Flavobacterium acetivorans sp. nov. and Flavobacterium galactosidilyticum sp. nov., psychrotolerant flavobacteria isolated from cultivated fish.

Two yellow-coloured strains, F-29T and F-340T, were isolated from fish farms in Antalya and Mugla in 2015 and 2017 during surveillance studies. The 16S rRNA gene sequence analysis showed that both strains belong to the genus Flavobacterium. A polyphasic approach involving a comprehensive genome analysis was employed to ascertain the taxonomic provenance of the strains. The overall genome-relatedness indices of digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) between the strains and the other members of the genus Flavobacterium were found to be well below the established thresholds of 70 and 95 %, respectively. The whole-genome-based phylogenetic analysis revealed that strain F-29T is closely related to Flavobacterium granuli (dDDH 39.3 % and ANI 89.4 %), while strain F-340T has a close relationship with the type strain of Flavobacterium pygoscelis (dDDH 25.6 % and ANI 81.5 %). Both strains were psychrotolerant with an optimum growth temperature of 25 °C. The chemotaxonomic characteristics of the strains were typical of the genus Flavobacterium. Both strains had phosphatidylethanolamine, aminolipids and unidentified lipids in their polar lipid profile and MK-6 as the isoprenoid quinone. The major fatty acids were iso-C15 : 0 and anteiso-C15 : 0. The genome size of the strains was 3.5 Mb, while G+C contents were 35.3 mol% for strain F-29T and 33.4 mol% for strain F-340T. Overall, the characterizations confirmed that both strains are representatives of two novel species within the genus Flavobacterium, for which the names Flavobacterium acetivorans sp. nov. and Flavobacterium galactosidilyticum sp. nov. are proposed, with F-29T (JCM 34193T=KCTC 82253T) and F-340T (JCM 34203T=KCTC 82263T) as the type strains, respectively.

A Review of the Industrial Importance, Common Bacterial Diseases, and Zoonotic Risks of Freshwater Aquarium Fish.

Background: The ever-increasing popularity of home aquariums, most often involving freshwater varieties, has exploded in recent years partially due to the Coronavirus pandemic and related to stay-at-home public health precautions for social distancing. With this ever-increasing popularity of aquariums as a hobby, and whether this involves freshwater or marine fish species, a number of important economic, ecological, and public health issues arise for both fish and hobbyists alike. Materials and Methods: This review highlights the history and genesis of aquariums as both a hobby and an important economic factor (industrial, commercial) for many countries on a global basis. Types of aquarium fish are described, and culture conditions leading to homeostasis in aquatic environments are detailed. When these conditions are not met and aquatic systems are out of balance, the disease can result due to stressed fish. Results: Major bacterial diseases associated with freshwater aquarium fish are reviewed, as are potential human infections related to the care and maintenance of home aquaria. Conclusion: Besides, scientific information was also combined with the false facts of hobbyists who tried to identify and treat diseases during an outbreak in the aquarium. Finally, unresolved issues and important misconceptions regarding the field are discussed.

A review of bacterial disease outbreaks in rainbow trout (Oncorhynchus mykiss) reported from 2010 to 2022.

Outbreaks of bacterial infections in aquaculture have emerged as significant threats to the sustainable production of rainbow trout (Oncorhynchus mykiss) worldwide. Understanding the dynamics of these outbreaks and the bacteria involved is crucial for implementing effective management strategies. This comprehensive review presents an update on outbreaks of bacteria isolated from rainbow trout reported between 2010 and 2022. A systematic literature survey was conducted to identify relevant studies reporting bacterial outbreaks in rainbow trout during the specified time frame. More than 150 published studies in PubMed, Web of Science, Scopus, Google Scholar and relevant databases met the inclusion criteria, encompassing diverse geographical regions and aquaculture systems. The main bacterial pathogens implicated in the outbreaks belong to both gram-negative, namely Chryseobacterium, Citrobacter, Deefgea Flavobacterium, Janthinobacterium, Plesiomonas, Pseudomonas, Shewanella, and gram-positive genera, including Lactococcus and Weissella, and comprise 36 new emerging species that are presented by means of pathogenicity and disturbance worldwide. We highlight the main characteristics of species to shed light on potential challenges in treatment strategies. Moreover, we investigate the role of various risk factors in the outbreaks, such as environmental conditions, fish density, water quality, and stressors that potentially cause outbreaks of these species. Insights into the temporal and spatial patterns of bacterial outbreaks in rainbow trout aquaculture are provided. Furthermore, the implications of these findings for developing sustainable and targeted disease prevention and control measures are discussed. The presented study serves as a comprehensive update on the state of bacterial outbreaks in rainbow trout aquaculture, emphasizing the importance of continued surveillance and research to sustain the health and productivity of this economically valuable species.

