The samples that contained parts of diseased walnut branches and trunks showing symptoms of deep bark canker and longitudinal oozing cracks ( Figures 1 , 2 ) were collected in orchards in the north part of Serbia in the late summer (September, 2020). Bacterial isolation was carried out from several sections of the symptomatic walnut tissue. Briefly, fresh fragments from border area between apparently healthy and diseased tissue under the bark and deeper in the region of the xylem, were macerated in 1 ml of sterile distilled water (SDW). The macerate was incubated at room temperature for 10 min and streaked onto King’s medium B (KB) (King et al., 1954), followed by incubation at 27°C. The sapwood samples found in small cracks were also used for isolation on KB medium. After 3 days, bacterial colonies were purified and maintained on KB medium for further testing. Long-term storage of bacterial isolates was achieved at -80°C in a mixture of nutrient broth medium and 30% glycerol (Schaad et al., 2001).

Sources of bacterial strains used within this study, including reference strains, are listed in Table 1 and Table S1 .

In order to identify and characterize isolates, various physiological and biochemical tests were performed. They were tested for Gram reaction using 3% KOH, catalase activity, fluorescence on KB, oxidative–fermentative (O/F) test, oxidase activity, levan production, pectinolytic activity on potato slices and production of a hypersensitive reaction (HR) on tobacco (Nicotiana tabacum cv. ‘Samsun’) and geranium (Pelargonium x hortorum) leaves (Lelliott and Stead, 1987). The isolates were grown on different media such as KB, Yeast extract - Dextrose-Calcium carbonate agar (YDC), Yeast-Peptone-Glucose Agar (YPGA), Nutrient Agar supplemented with 5% sucrose w/v (NSA) (Schaad et al., 2001) Additional biochemical and physiological analyses of seven walnut isolates (KBI 423^T, KBI 424, KBI 429, KBI 430, KBI 447, KBI 446 and KBI 449), including two reference strains LMG 2709^T of Brenneria salicis (Bs) and LMG 2698^T of Br, were conducted using the API 20E, API 20NE, and API 50CH systems (bioMérieux). For API 20E and API 20NE, the pure bacterial cultures grown on KB medium for 24 h were suspended in 0.85% NaCl solution. Concentration of bacterial suspensions was adjusted to ~10⁸ CFU/ml photometrically (OD₆₀₀ = 0.3). Further, the test strips were handled by following manufacturer instructions. For API 50CH, the bacteria were suspended in API 50 CHB/E medium (bioMérieux) in the same concentration. API strips were incubated at 27°C for 48 h (Biosca and López, 2012). Obtained results were compared with data available in the literature (Brady et al., 2012; Brady et al., 2014). All API tests were conducted in three replicates.

Pathogenicity of the isolates was assessed by inoculating two-year-old walnut plants cv. Chandler grown in pots, by method of Moretti et al. (2007), with slight modifications. Six Brenneria isolates (KBI 423^T, KBI 424, KBI 429, KBI 446, KBI 447 and KBI 449) and one isolate of Xaj (KBI 435) were selected for testing. The plants were inoculated by infiltration of 20 µl of bacterial suspension (~10⁸ CFU/ml, OD₆₀₀ = 0.3) into 2-cm-long vertical stem wounds made aseptically by a scalpel. Two plants with three wounds (inoculation points), per each strain were inoculated. SDW was used as a negative control. Inoculated tissue was covered by wet cotton pad and wrapped with a Parafilm tape for four days to prevent drying out. One month post-inoculation, new, young saplings (shoots) were developed on the test plants. They were also inoculated by above described method with a slight modification – 1 cm longitudinal wound was made by scalpel and there were two inoculation sites per plant. Test plants were maintained in the greenhouse for 2 months. Afterwards, the pots were moved outside and observed for the next 14 months. The appearance of external and internal symptoms was recorded two and 14 months post-inoculation. Re-isolation of bacteria from inoculated plants (two and 14 months post-inoculation) was performed on KB medium and their identity was confirmed by PCR assay.

