Coinheritance of chromosomes 3 and 11 in the patients with autosomal recessive polycythemia from Chuvachia

Inheritance of chromosomes 3 and 11 in the families with Chuvash autosomal recessive polycythemia and in control group with no disease symptoms was examined using polymorphic dinucleotide markers D3S1597 and D3S1263, mapped to region 3p25, and D11S4111, D11S4127, and D11S1356, mapped to region 11q23. All patients were homozygous for the C598T mutation in the VHL gene (3p25). The analysis showed that in 75% of the cases, chromosome 3 carrying C598T mutation was coinherited with certain chromosome 11, which differed from 50%, expected upon independent inheritance of each chromosome. In case of chromosome 3 without C598T mutation, this pattern was observed neither in healthy sibs form the families with autosomal recessive polycythemia (44%), nor in the control group (43%). These results suggest that in case of the C598T mutation in the VHL gene, chromosomal loci 3p25 and 11q23 are inherited not independently, compared to the inheritance of these loci in the absence of the mutation in healthy sibs from the affected families (chi2 = 16.14; P < 0.001), and also in the control family sample (chi2 = 17.91; P < 0.001).     

<Emphasis Type="Italic">Streptomyces lutosisoli</Emphasis> sp. nov., a novel actinomycete isolated from muddy soil

A novel Gram-stain positive, spore-forming, aerobic actinomycete, designated strain NEAU-QTH3-11^T, was isolated from muddy soil collected from a stream in Qitaihe, Heilongjiang Province, northeast China and characterised using a polyphasic approach. The 16S rRNA gene sequence analysis showed that strain NEAU-QTH3-11^T belongs to the genus Streptomyces and is closely related to Streptomyces rhizosphaerihabitans NBRC 109807^T (99.38%) and Streptomyces mirabilis JCM 4791^T (99.03%). Phylogenetic analysis based on the 16S rRNA gene sequences indicated that the strain formed a cluster with S. rhizosphaerihabitans NBRC 109807^T and Streptomyces siamensis NBRC 108799^T (98.62%). The menaquinones were identified as MK-9(H₈), MK-9(H₆) and MK-9(H₄). The phospholipid profile was found to consist of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, an unidentified phospholipid and an unidentified lipid. The major fatty acids were identified as anteiso-C_15:0, iso-C_16:0, C_16:0 and C_15:0. However, multilocus sequence analysis based on five house-keeping genes (atpD, gyrB, rpoB, recA and trpB), low DNA-DNA hybridization results and some phenotypic, physiological and biochemical properties could differentiate the strain from its close relatives in the genus Streptomyces. Therefore, strain NEAU-QTH3-11^T is considered to represent a novel species of the genus Streptomyces, for which the name Streptomyces lutosisoli sp. nov. is proposed, with NEAU-QTH3-11^T (=DSM 42165^T=CGMCC 4.7198^T) as the type strain.     

<Emphasis Type="SmallCaps">d</Emphasis>-Xylose fermentation,xylitol production and xylanase activities by seven new species of <Emphasis Type="Italic">Sugiyamaella</Emphasis>

