthermore, we identify differences in mechanisms of signaling and nutritional requirements for ISS. Emergent traits resulting from bacterial interactions are widespread, and their characterization is necessary for a complete understanding of microbial community function.

Complete Genome Sequence of Pedobacter sp. PAMC26386 and Their Low Temperature Application in Arabinose-containing Polysaccharides Degradation.

Pedobacter are a representative genus of soil-associated bacteria. Here we have provided the complete genome sequence of Pedobacter sp. PAMC26386 isolated from Antarctic soil, and functionally annotated the genome, describing the unique features of carbohydrate active enzymes (CAZymes) and α-L-arabinofuranosidase (α-L-ABF). The genome of Pedobacter sp. PAMC26386 is circular and comprises 4,796,773 bp, with a 38.2% GC content. The genome encodes 4,175 genes, including 7 rRNA and 44 tRNA genes. We identified 172 genes (8 auxiliary activities, 8 carbohydrate binding modules, 23 carbohydrate esterases, 86 glycoside hydrolases, 42 glycosyl transferases, and 5 polysaccharide lyases) related to CAZymes using the dbCAN2 tool. We checked enzyme activity on 11 substrates using the AZCL assay and obtained strong activity for arabinooligosaccharide and hemicellulose. This includes information regarding α-L-ABF, which is active at low temperatures, based on the annotation results. Our findings on Pedobacter sp. PAMC26386 provide the basis for research in the future. The favorable properties of Pedobacter sp. PAMC26386 make it a good candidate for industrial applications involving low temperatures.

Feeding on fungi: genomic and proteomic analysis of the enzymatic machinery of bacteria decomposing fungal biomass.

Dead fungal biomass is an abundant source of nutrition in both litter and soil of temperate forests largely decomposed by bacteria. Here, we have examined the utilization of dead fungal biomass by the five dominant bacteria isolated from the in situ decomposition of fungal mycelia using a multiOMIC approach. The genomes of the isolates encoded a broad suite of carbohydrate-active enzymes, peptidases and transporters. In the extracellular proteome, only Ewingella americana expressed chitinases while the two Pseudomonas isolates attacked chitin by lytic chitin monooxygenase, deacetylation and deamination. Variovorax sp. expressed enzymes acting on the side-chains of various glucans and the chitin backbone. Surprisingly, despite its genomic potential, Pedobacter sp. did not produce extracellular proteins to decompose fungal mycelia but presumably feeds on simple substrates. The ecological roles of the five individual strains exhibited complementary features for a fast and efficient decomposition of dead fungal biomass by the entire bacterial community.

Engineering the heparin-binding pocket to enhance the catalytic efficiency of a thermostable heparinase III from Bacteroides thetaiotaomicron.

Heparinase has attracted much attention because of its applications in pharmaceutical industry. Herein, the heparinases III from Flavobacterium heparinum (FhepIII) and Bacteroides thetaiotaomicron (BhepIII) were firstly comparatively characterized. BhepIII showed higher catalytic activity and thermostability toward heparin comparing to FhepIII. To further upgraded BhepIII, a protein engineering approach based on B-factor was performed. By site-saturated mutagenesis of the flexible residues within an 8 Šradius around the catalytic residue, Asp321 and Ser264 were identified as essential residues for catalytic efficiency and thermostability, respectively. D321Q mutation enhanced catalytic efficiency (kcat/Km) with a 68.4% increase by increasing the surface potential while S264 F mutation increased thermostability with a half-time at 50℃ (t1/250℃) of 3.8 h versus 2.7 h of the wild-type by increasing rigidity and interactions within the active pocket. Double mutation of S264 F and D321Q resulted in a 245% increase in kcat/Km but with a decreased t1/250℃ (2.0 h). E105R mutation that generated a 348% increase in kcat/Km was further identified by electric potential engineering of the pocket tunnel. Eventually, the variant E105R/S264 F that showed a 418% increase in kcat/Km without compromise of thermostability was constructed. The engineered E105R/S264 F has a great potential for the commercial production of low molecular weight heparin in the future.