Additionally, pathogenicity of the representative isolates (KBI 423^T, KBI 446 and KBI 435) was tested on immature walnut fruits prior to crust hardening. After surface sterilization with 70% alcohol, the fruits were injured on three sites by sterile tip and inoculated with 30 µl of tested bacterial suspension (~10⁸ CFU/ml). The test was performed in three replications. The reference strain of Bn KBI 024 (Popovic et al., 2013), type strains LMG 2709^T of Br and LMG 2698^T of Bs, were used as controls. SDW was used as a negative control. The fruits were placed in a sterile, humid, plastic chamber and incubated at 27°C for 15 days in dark conditions. Bacteria were re-isolated on KB and their identity was confirmed by PCR assay.

Total genomic DNA was extracted from pure bacterial cultures using the cetyl trimethyl ammonium bromide (CTAB) protocol, according to the instructions described by Angelini et al. (2001), with slight modifications. Bacterial suspensions (~10⁹ CFU/ml) were prepared in 500 µl 10 mM phosphate saline buffer (Na₂HPO₄ × 12 H₂O 2.7 g/l, NaH₂PO₄ × 2 H₂O 0.4 g/l). Afterwards, 500 µl extraction buffer (3% CTAB, 1M Tris-HCL pH 8.0, 1.4 M NaCl, 20 mM EDTA, 3% PVP) was added in the equal volume of bacterial suspensions and incubated at 65°C for 20 min. The following steps were as described in original protocol.

For whole-genome sequencing, DNA of isolates KBI 423^T and KBI 447 was extracted using the DNeasy Plant Mini Kit (Qiagen, Hilden, Germany). The quality of extracted DNA was checked by gel electrophoresis on 0.8% agarose gel and then stored at −20°C for further analysis.

Based on host plant, disease symptoms and colony morphology, we assumed that causal agents of infection might belong to genera Brenneria and/or Xanthomonas. Therefore, three PCR reactions were performed by using: Bn-specific primers F1/C3 (Loreti et al., 2008); primer pair BR1/BR3 specific for Br (McClean et al., 2008) and XajF/XajR primers specific for Xaj (Gironde et al., 2009). Additionaly, we applied a PCR with primers Es1A/Es4B, specific for Bs (Hauben et al., 1998). Amplified PCR products (5 µL) were separated by gel electrophoresis in 1.5% agarose gel in 0.5 × Tris-Borate-EDTA (TBE) buffer stained with 2% (v/v) Midori Green (MIDORI Green Advance, NIPPON Genetics EUROPE) and visualized by a digital imaging camera (Vilber Lourmat, France). All primers sequences used in this study are shown in Table S2 .

The 16S rRNA and housekeeping gene fragments were amplified and sequenced (Macrogene Europe, The Netherlands) for several representative strains. The partial sequence of 16S rDNA of strains KBI 423^T, KBI 424, KBI 428 and KBI 429 was amplified using universal pair of primers fD1 and rP2 (Weisburg et al., 1991). Four representative Brenneria strains (KBI 423^T, KBI 429, KBI 430 and KBI 447) belonging to the unknown species were selected for multilocus sequence analysis (MLSA). PCR amplification and partial sequencing of four housekeeping genes, atpD, gyrB, infB, and rpoB, was conducted according to the protocol of Brady et al. (2008).

Chromatograms were visualized using FinchTV 1.4.0 software and sequences were processed using the MEGA 7 package (Kumar et al., 2016). In order to align the sequences, CLUSTAL W algorithm (Higgins et al., 1996) integrated into MEGA 7 software (Kumar et al., 2016) was used. For comparative analysis of the obtained sequences with the sequences deposited in the NIH GenBank, the BLASTn program was used (Altschul et al., 1997). The maximum likelihood (ML) phylogenies based on 16S rDNA and concatenated sequences of housekeeping genes were inferred using IQ-TREE 1.6.12 (Nguyen et al., 2015) software available through the IQ-TREE web server ³ (Trifinopoulos et al., 2016). A model selection was conducted using IQ-TREE ModelFinder (Kalyaanamoorthy et al., 2017). The best-fit DNA substitution models HKY+F+I+G4 (16S rDNA) and TIM2+F+I+G4 (housekeeping genes, concatenated dataset) were selected based on Bayesian Information Criterion (BIC). Branch support was assessed by ultrafast bootstrap analysis (UFBoot) using 1000 replicates (Hoang et al., 2018). The tree was visualized using FigTree, v1.4.4 ⁴ (Rambaut, 2018).