Sixteen yeast isolates identified as belonging to the genus Sugiyamaella were studied in relation to D-xylose fermentation, xylitol production, and xylanase activities. The yeasts were recovered from rotting wood and sugarcane bagasse samples in different Brazilian regions. Sequence analyses of the internal transcribed spacer (ITS) region and the D1/D2 domains of large subunit rRNA gene showed that these isolates belong to seven new species. The species are described here as Sugiyamaella ayubii f.a., sp. nov. (UFMG-CM-Y607^T = CBS 14108^T), Sugiyamaella bahiana f.a., sp. nov. (UFMG-CM-Y304^T = CBS 13474^T), Sugiyamaella bonitensis f.a., sp. nov. (UFMG-CM-Y608^T = CBS 14270^T), Sugiyamaella carassensis f.a., sp. nov. (UFMG-CM-Y606^T = CBS 14107^T), Sugiyamaella ligni f.a., sp. nov. (UFMG-CM-Y295^T = CBS 13482^T), Sugiyamaella valenteae f.a., sp. nov. (UFMG-CM-Y609^T = CBS 14109^T) and Sugiyamaella xylolytica f.a., sp. nov. (UFMG-CM-Y348^T = CBS 13493^T). Strains of the described species S. boreocaroliniensis, S. lignohabitans, S. novakii and S. xylanicola, isolated from rotting wood of Brazilian ecosystems, were also compared for traits relevant to xylose metabolism. S. valenteae sp. nov., S. xylolytica sp. nov., S. bahiana sp. nov., S. bonitensis sp. nov., S. boreocarolinensis, S. lignohabitans and S. xylanicola were able to ferment d-xylose to ethanol. Xylitol production was observed for all Sugiyamaella species studied, except for S. ayubii sp. nov. All species studied showed xylanolytic activity, with S. xylanicola, S. lignohabitans and S. valenteae sp. nov. having the highest values. Our results suggest these Sugiyamaella species have good potential for biotechnological applications.     

<Emphasis Type="Italic">Spirosoma pomorum</Emphasis> sp. nov., isolated from apple orchard soil

A Gram-negative, motile, rod-shaped, aerobic bacterial strain, designated S7-2-11^T, was isolated from apple orchard soil from Gyeongsangnam-do Province, Republic of Korea, and was characterized taxonomically using a polyphasic approach. 16S rRNA gene sequence analysis indicated that strain S7-2-11^T belongs to the family Cytophagaceae in phylum Bacteroidetes, and is closely related to Spirosoma luteolum 16F6E^T (94.2% identity), Spirosoma knui 15J8-12^T (92.7%), and Spirosoma linguale DSM 74^T (91.0%). The G + C content of the genomic DNA of strain S7-2-11^T was 49.8 mol%. Strain S7-2-11^T contained summed feature 3 (C_16:1 ω7c/C_16:1 ω6c; 35.1%), C_16:1 ω5c (22.4%), C_15:0 iso (13.9%), and C_17:0 iso 3-OH (10.6%) as major cellular fatty acids, and MK-7 as the predominant respiratory quinone. The main polar lipids were phosphatidylethanolamine, an unidentified aminophospholipid, and two unidentified polar lipids. Phenotypic and chemotaxonomic data supported the affiliation of strain S7-2-11^T with the genus Spirosoma. The results of physiological and biochemical tests showed the genotypic and phenotypic differentiation of the isolate from recognized Spirosoma species. On the basis of its phenotypic properties, genotypic distinctiveness, and chemotaxonomic features, strain S7-2-11^T represents a novel species of the genus Spirosoma, for which the name Spirosoma pomorum sp. nov. is proposed. The type strain is S7-2-11^T (= KCTC 52726^T = JCM 32130^T).     

A novel dominant rice male sterility mutant, <Emphasis Type="Italic">OsDMS-1</Emphasis>, simultaneously controlled by independent loci on chromosomes 1, 2, and 3

We found a rice dominant genetic male-sterile mutant OsDMS-1 from tissue culture-regenerated offspring of Zhonghua 11 (japonica rice). Compared to Zhonghua 11, OsDMS-1 mutant anthers were narrow and pale and incapable of pollen release although the glume opened normally. Approximately 81.4% of this mutant pollen was small and malformed and could not be stained by iodine treatment. A paraffin section assay showed delayed degradation of the OsDMS-1 mutant tapetum without starch accumulation in the mutant pollen, ultimately leading to pollen abortion. Classical genetic analysis indicated that only one dominant gene controlled the sterility in the OsDMS-1 mutant. However, molecular mapping suggested three loci simultaneously control male sterility in this mutant: OsDMS-1A (on chromosome 1), flanked by InDel markers C1D4 and C1D5, OsDMS-1B (on chromosome 2), flanked by InDel markers C2D3 and C2D10, and OsDMS-1C (on chromosome 3), flanked by InDel markers 0315 and C3D3. Molecular mapping disagreed with classical genetic analysis regarding the number of genes controlling the OsDMS-1 mutant, indicating a novel mechanism underlying sterility in OsDMS-1. We present two hypotheses to explain this novel inheritance behavior: one is described as Parent-Originated Loci Tying Inheritance (POLTI); while the alternate hypothesis is described as Loci Recombination Lethal (LRL).     