A comprehensive study of Helicobacter pylori infection: molecular analysis, antibacterial susceptibility, and histopathological examination.

Helicobacter pylori is a pathogen associated with gastroduodenal diseases. This study aimed; (i) to investigate H. pylori presence by invasive tests in adult dyspeptic patients, (ii) to determine antibiotic susceptibility and genotypic characteristics of the H. pylori isolates, and (iii) to investigate the relationship between the H. pylori genotypes and the histopathological findings. In this cross-sectional study, gastric biopsy samples from 208 adult dyspeptic patients were used for culture, tissue Polymerase Chain Reaction (PCR), and histopathological analysis. Antibiotic susceptibility of the H. pylori isolates was analyzed by gradient method. Analysis of the virulence genes was performed by monoplex PCR. Genetic profiles (from A to H) were created based on the virulence genes presence. Enterobacterial Repetitive Intergenic Consensus-PCR (ERIC-PCR) was used for the genotyping of the H. pylori isolates. The mean age of the patients was 46 (± 15) years and 128 (61.5%) of them were female. H. pylori positivity was detected by culture, tissue PCR and histopathological examination in 59 (28.4%), 114 (54.8%) and 81 (38.9%) patients, respectively. The overall prevalence of H. pylori was found to be 63% (131/208). All H. pylori isolates were susceptible to tetracycline and amoxicillin. The resistance rates for metronidazole, clarithromycin, levofloxacin, and rifampicin were 67.2%, 27.9%, 34.4% and 13.11%, respectively. Multi drug resistance (MDR) was detected at the rate of 45.9% (28/61). While the most common virulence gene was cagA (93.44%), the least common was vacAm1 (23%). The predominant genetic profile was profile A (47.5%). ERIC-PCR results revealed a total of 26 different patterns. A high prevalence of H. pylori was detected in adult dyspeptic patients as in developing countries. It was observed significant genotypic heterogeneity and virulence gene diversity within the isolates. A considerable resistance rate detected against antibiotics such as clarithromycin, metronidazole, and levofloxacin, which are frequently used in the eradication of H. pylori, should be taken into consideration when creating regional empirical treatment regimens.

The canonical Brucella species-host dependency is changing, however, the antibiotic susceptibility profiles remain unchanged.

Brucellosis is a chronic disease caused by Brucella species with a wide range of hosts, from marine mammals to terrestrial species, but with strict host preferences. With the zoonotic character, the prevalence of human brucellosis cases is a reflection of animal infections. This study aimed to identify 192 Brucella isolates obtained from various sources by Bruce-ladder PCR and to determine their antibiotic susceptibilities by gradient diffusion method (E-test). As a result of the PCR, all human isolates (n = 57) were identified as B. melitensis. While 58 (82.9%) of the cattle isolates were identified as B. abortus, 59 (90.8%) of the sheep isolates were identified as B. melitensis. In addition, 12 (17.1%) of the cattle isolates and 6 (9.2%) of the sheep isolates were determined as B. melitensis and B. abortus, respectively. The primary host change behavior of B. melitensis was 1.9 times higher than that of B. abortus. While gentamicin and ciprofloxacin susceptibilities of Brucella isolates were 100%, tetracycline, doxycycline, streptomycin, trimethoprim/sulfamethoxazole and rifampicin susceptibilities were 99%, 99%, 97.4%, 91.7% and 83.9%, respectively. The lowest sensitivity of the isolates was determined against to cefoperazone as 26%. A triple-drug resistance was detected in 1 B. abortus isolate that included simultaneous resistance to cefoperazone, rifampicin, and trimethoprim/sulfamethoxazole. The high susceptibility profiles we found against to antibiotics such as tetracycline, doxycycline gentamicin and ciprofloxacin, used widely in treatment, are encouraging. However, the change in the canonical Brucella species-primary host preference suggests the need to reconsider eradication program, including updating vaccine formulations.

Investigation of the Genus Flavobacterium as a Reservoir for Fish-Pathogenic Bacterial Species: the Case of Flavobacterium collinsii.