Biochemical characterization of a novel α-L-fucosidase from Pedobacter sp. and its application in synthesis of 3'-fucosyllactose and 2'-fucosyllactose.

Fucosyllactoses have gained much attention owing to their multiple functions, including prebiotic, immune, gut, and cognition benefits. In this study, human milk oligosaccharide (HMO) 2'-fucosyllactose (α-L-Fuc-(1,2)-D-Galß-1,4-Glu, 2'FL) and its isomer 3'-fucosyllactose (α-L-Fuc-(1,3)-D-Galß-1,4-Glu, 3'FL) with potential prebiotic effect were synthesized efficiently by a novel recombinant α-L-fucosidase. An α-L-fucosidase gene (PbFuc) from Pedobacter sp. CAU209 was successfully cloned and expressed in Escherichia coli (E. coli). The deduced amino acid sequence shared the highest identity of 36.8% with the amino sequences of other reported α-L-fucosidases. The purified α-L-fucosidase (PbFuc) had a molecular mass of 50 kDa. The enzyme exhibited specific activity (26.3 U/mg) towards 4-nitrophenyl-α-L-fucopyranoside (pNP-FUC), 3'FL (8.9 U/mg), and 2'FL (3.4 U/mg). It showed the highest activity at pH 5.0 and 35 °C, respectively. PbFuc catalyzed the synthesis of 3'FL and 2'FL through a transglycosylation reaction using pNP-FUC as donor and lactose as acceptor, and total conversion ratio was up to 85% at the optimized reaction conditions. The synthesized mixture of 2'FL and 3'FL promoted the growth of Lactobacillus delbrueckii subsp. bulgaricus NRRL B-548, L. casei subsp. casei NRRL B-1922, L. casei subsp. casei AS 1.2435, and Bifidobacterium longum NRRL B-41409. However, the growths of E. coli ATCC 11775, S. enterica AS 1.1552, L. monocytogenes CICC 21635, and S. aureus AS 1.1861 were not stimulated by the mixture of 2'FL and 3'FL. Overall, our findings suggest that PbFuc possesses a great potential for the specific synthesis of fucosylated compounds.Key Points• A novel α-L-fucosidase (PbFuc) from Pedobacter sp. was cloned and expressed.• PbFuc showed the highest hydrolysis activity at pH 5.0 and 35 °C, respectively.• It was used for synthesis of 3'-fucosyllactose (3'FL) and 2'-fucosyllactose (2'FL).• The mixture of 3'FL and 2'FL promoted the growth of some Lactobacillus sp. and Bifidobacteria sp.

Pedobacter schmidteae sp. nov., a new bacterium isolated from the microbiota of the planarian Schmidtea mediterranea.

Pedobacter schmidteae sp. nov. strain EGT (Collection de Souches de l'Unité des Rickettsie CSUR P6417 = Colección Española de Cultivos Tipo CECT 9771) is a new Pedobacter species isolated from the planarian Schmidtea mediterranea. Schmidtea mediterranea are flatworms living in freshwater and exhibiting an unusual ability to regenerate amputated parts. To date, the gut microbiota of Schmidtea mediterranea remains poorly studied. Here, via the culturomics strategy that consists in using diversified culture conditions, we isolated a new bacterium, strain EG, that we characterized using the taxono-genomics approach that combines phenotypic assays and genome sequencing and analysis. Strain EG exhibits a 16S rRNA sequence similarity of 98.29% with Pedobacter nyackensis strain NWG-II14T, its closest neighbour with standing in nomenclature. It is an aerobic bacterium belonging to the family Sphingobacteriaceae. Colonies are small, round, smooth and transparent. Bacterial cells are Gram-negative, rod-shaped, motile and non-spore-forming bacilli with positive catalase and oxidase activities. The genome sequence is 6,198,518 bp-long with a G + C content of 41.13%, and the Ortho-ANI and dDDH values when compared to P. nyackensis are 77.34% and 21.50%, respectively. Strain EGT exhibits unique characteristics that classify it as the type strain of new bacterial species for which we propose the name Pedobacter schmidteae sp. nov.

Bacteroidetes can be a rich source of novel lanthipeptides: The case study of Pedobacter lusitanus.