Phenotypes and <Emphasis Type="Italic">PRRT2</Emphasis> mutations in Chinese families with benign familial infantile epilepsy and infantile convulsions with paroxysmal choreoathetosis

Background

Mutations in the PRRT2 gene have been identified as the major cause of benign familial infantile epilepsy (BFIE), paroxysmal kinesigenic dyskinesia (PKD) and infantile convulsions with paroxysmal choreoathetosis/dyskinesias (ICCA). Here, we analyzed the phenotypes and PRRT2 mutations in Chinese families with BFIE and ICCA.

Methods

Clinical data were collected from 22 families with BFIE and eight families with ICCA. PRRT2 mutations were screened using PCR and direct sequencing.

Results

Ninety-five family members were clinically affected in the 22 BFIE families. During follow-up, two probands had one seizure induced by diarrhea at the age of two years. Thirty-one family members were affected in the eight ICCA families, including 11 individuals with benign infantile epilepsy, nine with PKD, and 11 with benign infantile epilepsy followed by PKD. Two individuals in one ICCA family had PKD or ICCA co-existing with migraine. One affected member in another ICCA family had experienced a fever-induced seizure at 7 years old. PRRT2 mutations were detected in 13 of the 22 BFIE families. The mutation c.649_650insC (p.R217PfsX8) was found in nine families. The mutations c.649delC (p.R217EfsX12) and c.904_905insG (p.D302GfsX39) were identified in three families and one family, respectively. PRRT2 mutations were identified in all eight ICCA families, including c.649_650insC (p.R217PfsX8), c.649delC (p.R217EfsX12), c.514_517delTCTG (p.S172RfsX3) and c.1023A?>?T (X341C). c.1023A?>?T is a novel mutation predicted to elongate the C-terminus of the protein by 28 residues.

Conclusions

Our data demonstrated that PRRT2 is the major causative gene of BFIE and ICCA in Chinese families. Site c.649 is a mutation hotspot: c.649_650insC is the most common mutation, and c.649delC is the second most common mutation in Chinese families with BFIE and ICCA. As far as we know, c.1023A?>?T is the first reported mutation in exon 4 of PRRT2. c.649delC was previously reported in PKD, ICCA and hemiplegic migraine families, but we further detected it in BFIE-only families. c.904_905insG was reported in an ICCA family, but we identified it in a BFIE family. c.514_517delTCTG was previously reported in a PKD family, but we identified it in an ICCA family. Migraine and febrile seizures plus could co-exist in ICCA families.

     

Integrated gene mapping and synteny studies give insights into the evolution of a sex proto-chromosome in <Emphasis Type="Italic">Solea senegalensis</Emphasis>