Bacteria of the genus Flavobacterium are recovered from a large variety of environments. Among the described species, Flavobacterium psychrophilum and Flavobacterium columnare cause considerable losses in fish farms. Alongside these well-known fish-pathogenic species, isolates belonging to the same genus recovered from diseased or apparently healthy wild, feral, and farmed fish have been suspected to be pathogenic. Here, we report the identification and genomic characterization of a Flavobacterium collinsii isolate (TRV642) retrieved from rainbow trout spleen. A phylogenetic tree of the genus built by aligning the core genome of 195 Flavobacterium species revealed that F. collinsii stands within a cluster of species associated with diseased fish, the closest one being F. tructae, which was recently confirmed as pathogenic. We evaluated the pathogenicity of F. collinsii TRV642 as well as of Flavobacterium bernardetii F-372T, another recently described species reported as a possible emerging pathogen. Following intramuscular injection challenges in rainbow trout, no clinical signs or mortalities were observed with F. bernardetii. F. collinsii showed very low virulence but was isolated from the internal organs of survivors, indicating that the bacterium is able to survive inside the host and may provoke disease in fish under compromised conditions such as stress and/or wounds. Our results suggest that members of a phylogenetic cluster of fish-associated Flavobacterium species may be opportunistic fish pathogens causing disease under specific circumstances. IMPORTANCE Aquaculture has expanded significantly worldwide in the last decades and accounts for half of human fish consumption. However, infectious fish diseases are a major bottleneck for its sustainable development, and an increasing number of bacterial species from diseased fish raise a great concern. The current study revealed phylogenetic associations with ecological niches among the Flavobacterium species. We also focused on Flavobacterium collinsii, which belongs to a group of putative pathogenic species. The genome contents revealed a versatile metabolic repertoire suggesting the use of diverse nutrient sources, a characteristic of saprophytic or commensal bacteria. In a rainbow trout experimental challenge, the bacterium survived inside the host, likely escaping clearance by the immune system but without provoking massive mortality, suggesting opportunistic pathogenic behavior. This study highlights the importance of experimentally evaluating the pathogenicity of the numerous bacterial species retrieved from diseased fish.

Tentative Epidemiological Cut-Off Values and Distribution of Resistance Genes in Aquatic Pseudomonas Species Isolated from Rainbow Trout.

Epidemiological cut-off value (ECV) analysis for commonly used antimicrobials in aquaculture have not been established for many aquatic pathogens, including Pseudomonas. This study was the first to examine the categorization of 92 aquatic Pseudomonas isolates by calculating seven antimicrobials ECVs using two analytical methods: normalized resistance interpretation and ECOFFinder. Pseudomonas spp. isolates had decreased sensitivity to all antimicrobials examined except for doxycycline and ciprofloxacin. The PCR analysis of the 91 isolates of Pseudomonas spp. detected the tetracycline genes are predominant with the count of 41 genes, including tetA, tetC, tetD, tetM, tetS and tetH, following sulfonamide genes are in 21 isolates including sul1 and sul2, floR gene in 15 isolates and ermA gene in three isolates. Our findings provide an understanding of the antimicrobial categorization of Pseudomonas species, which are significant groups, subgroups, and species for aquaculture due to insufficiently defined breakpoints or cut-off values reported in CLSI and/or EUCAST.

MLST genotypes and quinolone resistance profiles of Campylobacter jejuni isolates from various sources in Turkey.

This study was conducted to determine the overall genetic diversity, as well as prevalence and mechanisms of resistance to quinolone antibiotics of 178 Campylobacter jejuni isolated from humans, cattle, dogs, and chickens in Turkey. Multilocus sequence typing (MLST) and E-test were performed for genotyping and antimicrobial susceptibility testing, respectively. Mismatch Amplification Mutation Assay, Polymerase Chain Reaction (MAMA-PCR) was used to detect point mutations associated with quinolone resistance. Of the 178 isolates tested, 151 were included in 21 clonal complexes (CCs); the remaining 27 isolates did not belong to any existing CCs. CC21, CC353, CC206, and CC257 were the predominant clones, representing 38 % of all C. jejuni isolates tested. The isolates were assigned to 78 different sequence types (STs), three of which were novel (ST 8082, ST 8083, and ST 8084). Resistance to quinolones was found in 73 (41 %) of the isolates (42.85 %, 2.85 %, 20.58 %, and 43.75 % in human, cattle, dog, and chicken isolates, respectively). All of the resistant isolates had Thr-86-Ile mutation in the gyrA gene. The highest Sorensen coefficient index was detected for human/chicken meat and human/dog C. jejuni isolates (Ss = 0.71), suggesting a strong link between the isolates from respective sources. The Simpson diversity index of C. jejuni isolates analyzed was detected between 0.92 and 0.98. The study provides detailed information on the quinolone resistance and MLST-based genetic relatedness of C. jejuni isolates from humans, cattle, dog, and broiler meat in Turkey for the first time, enabling a better understanding of the transmission pathways of C. jejuni in this country. Our results suggest that broiler meat and dogs may be the most important sources of human campylobacteriosis in Turkey.