Lanthipeptides are intriguing peptides known since 1928, the year of penicillin's discovery. At that time, they were known as lantibiotics due to their (methyl)lanthionine amino acids and antibacterial activity. Their body of knowledge expanded tremendously over the last few years. Our analysis reveals that Bacteroidetes has a high state of clusters encoding the biosynthesis of class I lanthipeptides. We show that some strains of Pedobacter have a number of LanBs/genome comparable to that of some Actinobacteria. The case study selected was Pedobacter lusitanus NL19. Its clusters identified encode LanBs associated with LanCs as well as orphan LanBs. The first are concomitant with LanT transporters typical of class II lanthipeptides (and not class I), making their clusters into a hybrid class I and class II type. So far, this kind of operon was described only once and is involved in the production of pinensins, the first lanthipeptide with antifungal activity. A particular feature of pinensins is their splitted LanBs and we found that these enzymes are also widely encoded in Bacteroides. The function of a high percentage of proteins predicted to play a role in the production of Pedobacter lanthipeptides is unknown. Other major fraction of these proteins is expected to be enrolled in signal-transduction pathways. We demonstrate that the occurrence of lanthipeptides clusters in the genomes of Gram-negative bacteria is higher than previously reported. More importantly, we show that their genetic background is highly diverse, which is an undeniable foreshadowing of novel peptide structures, biochemistry and biological function.

Pedobacter indicus sp. nov., isolated from deep-sea sediment.

A Gram-stain negative, aerobic, non-flagellated, rod-shaped bacterium, designated strain SM1810T, was isolated from deep-sea sediment collected from the Southwest Indian Ocean. Strain SM1810T grows at 15-40 °C (optimum, 28 °C), at pH 5.0-9.0 (optimum, pH 6.0-7.0) and with 0-8% (w/v) NaCl (optimum, 1.5%). Phylogenetic analysis of 16S rRNA gene sequences revealed that strain SM1810T is affiliated with the genus Pedobacter, sharing high sequence similarity (95.8%) with the type strain of Pedobacter bauzanensis. The major fatty acids of strain SM1810T are iso-C15:0, summed feature 3 (C16:1ω7c and/or C16:1ω6c) and iso-C17:0 3OH. The predominant respiratory quinone is MK-7. The polar lipids are phosphatidylethanolamine, an unidentified aminophospholipid, an unidentified phospholipid and eight unidentified lipids. The genomic DNA G + C content of strain SM1810T was determined to be 40.8 mol%. Based on the phylogenetic, chemotaxonomic and phenotypic data obtained in this study, strain SM1810T is concluded to represent a novel species of the genus Pedobacter, for which the name Pedobacter indicus sp. nov. is proposed. The type strain is SM1810T (KCTC 62798T = CCTCC AB 2018198T).

Pedobacter changchengzhani sp. nov., isolated from soil of Antarctica.

A Gram-negative, aerobic, non-motile, pink and rod-shaped bacterium, designated E01020T, was isolated from soil collected from the Chinese Great Wall Station, Antarctica. Comparative analysis of 16S rRNA gene sequences revealed that strain E01020T is a member of the genus Pedobacter, related to Pedobacter alluvionis DSM 19624T (96.8% similarity), Pedobacter agri JCM 15120T (96.5% similarity) and Pedobacter chinensis JDX94T (96.3% similarity). The dDDH values and ANI values of strain E01020T with closely related strains indicate that it can be distinguished from them as a novel species. The DNA G+C content was determined to be 35.2 mol%. The growth of strain E01020T was observed at 4-25 °C (optimal 20 °C), in the presence of 0-1% NaCl (w/v, optimal 0%) and at pH 6.0-8.0 (optimal pH 7.0). Strain E01020T was found to contained menaquinon-7 (MK-7) as only respiratory quinone, iso-C15:0, iso-C17:0 3-OH and Summed feature 3 (C16:1ω6c and/or C16:1ω7c) as major fatty acids. The major polar lipids were phosphatidylethanolamine, one unidentified lipid and two unidentified aminolipids. On the basis of the results of the phylogenetic and phenotypic analyses, it was suggested that strain E01020T represents a novel species of the genus Pedobacter, for which the name Pedobacter changchengzhani sp. nov. is proposed. The type strain is E01020T (= KCTC 62990T = MCCC 1H00357T).