Genetic relatedness among the strains was evaluated by rep-PCR fingerprinting. Seventeen Brenneria spp. isolates recovered within this study were amplified in three PCR reactions by BOXA1R, REP1R-I/REP2-I and ERIC1R/ERIC2 primers (Versalovic et al., 1991; Versalovic et al., 1994). Amplified fragments were separated by gel electrophoresis in 1.5% agarose gel in 0.5 × TBE buffer and visualized as described above.

Whole-genome sequencing was conducted for two Brenneria isolates, KBI 423^T and KBI 447. The library preparation, sequencing and initial processing of reads was performed by Novogene, Cambridge, United Kingdom. The genomic DNA was randomly sheared into short fragments (~350bp). DNA libraries were prepared with NEBNext Ultra II DNA Library Prep Kit for Illumina (New England Biolabs). Sequencing was performed on Illumina NovaSeq PE150 platform. A total of 2×8,784,885 and 2×8,152,797 paired-end reads were generated for strains KBI 423^T and KBI 447, respectively. Furthermore, adapter trimming and quality filtering of raw reads were conducted with Cutadapt ver. 3.7 (Martin, 2011). De novo sequence assembly was performed using SPAdes 3.15.3 (with options -k 21,33,55,77 and –isolate) (Prjibelski et al., 2020). Short (<200 bp) and low-coverage (<3-fold) contigs were discarded. Furthermore, the Illumina reads were mapped to the remaining contigs with BWA-MEM (Galaxy Version 0.7.17.2) (Li, 2013), to manually curate assemblies, involving correction of sequence errors and mis-assemblies. The genome sequences were annotated using Prokka (Galaxy Version 1.14.6+galaxy1) (Seemann, 2014) and NCBI Prokaryotic Genomes Annotation Pipeline (PGAP) (Tatusova et al., 2016).

Core-genome phylogeny was inferred using the GET_HOMOLOGUES Version 11042019 (Contreras-Moreira and Vinuesa, 2013) and GET_PHYLOMARKERS Version 2.2.8_18Nov2018 (Vinuesa et al., 2018) software packages as described before (Kuzmanović et al., 2022). The dataset contained two strains studied (KBI 423^T and KBI 447), as well as reference strains of Brenneria (14 strains), Dickeya (3 strains), Lonsdalea (3 strains) and Pectobacterium (3 strains). As an outgroup, we used members of the family Erwiniaceae, including Erwinia spp. (4 strains) and Pantoea spp. (4 strains) ( Table S3 ).

The species delineation was assessed by different overall genome relatedness indices (OGRIs), including the average nucleotide identity (ANI) (Goris et al., 2007) and digital DNA-DNA hybridization (dDDH) (Meier-Kolthoff et al., 2013). The ANI calculations were performed using PyANI program Version 0.2.11, with scripts employing BLAST+ (ANIb) and MUMmer (ANIm) algorithm to align the input sequences ⁵ (Pritchard et al., 2016), and OrthoANIu Version 1.2 (calculates orthologous ANI using USEARCH algorithm) (Yoon et al., 2017). The dDDH values were computed by the Genome-to-Genome Distance Calculator (GGDC 2.1) ⁶ using the recommended BLAST+ alignment and formula 2 (identities/HSP length) (Meier-Kolthoff et al., 2013).

For molecular detection, identification and differentiation of novel Brenneria strains characterized in this study, we developed a specific PCR assay. Specific primers were designed based on the sequence of the putative gene hrpP (locus_tag=“NC856_01210” in assembly referring to strain KBI 423^T) coding for type III secretion system HrpP C-terminal domain-containing protein. Candidate primers were identified at nucleotide positions 90–114 and 407–429 and were designated Bi-hrpP-F (5′-TGATAGCTTTTGGGAAGAGTTCGCT-3′) and Bi-hrpP-R (5′-ACAGGATTCACGCCGATCTTTCA-3′), respectively. The PrimerQuest tool by Integrated DNA technologies (IDT) was used to design primers (Integrated DNA Technologies, Coralville, IA). The size of the amplification product is 340 bp. Specificity of the primer set was tested with 46 strains ( Table S1 ) and additionally checked in silico by performing NCBI Primer-BLAST against the non-redundant (nr) and “Refseq representative genomes” databases ⁷ .