Genomic insight into Chryseobacterium turcicum sp. nov. and Chryseobacterium muglaense sp. nov. isolated from farmed rainbow trout in Turkey.

Four strains, designated as C-2, C-17T, C-39T and Ch-15, were isolated from farmed rainbow trout samples showing clinical signs during an investigation for a fish-health screening study. The pairwise 16S rRNA gene sequence analysis showed that strain C-17T shared the highest identity level of 98.1 % with the type strain of Chryseobacterium piscium LMG 23089T while strains C-2, C-39T and Ch-15 were closely related to Chryseobacterium balustinum DSM 16775T with an identity level of 99.3 %. A polyphasic approach involving phenotypic, chemotaxonomic and genome-based analyses was employed to determine the taxonomic provenance of the strains. The overall genome relatedness indices including dDDH and ANI analyses confirmed that strains C-2, C-17T, C-39T and Ch-15 formed two novel species within the genus Chryseobacterium. Chemotaxonomic analyses showed that strains C-17T and C-39T have typical characteristics of the genus Chryseobacterium by having phosphatidylethanolamine in their polar lipid profile, MK-6 as only isoprenoid quinone and the presence of iso-C15:0 as major fatty acid. The genome size and G + C content of the strains ranged between 4.4 and 5.0 Mb and 33.5 - 33.6 %, respectively. Comprehensive genome analyses revealed that the strains have antimicrobial resistance genes, prophages and horizontally acquired genes in addition to secondary metabolite-coding gene clusters. In conclusion, based on the polyphasic analyses conducted on the present study, strains C-17T and C-39T are representatives of two novel species within the genus Chryseobacterium, for which the names Chryseobacterium turcicum sp. nov. and Chryseobacterium muglaense sp. nov. with the type strains C-17T (=JCM 34190T = KCTC 82250T) and C-39T (=JCM 34191T = KCTC 822251T), respectively, are proposed.

Genomic insight into Myroides oncorhynchi sp. nov., a new member of the Myroides genus, isolated from the internal organ of rainbow trout (Oncorhynchus mykiss).

The strain M-43T was isolated from the Oncorhynchus mykiss from a fish farm in Mugla, Turkey. Pairwise 16S rRNA gene sequence analysis was used to identify strain M-43T. The strain was a member of the genus Myroides sharing the highest 16S rRNA gene sequence identity levels of 98.7%, 98.3%, and 98.3% with the type strains of M. profundi D25T, M. odoratimimus subsp. odoratimimus CCUG 39352T and M. odoratimimus subsp. xuanwuensis DSM27251T, respectively. A polyphasic taxonomic approach including whole genome-based analyses was employed to confirm the taxonomic provenance of strain M-43T within the genus Myroides. The overall genome relatedness indices (OGRI) for strain M-43T compared with its most closely related type strains M. odoratimimus subsp. xuanwuensis DSM 27251T, M. profundi D25T, and M. odoratimimus subsp. odoratimimus ATCC BAA-634T, were calculated as 25.3%, 25.1%, and 25% for digital DNA-DNA hybridization (dDDH), 83.3%, 83.6%, and 83.4% for average nucleotide identity (ANI) analyses, respectively. The OGRI values between strain M-43T and its close neighbors confirmed that the strain represents a novel species in the genus Myroides. The DNA G + C content of the strain is 33.7%. The major fatty acids are iso-C15:0 and summed feature 9 (iso-C17:1 ω9c and/or 10-methyl C16:0). The predominant polar lipids are phosphatidylethanolamine, an amino-lipid and five unidentified lipids. The major respiratory quinone is MK-6. Chemotaxonomic and phylogenomic analyses of this isolate confirmed that the strain represents a novel species for which the name Myroides oncorhynchi sp. nov. is proposed, with M-43T as the type strain (JCM 34205T = KCTC 82265T).