Proposal of Pedobacter nototheniae sp. nov., isolated from the spleen of a black rock cod (Notothenia coriiceps, Richardson 1844) from the Chilean Antarctica.

A pink pigmented, Gram-negative, rod-shaped, non-spore-forming bacterium (strain 36B243T), was isolated from the spleen of a black rock cod (Notothenia coriiceps, Richardson 1844) in the Chilean Antarctica. Strain 36B243T has a 5.26 Mb chromosome with a DNA G + C content of 35.4 mol%. The draft genome includes the prediction and annotation of 4585 coding genes, and 46 tRNA, 1 tmRNA, and 2735 hypothetical proteins. Phylogenetic analysis based on the 16S rRNA gene sequence placed strain 36B243T into the genus Pedobacter with high sequence similarity to the type strains of Pedobacter sandarakinus (97.5%) and Pedobacter petrophilus (97.1%). Sequence similarities to type strains of all other current Pedobacter species were below 97.1%. Predominant fatty acids are summed feature 3 (C16:1ω7c and/or C16:1ω6c) and iso-C15:0 followed by iso-C17:0 3-OH and C16:0. The major respiratory quinone was menaquinone MK-7. The polar lipid profile contained the major lipids phosphatidylethanolamine, five unidentified aminolipids, two lipids lacking a functional group and two minor glycolipids and one lipid lacking a functional group. An alkali-stable lipid was present. The polyamine pattern contained the predominant compound sym-homospermidine. Characterization by 16S rRNA gene sequence analysis, physiological parameters, pigment analysis, ubiquinone, polar lipid, and fatty acid composition revealed that strain 36B243T represents a new species of the genus Pedobacter. For this reason, we propose the name Pedobacter nototheniae sp. nov. with the type strain 36B243T (= LMG 30634T = CCM 8855T = CIP 111622T).

Pedobacter paludis sp. nov., isolated from wetland soil.

A Gram-stain-negative, aerobic, non-motile, rod-shaped and non-spore-forming bacterium, designated YXT, was isolated from wetland soil. Compared to strain YXT, Pedobacter yonginense HMD1002T had the highest 16S rRNA gene sequence identity (97.8%), and the remaining strains had the identities below 97%. Phylogenetic analysis of the 16S rRNA gene sequences showed that strain YXT grouped with P. yonginense HMD1002T. The values of DNA-DNA hybridization and genomic orthologous average nucleotide identity (orthoANI) between strain YXT and Pedobacter yonginense KCTC 22721T were 58.5% and 82.0%, respectively. The genome size of strain YXT was 5.0 Mb, comprising 4369 predicted genes with a DNA G+C content of 37.3 mol %. Strain YXT had menaquinone-7 as the only respiratory quinone and polar lipids of phosphatidylethanolamine, sphingolipid, aminolipid and three unidentified lipids. The predominant cellular fatty acids (> 10%) of strain YXT were summed feature 3 (iso-C15:0 2-OH and/or C16:1ω7c), iso-C15:0 and iso-C17:0 3-OH. Strain YXT could be distinguished from the other Pedobacter members based on the data of phylogenetic distance, DNA-DNA hybridization, genomic orthoANI, RecA MLSA, core-protein comparison, and hydrolyses of L-arginine, utilization of D/L-lactate, L-alanine, 5-ketonic gluconate and glycogen. Therefore, strain YXT represents a novel species of the genus Pedobacter, for which the name Pedobacter paludis sp. nov. is proposed. The type strain is YXT (= KCTC 62520T = CCTCC AB 2018029T).

Pedobacter chitinilyticus sp. nov., a chitin-degrading bacterium isolated from wheat leaf tissue.