The PCR amplifications were performed in a 15 μl mixture containing: 1 × Color OptiTaq PCR Master Mix (EURx, Gdańsk, Poland) (1.25 U OptiTaq DNA Polymerase; 1× Reaction Buffer with 1.5 mM MgCl₂; 0.2 mM of each dNTP), 0.5 μM of each primer and 1.5 µl template DNA. The thermal profile was as follows: initial denaturation at 95˚C for 2 min, 35 cycles of denaturation at 95˚C for 30 s, annealing at 60˚C for 30 s, elongation at 72˚C for 30 s, and final extension at 72˚C for 5 min. Reaction were performed in a Thermal Cycler 2720 (Applied Biosystems, Foster City, CA, USA).

The GenBank accession numbers for the partial 16S rRNA gene sequences of the Brenneria strains KBI 423T, KBI 424, KBI 428 and KBI 429 are MW485945 to MW485948, respectively. Generated (Table S3) partial sequences of housekeeping genes for Brenneria strains KBI 447, KBI 430, KBI 429, KBI 423T, were deposited in the NIH GenBank database under accession numbers ON228202 to ON228205 for atpD gene, ON638957 to ON638960 for infB, ON638961 to ON638964 for gyrB and ON638965 to ON638968 for rpoB, respectively (Table S3).

The Whole Genome Shotgun projects have been deposited at DDBJ/ENA/GenBankunder the accessions JAMPJT000000000 (KBI 447) and JAMPJU000000000 (KBI 423T); within the BioProject PRJNA832546. The versions described in this paper are the first versions, JAMPJT010000000 and JAMPJU010000000. The raw sequencing reads were deposited in the Sequence Read Archive (SRA) under the same BioProject PRJNA832546.

Bacterial strains were isolated from the symptomatic walnut samples collected in two localities in the northern part of Serbia. After 2 to 3 days of incubation at 27°C on KB medium, two major types of colonies were observed. Light cream, circular and smooth colonies with entire margins were predominant on the KB plates. The second group consisted of small, yellowish, circular and convex colonies resembling Xanthomonas species. The former strains were Gram- and oxidase negative, facultatively anaerobic, levan positive, nonfluorescent, and did not produce bright-red pigment on YDC and YPGA medium. Seventeen tested isolates showed phenotypic characteristics as described for type Brenneria spp. ( Table 1 ) (Brady et al., 2012). In particular, they showed no pectinolytic activity on potato slices. They did not induce hypersensitive reaction on tobacco leaves but induced HR reaction on geranium 24 h after inoculation. Strains KBI 446 and KBI 449 did not induce HR response in any test plant. No symptoms were observed on tissue inoculated with SDW.

Seven representative strains were selected for further analysis by API 20E, API 20NE, and API 50CH tests and compared with strain LMG 2698^T of Bs, LMG 2709^T of Br, as well as literature data for B. goodwinii, B. alni, B. rosae subsp. rosae and Lonsdalea quercina (Brady et al., 2012; Brady et al., 2014). Five representative strains (KBI 423^T, KBI 424, KBI 429, KBI 430 and KBI 447) showed phenotypic traits as follow: positive reactions for acid production from L-arabinose, D-galactose, inositol, melibiose, raffinose, potassium gluconate, glycerol, and negative reactions from gentiobiose, D-sorbitol, trehalose, turanose, amygdalin and D-xylose ( Table 2 ). The obtained results were compared with features already determined for other Brenneria species (Brady et al., 2012), and we found that these strains showed unique characteristics as they did not fit into any already existing profile. Two remaining strains (KBI 446 and KBI 449) produced acid from L-arabinose, gentiobiose, inositol, melibiose, raffinose, D-sorbitol, trehalose, glycerol and D-xylose and showed negative reaction for amygdalin, indol, turanose, D-galactose, and potassium gluconate. These two strains had identical features as Bn previously described (Brady et al., 2012) ( Table 2 ).

Eleven Xanthomonas-like isolates belonging to the second group were aerobic, Gram- and oxidase negative, catalase positive, forming yellow, round, mucoid and convex colonies on YPGA medium after 3 days of incubation at 27°C. These strains induced HR reaction on both, tobacco and geranium leaves.