Shewanella oncorhynchi sp. nov., a novel member of the genus Shewanella, isolated from Rainbow Trout (Oncorhynchus mykiss).

A strain, S-1T was isolated from rainbow trout (Oncorhynchus mykiss) exhibiting clinical symptoms of lens atrophy, inappetence, visual impairment and growth retardation. The strain was identified as representing a member of the genus Shewanella on the basis of the results of 16S rRNA gene sequence analysis. The neighbor-joining phylogenetic tree based on 16S rRNA gene sequences indicated that S-1T clustered with Shewanella putrefaciens JCM 20190T, Shewanella profunda DSM 15900T, and Shewanella hafniensis P010T, sharing 99.3, 98.8 and 87.7% 16S rRNA gene similarities, respectively. A polyphasic taxonomic approach including phenotypic, chemotaxonomic, and genomic characterization was employed to ascertain the taxonomic position of S-1T within the genus Shewanella. The overall genome relatedness indices (OGRI) for S-1T compared with the most closely related type strains S. hafniensis ATCC BAA-1207T, Shewanella baltica NCTC 10735T, S. putrefaciens ATCC 8071T and S. profunda DSM 15900T were calculated as 40.8, 40.1, 28.5 and 27.3% for digital DNA-DNA hybridization (dDDH), and 91.6, 91.0, 86.3 and 85.1% for average nucleotide identity (ANI), respectively. OGRI values between S-1T and its close neighbours confirmed that the strain represents a novel species in the genus Shewanella.The DNA G+C content of the strain is 45.2%. Major fatty acids were C17 : 1ω8c, C15 : 0iso, and summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c). The predominant polar lipids were phosphatidylethanolamine, phospholipid, amino-phospholipid and unidentified lipids. The major respiratory quinones were ubiquinone-8, ubiquinone-7 and menaquinone-7. Chemotaxonomic and phylogenomic analyses of this isolate confirmed that the strain represents a novel species for which the name Shewanella oncorhynchi sp. nov. is proposed, with S-1T as the type strain (JCM 34183T= KCTC 82249T).

Helicobacter turcicus sp. nov., a catalase-negative new member of the Helicobacter genus, isolated from Anatolian Ground Squirrel (Spermophilus xanthoprymnus) in Turkey.

Eleven Gram-negative, curved and S-shaped, oxidase activity positive, catalase activity negative bacterial isolates recovered from faeces of Anatolian ground squirrel (Spermophilus xanthoprymnus) in the city of Kayseri, Turkey, were subjected to a polyphasic taxonomic study. Results of a genus-specific PCR revealed that these isolates belonged to the genus Helicobacter. The 16S rRNA gene sequence analysis revealed that the 11 isolates had over 99 % sequence identity with each other and were most closely related to Helicobacter ganmani CMRI H02T with 97.0-97.1 % identity levels and they formed a novel phylogenetic line within the genus Helicobacter. Faydin-H64 and Faydin-H70T strains were subjected to gyrA and atpA gene and whole genome sequence analyses. These two Helicobacter strains formed separate phylogenetic clades, divergent from other known Helicobacter species. The DNA G+C content and genome size of the strain Faydin-H70T were 35.3 mol% and 1.7 Mb, respectively. Average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain Faydin-H70T and its close phylogenetic neighbour H. winghamensis ATCC BAA-430T were determined as 81.7 and 34.9 %, respectively. Pairwise sequence comparison showed that it was closely related to H. ganmani CMRI H02T however it shared the highest ANI and dDDH values with H. winghamensis ATCC BAA-430T. The data obtained from the polyphasic taxonomy approach, including phenotypic characterization and whole-genome sequences, revealed that these strains represent a novel species within the genus Helicobacter, for which the name Helicobacter turcicus sp. nov., is proposed with Faydin-H70T as the type strain (=DSM 112556T=LMG 32335T).

Description of the two novel species of the genus Helicobacter: Helicobacter anatolicus sp. nov., and Helicobacter kayseriensis sp. nov., isolated from feces of urban wild birds.