The evolution of genes related to sex and reproduction in fish shows high plasticity and, to date, the sex determination system has only been identified in a few species. Solea senegalensis has 42 chromosomes and an XX/XY chromosome system for sex determination, while related species show the ZZ/ZW system. Next-generation sequencing (NGS), multi-color fluorescence in situ hybridization (mFISH) techniques, and bioinformatics analysis have been carried out, with the objective of revealing new information about sex determination and reproduction in S. senegalensis. To that end, several bacterial artificial chromosome (BAC) clones that contain candidate genes involved in such processes (dmrt1, dmrt2, dmrt3, dmrt4, sox3, sox6, sox8, sox9, lh, cyp19a1a, amh, vasa, aqp3, and nanos3) were analyzed and compared with the same region in other related species. Synteny studies showed that the co-localization of dmrt1-dmrt2-drmt3 in the largest metacentric chromosome of S. senegalensis is coincident with that found in the Z chromosome of Cynoglossus semilaevis, which would potentially make this a sex proto-chromosome. Phylogenetic studies show the close proximity of S. senegalensis to Oryzias latipes, a species with an XX/XY system and a sex master gene. Comparative mapping provides evidence of the preferential association of these candidate genes in particular chromosome pairs. By using the NGS and mFISH techniques, it has been possible to obtain an integrated genetic map, which shows that 15 out of 21 chromosome pairs of S. senegalensis have at least one BAC clone. This result is important for distinguishing those chromosome pairs of S. senegalensis that are similar in shape and size. The mFISH analysis shows the following co-localizations in the same chromosomes: dmrt1-dmrt2-dmrt3, dmrt4-sox9-thrb, aqp3-sox8, cyp19a1a-fshb, igsf9b-sox3, and lysg-sox6.     

Taxonomic description and draft genome of <Emphasis Type="Italic">Pseudomonas sediminis</Emphasis> sp. nov., isolated from the rhizospheric sediment of <Emphasis Type="Italic">Phragmites karka</Emphasis>

The taxonomic position of a Gram-stain-negative, rod-shaped bacterial strain, designated PI11^T, isolated from the rhizospheric sediment of Phragmites karka was characterized using a polyphasic approach. Strain PI11^T could grow optimally at 1.0% NaCl concentration with pH 7.0 at 30°C and was positive for oxidase and catalase but negative for hydrolysis of starch, casein, and esculin ferric citrate. Phylogenetic analysis of 16S rRNA gene sequences indicated that the strain PI11^T belonged to the genus Pseudomonas sharing the highest sequence similarities with Pseudomonas indoloxydans JCM 14246^T (99.72%), followed by, Pseudomonas oleovorans subsp. oleovorans DSM 1045^T (99.29%), Pseudomonas toyotomiensis JCM 15604^T (99.15%), Pseudomonas chengduensis DSM 26382^T (99.08%), Pseudomonas oleovorans subsp. lubricantis DSM 21016^T (99.08%), and Pseudomonas alcaliphila JCM 10630^T (99.01%). Experimental DNA-DNA relatedness between strain PI11^T and P. indoloxydans JCM 14246^T was 49.4%. The draft genome of strain PI11^T consisted of 4,884,839 bp. Average nucleotide identity between the genome of strain PI11^T and other closely related type strains ranged between 77.25–90.74%. The polar lipid pattern comprised of phosphatidylglycerol, diphosphatidylglycerol, and phosphatidylcholine. The major (> 10%) cellular fatty acids were C_18:1ω6c/ω7c, C_16:1ω6c/ω7c, and C_16:0. The DNA G + C content of strain PI11^T was 62.4 mol%. Based on the results of polyphasic analysis, strain PI11^T was delineated from other closely related type strains. It is proposed that strain PI11^T represents represents a novel species of the genus Pseudomonas, for which the name Pseudomonas sediminis sp. nov. is proposed. The type strain is PI11^T (= KCTC 42576^T = DSMZ 100245^T).     

<Emphasis Type="Italic">Streptomyces gamaensis</Emphasis> sp. nov., a novel actinomycete with antifungal activity isolated from soil in Gama,Chad

During an investigation exploring potential sources of novel species and natural products, a novel actinomycete with antifungal activity, designated strain NEAU-Gz11^T, was isolated from a soil sample, which was collected from Gama, Chad. The isolate was found to have morphological and chemotaxonomic characteristics typical of members of the genus Streptomyces. 16S rRNA gene sequence similarity studies showed that strain NEAU-Gz11^T belongs to the genus Streptomyces with high sequence similarity to Streptomyces hiroshimensis JCM 4098^T (98.0 %). Similarities to other type strains of the genus Streptomyces were lower than 98.0 %. However, the physiological and biochemical characteristics and low levels of DNA–DNA relatedness could differentiate the isolate genotypically and phenotypically from S. hiroshimensis JCM 4098^T. Therefore, the strain is concluded to represent a novel species of the genus Streptomyces, for which the name Streptomyces gamaensis sp. nov. is proposed. The type strain is NEAU-Gz11^T (=CGMCC 4.7304^T=DSM 101531^T).     