In pathogenicity assay, extensive stem tissue necrosis developed around the point of inoculation of walnut plants two months after inoculation with the novel Brenneria strains KBI 423^T, KBI 424, KBI 429 and KBI 447. Necrotic lesions were also observed in the inner bark tissue ( Figure S1A ). Lesions extended from the site of inoculation and small longitudinal cracks in the bark were formed. After bark removal, brown necrotic streaks extending deeper into the xylem were visible. After 14 months, the necrotic tissue under the bark of inoculated stems extended to 8 cm in length ( Figure S1B ). However, external cankers like those observed under natural conditions as well as oozing of a dark liquid from the wounds were not observed. Additionally, severe symptoms of deep tissue necrosis around the point of inoculation were observed on young branches three weeks after inoculation ( Figure S1C ). After removing the surface tissue, lesions appeared as longitudinal blackish streaks that extended deeper into inner tissue. Symptoms of internal necrosis were also observed in the plants inoculated with strains KBI 446 and KBI 449 of Bn. Strain KBI 435 of Xaj caused limited necrosis of stem and shoots tissue at point of inoculation. From all inoculated plants, bacteria were re-isolated on KB medium from the lesions on the stem and branches, respectively two and 14 months after inoculation. Identity of the strains was confirmed by specific PCR tests. Symptoms of necrosis did not develop on control plants, and we did not isolate any bacteria from the inner tissue.

In addition, characteristic symptoms of necrosis and sunken black lesions around the point of inoculation and deeper in the inner tissue were observed on young walnut fruits 14 days after inoculation with strains KBI 423^T, KBI 446 and KBI 435. Three weeks after inoculation, bacteria were re-isolated on KB and their identity was confirmed by specific PCR assays, described below. No symptoms developed on control fruits inoculated with Bs and SDW.

Different PCR assays were applied in order to identify isolates. Seventeen isolates of Brenneria sp. were PCR tested by using primers specific to Bn, Br and Bs. In PCR assay using primers Es1A/Es4B specific for Bs, a 553 bp DNA fragment was amplified in fifteen isolates ( Table 1 ). PCR reaction with F1/C3 primers yielded specific 250 bp product in two remaining isolates (KBI 446 and KBI 449), indicating their affiliation to Bn species. Primers specific for Br did not amplify expected 409 bp fragment in any tested isolate. Identity of yellowish, small, circular colonies as Xaj was confirmed by using XajF/XajR primers amplifying specific 216 bp fragment ( Table 1 ).

The obtained genetic PCR profiles showed that the 15 novel Brenneria isolates represent a homogenous group, by using BOXА1R, ERIC1R/ERIC2 and REP1R-I/REP2-I primers. The isolates formed a unique fingerprint profile that differs from the profiles of Bn, Br and Bs used in the analysis (data not shown). Moreover, two Bn isolates showed an identical profile to the Bn reference strain KBI 024.

The partial 16S rRNA gene sequences of the novel Brenneria strains were identical, and showed highest nucleotide identity (98.42%) to the sequence of Bs type strain LMG 2698^T (Acc. No. AJ233419). Indeed, phylogenetic analysis based on 16S rDNA sequences also indicated that strains KBI 423^T, KBI 424, KBI 428 and KBI 429 were most closely related to Bs ( Figure 3 ), although they formed a separate phylogenetic lineage within the genus Brenneria. Moreover, 16S rDNA phylogeny indicated that the genus Brenneria is polyphyletic, as it was intertwined with Lonsdalea spp. ( Figure 3 ).

Partial sequences of atpD, gyrB, infB and rpoB genes were obtained for four novel Brenneria isolates (KBI 423^T, KBI 429, KBI 430 and KBI 447). Strains studied exhibited identical sequences for each of the four housekeeping genes. Phylogenetic trees were generated based on the sequence of each gene (data not shown), as well as on concatenated datasets of four housekeeping genes ( Figure 4 ). In all phylogenetic trees, novel Brenneria strains formed a separate clade with 100% bootstrap support, with Bs located on an adjacent branch. In the phylogenetic tree generated from concatenated dataset, they clustered within the Brenneria clade B defined previously by Bakhshi Ganje et al. (2021) ( Figure 4 ). Similarly as for 16S rRNA gene phylogeny, polyphyly of the genus Brenneria was evident in the MLSA tree. In particular, Brenneria clades A and B were separated by Pectobacterium strains included in the analysis ( Figure 4 ).

Draft genome sequences of strains KBI 423^T and KBI 447 were obtained in this study ( Table 3 ). The de novo assembly resulted in 66 (KBI 423^T) and 62 (KBI 447) contigs. The genome coverage was 638- (KBI 423^T) and 592-fold (KBI 447). The draft genome sequence of strain KBI 423^T consisted of 3,896,770 bp, with an average G+C content of 51.76%, while that of strain KBI 447 consisted of 3,897,516 bp, with an average G+C content of 51.76%. Other general features of draft genome sequences are sumarized in Table 3 .