A bacterium, designated strain CM134L-2T, was isolated from a chitin-enriched wheat leaf microbiome in Chengdu, Sichuan province, China. It was Gram-stain-negative, strictly aerobic, non-spore-forming, motile, rod-shaped, and bright yellow in colour. Strain CM134L-2T grew at 4-35 °C, at pH 6.0-9.0 and could use chitin as the only carbon resource. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain CM134L-2T was most closely related to Pedobacter nanyangensis Q-4T (97.7 %) and Pedobacter zeaxanthinifaciens TDMA-5T (97.4 %). Digital DNA-DNA hybridization (dDDH) values between strain CM134L-2T with these two type strains were 26.8  and 20.8 %, respectively, and average nucleotide identity (ANI) values were 83.2 and 76.2 %; these values are lower than the proposed and generally accepted species boundaries of 70 % for dDDH and 95-96 % for ANI, which suggests strain CM134L-2T represents a novel species. The genomic DNA G+C content of strain CM134L-2T was 39.3 mol%, menaquinone-7 was the major respiratory quinone, phosphatidylethanolamine was the major polar lipid and the major components of the cellular fatty acids were iso-C15 : 0, and C16 : 1ω7c/C16 : 1ω6c (summed feature 3); these features supported the affiliation of strain CM134L-2T to the genus Pedobacter. Overall, strain CM134L-2T belongs to the genus Pedobacter, but can be classified as a novel species, for which the name Pedobacter chitinilyticus sp. nov. is proposed. The type strain is CM134L-2T (=CGMCC 1.16520T=KCTC 62643T).

Pedobacter yulinensis sp. nov., isolated from sandy soil, and emended description of the genus Pedobacter.

A Gram-staining-negative, rod-shaped, strictly aerobic, non-motile, non-spore-forming, orange bacterium, which was designated strain YL28-9T, was isolated from sandy soil in the district of Yulin, Shaanxi province, PR China, and was characterized by using a polyphasic taxonomic approach. The optimal growth conditions of the strain were 30 °C, pH 7.0, 0 % (w/v) NaCl. Phylogenetic analysis, based on the 16S rRNA gene sequence, revealed that YL28-9T represented a member of the genus Pedobacter and showed the highest sequence similarity to Pedobacter rhizosphaeraeKACC 14938T (95.1 %). The genomic DNA G+C content of this strain was 50.4 mol%, which was out of the range reported for the other strains of members of the genus Pedobacter. The only respiratory quinone detected in YL28-9T was menaquinone-7 (MK-7). The predominant cellular fatty acids were identified as iso-C15 : 0, summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and iso-C17 : 0 3-OH. The major polar lipid was phosphatidylethanolamine. On the basis of the results of phenotypic, genotypic, chemotaxonomic and phylogenetic analysis, YL28-9T could be distinguished from the most closely related species of the genus Pedobacter. It is evident from the derived data that YL28-9T represents a novel species of the genus Pedobacter,for which the name Pedobacter yulinensis sp. nov. is proposed. The type strain is YL28-9T (=CGMCC 1.16050T=KCTC 62104T). An emended description of the genus Pedobacteris proposed.

Pedobacter aquicola sp. nov., isolated from freshwater.

A non-motile, pink-pigmented bacterial strain designated IMCC25679T, was isolated from freshwater Lake Chungju of Korea. Phylogenetic trees based on 16S rRNA gene sequences showed that the strain IMCC25679T formed a lineage within the genus Pedobacter. The strain IMCC25679T was closely related to Pedobacter daechungensis Dae 13T (96.4% sequence similarity), Pedobacter rivuli HME8457T (95.3%) and Pedobacter lentus DS-40T (94.3%). The major fatty acids of IMCC- 25679T were iso-C15:0, iso-C16:0 and summed feature 3 (comprising C16:1ω6c and/or C16:1ω7c). The major respiratory quinone was MK-7. The major polar lipids were phosphatidylethanolamine (PE), an unidentified sphingolipid (SL), an unidentified aminolipid (AL) and three unidentified polar lipids (PL). The DNA G + C content of IMCC25679T was 32.2 mol%. Based on the evidence presented in this study, the strain IMCC25679T represents a novel species within the genus Pedobacter, with the proposed name Pedobacter aquicola, sp. nov. The type strain is IMCC25679T (= KACC 19486T = NBRC113131T).