A total of 26 Gram-negative, motile, gently curved, and rod-shaped isolates were recovered, during a study to determine the faeco-prevalence of Helicobacter spp. in urban wild birds. Pairwise comparisons of the 16S rRNA gene sequences indicated that these isolates belonged to the genus Helicobacter and phylogenetic analysis based on the 16S rRNA gene sequences showed that the isolates were separated into two divergent groups. The first group consisted of 20 urease-positive isolates sharing the highest 16S rRNA gene sequence identity levels of 98.5-98.6% to H. mustelae ATCC 43772T, while the second group contained six urease-negative isolates with the sequence identity level of 98.5% to the type strain of H. pametensis ATCC 51478T. Five isolates were chosen and subjected to comparative whole-genome analysis. The phylogenetic analysis of the 16S rRNA, gyrA and atpA gene sequences showed that Helicobacter isolates formed two separate phylogenetic clades, differentiating the isolates from the other Helicobacter species. Digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) analyses between strains faydin-H8T, faydin-H23T and their close neighbors H. anseris MIT 04-9362T and H. pametensis ATCC 51478T, respectively, confirmed that both strains represent novel species in the genus Helicobacter. The DNA G+C contents of the strains faydin-H8T and faydin-H23T are 32.0% and 37.6%, respectively. The results obtained for the characterization of the wild bird isolates indicate that they represent two novel species, for which the names Helicobacter anatolicus sp. nov., and Helicobacter kayseriensis sp. nov., are proposed, with faydin-H8T(=LMG 32237T = DSM 112312T) and faydin-H23T(=LMG 32236T = CECT 30508T) as respective type strains.

Campylobacter anatolicus sp. nov., a novel member of the genus Campylobacter isolated from feces of Anatolian Ground Squirrel (Spermophilus xanthoprymnus) in Turkey.

Seventy-four Gram-negative, motile, slightly curved rod-shaped, microaerophilic, oxidase-positive and catalase-negative isolates, recovered from fecal samples of the Anatolian ground squirrel (Spermophilus xanthoprymnus) in Kayseri, Turkey, were subjected to a polyphasic taxonomic study. Results of a genus-specific PCR indicated that all isolates belonged to the genus Campylobacter. 16S rRNA gene sequence analyses revealed the closest match as Campylobacter curvus DSM 6644T with identity levels of 96.41-96.70%. Based on the 16S rRNA gene phylogeny of the 74 isolates, six isolates (faydin-G24, faydin-G52, faydin-G105, faydin-G114, faydin-G129 and faydin-G140T) were chosen as representatives for further characterization. The overall genome relatedness indices for the strain faydin-G140T, compared to the most closely related type strain C. curvus ATCC 35224T, were calculated as 15.2%, 72.5%, and 83.7% for digital DNA-DNA hybridization (dDDH), and average nucleotide identity (ANIb and ANIm), respectively. The G+C content and genome size of the strains ranged between 35.2-35.4 mol% and 1.7-1.8 Mb, respectively. Based on data obtained from the polyphasic taxonomy approach, including phenotypic characterization as well as genomic and chemotaxonomic analyses, these strains are concluded to represent a novel species, for which the name Campylobacter anatolicus sp. nov. is proposed with faydin-G140T as the type strain (=DSM 112311T = LMG 32238T).

Flavobacterium erciyesense sp. nov., a putative non-pathogenic fish symbiont.

During a study aiming at isolation and genomic characterization of non-pathogenic fish symbionts, strain F-328T was isolated from skin mucus of healthy-seeming rainbow trout (Oncorhynchus mykiss) and subjected to polyphasic characterization, including a comprehensive genome analysis. Strain F-328T was Gram stain negative, none-gliding, strictly aerobic, and rod shaped. The 16S rRNA gene sequence of strain F-328T exhibited the highest level of identity (98.9%) with F. turcicum F-339T. The major fatty acids were iso-C15:0, C15:1 ω6c, and summed feature 3 (C16:1 ω7c, C16:1 ω6c). The polar lipid profile consisted mainly of phosphatidylethanolamine and aminolipids, while the predominant menaquinone was MK-6. The DNA G + C content and genome size of the strain were 35.3% and 3.4 Mb, respectively. Strain F-328T shows 93.8% average nucleotide identity and 53% digital DNA-DNA hybridization identity with the closest type strain F. turcicum F-339T. In addition, strain F-328T was found to carry antimicrobial resistance genes, which confer resistance to several antimicrobials, including aminoglycoside, macrolides, and streptogramin. Differential phenotypic properties, together with the phylogenetic inference, demonstrate that strain F-328T should be classified as a novel species of the genus Flavobacterium for which the name Flavobacterium erciyesense sp. nov. is proposed, with F-328T as the type strain (= JCM 34201T = KCTC 82261T).