A core-genome phylogenetic tree was reconstructed from the supermatrix obtained by concatenation of 663 top gene markers. Strains KBI 423^T and KBI 447 formed a separate cluster within the genus Brenneria, within the clade B defined previously by Bakhshi Ganje et al. (2021) ( Figure 5 ). As indicated by 16S rRNA and housekeeping gene phylogenetic analyses, core-genome phylogeny confirmed that their closest relative was Bs strain LMG 2698^T ( Figure 5 ). Core-genome phylogeny indicated monophyly of the genus Brenneria, with two well-separated clades A and B.

OGRIs computed ( Table S4 ) revealed that KBI 423^T and KBI 447 represent a new Brenneria species, closely related to Bs. In particular, they shared 94.48% (ANIb), 94.68% (ANIm), 94.51% (orthoANIu) and 57.8% (dDDH) overall genome relatedness with the type strain of Bs (LMG 2698^T), which was below the proposed thresholds for species delineation (95–96% for ANI, and 70% for DDH) ( Table S4 ). Obtained OGRIs were relatively low when KBI 423^T and KBI 447 were compared with other Brenneria spp. (<87% for ANI, <31 for dDDH). A description of the novel Brenneria species, for which the name Brenneria izbisi sp. nov. is proposed, is given below.

Genomic DNA of B. izbisi sp. nov. was amplified by using a conventional PCR assay with specific primers designed in this study. Using primers Bi-hrpP-F/Bi-hrpP-R, all tested strains of this species yielded the expected 340 bp amplicon. Contrarily, there was no amplification of DNA from the other 31 strains belonging to different species with this primer set ( Table S1 ). Moreover, Primer-BLAST analysis against the nr database confirmed that the specificity of primers Bi-hrpP-F/Bi-hrpP-R is restricted to B. izbisi.

Brenneria izbisi (iz.bi‘si. N.L. gen. n. izbisi, of IZBIS [Institut za zaštitu bilja i životnu sredinu, eng. Institute for Plant Protection and Environment], where this taxonomic study was performed).

Bacterial cells are Gram-negative and oxidase-negative, facultatively anaerobic, levan positive, nonfluorescent, and do not produce bright-red pigment on YDC and YPGA medium. The strains showed no pectinolytic activity on potato slices. They do not induce hypersensitive reaction on tobacco leaves but induced response on geranium plants. Positive for fermentation of glycerol, L-arabinose, D-ribose, D-galactose, D-glucose, D-fructose, D-mannose, L-rhamnose, inositol, D-manitol, methyl-α-D-glucopyranoside, N-acetylglucosamine, arbutine, esculine, salicin, D-melibiose, D-saccharose, D-rafinose, potassium gluconate and negative for erythritol, D-arabinose, D-xylose, L-xylose, D-adonitol, methyl-β-D-xylopiranoside, L-sorbose, dulcitol, D-sorbitol, methyl-α-D-mannopyranoside, amygdalin, D-celobiose, D-maltose, D-lactose, D-trehalose, inulin, D-melezitose, starch, glycogen, xylitol, gentiobiose, D-turanose, D-lyxose, D-tagatose, D-fucose, L-fucose, D-arabitol, L-arabitol, potassium 2-ketogluconate and potassium 5-ketogluconate (API 50 CHB/E). Nitrate is not reduced to nitrite, nor reduced to N₂ gas. The strains do not produce indole, gelatinase, urease or acetoin but assimilate potassium gluconate and produce acid from glycerol.

The genomic G+C content of the type strain is 51.8 mol%. Its approximate genome size is 3.9 Mbp.

B. izbisi can be distinguished from other Brenneria spp. based on OGRIs (e.g. ANI and dDDH) and core-genome phylogeny, as well as by analysis of sequences of housekeeping genes. In addition, it showed unique phenotypic features, comparing with other Brenneria species.

The type strain, KBI 423^T (= CFBP 9035^T = LMG 32479^T) was isolated from walnut trees in Serbia in 2020. Whole-genome shotgun sequence of the strain KBI 423^T has been deposited at the NIH GenBank under the accession number JAMPJU000000000.