Characterisation and mapping of adult plant stripe rust resistance in wheat accession Aus27284

Key message

A new adult plant stripe rust resistance gene, Yr80, was identified in a common wheat landrace Aus27284. Linked markers were developed and validated for their utility in marker-assisted selection.

Abstract

Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is among the most important constraints to global wheat production. The identification and characterisation of new sources of host plant resistance enrich the gene pool and underpin deployment of resistance gene pyramids in new cultivars. Aus27284 exhibited resistance at the adult plant stage against predominant Pst pathotypes and was crossed with a susceptible genotype Avocet S. A recombinant inbred line (RIL) population comprising 121 lines was developed and tested in the field at three locations in 2016 and two in 2017 crop seasons. Monogenic segregation for adult plant stripe rust response was observed among the Aus27284/Avocet S RIL population and the underlying locus was temporarily designated YrAW11. Bulked-segregant analysis using the Infinium iSelect 90K SNP wheat array placed YrAW11 in chromosome 3B. Kompetitive allele specific PCR (KASP) primers were designed for the linked SNPs and YrAW11 was flanked by KASP_65624 and KASP_53292 (3 cM) proximally and KASP_53113 (4.9 cM) distally. A partial linkage map of the genomic region carrying YrAW11 comprised nine KASP and two SSR markers. The physical position of KASP markers in the pseudomolecule of chromosome 3B placed YrAW11 in the long arm and the location of markers gwm108 and gwm376 in the deletion bin 3BL2-0.22 supported this conclusion. As no other stripe rust resistance locus has been reported in chromosome 3BL, YrAW11 was formally designated Yr80. Marker KASP_ 53113 was polymorphic among 94% of 81 Australian wheat cultivars used for validation.

     

Deleterious mutations in various <Emphasis Type="Italic">Drosophila melanogaster</Emphasis> strains carrying meiotic mutation <Emphasis Type="Italic">c(3)G</Emphasis>

In the absence of meiotic recombination, deleterious mutations, decreasing the viability, are accumulated and fixed in small Drosophila populations. Study of the viability of hybrid progenies of three laboratory Drosophila melanogaster strains carrying meiotic mutation c(3)G ¹⁷ has suggested that the deleterious mutations are negatively synergistic in their interaction. The deleterious mutations localized to the pericentromeric region of chromosome 3 are threefold more efficient as compared with the mutations located in distal regions. Substitution of a new chromosome for the balancer chromosome in a strain with meiotic mutation c(3)G ¹⁷ partially restores (by ～20%) the viability of homozygotes c(3)G ¹⁷ /c(3)G ¹⁷ over the first 20–30 generations. Further cultivation for 30 generations with the same balancer again decreases the viability to the initial level. An epigenetic nature of deleterious mutations is discussed.     

Revealing physiological and genetic properties of a dominant maize dwarf <Emphasis Type="Italic">Dwarf11</Emphasis> (<Emphasis Type="Italic">D11</Emphasis>) by integrative analysis

Plant height is an important agronomic trait involved in lodging resistance and harvest index. The identification and characterization of mutants that are defective in plant height have implications for trait improvement in breeding programs. Two dominant maize dwarf mutants D8 and D9 have been well-characterized. Here, we report the characterization of a dominant maize dwarf mutant Dwarf11 (D11). Dwarf stature of D11 was mainly attributed to the inhibition of longitudinal cell elongation. The levels of bioactive GA₃ were significantly lower in D11. Contrarily, D8 mutant accumulates markedly higher levels of GA₃. The expression of GA biosynthetic and catabolic genes was dramatically decreased in D11. Expression variations of d8 and d9 genes were not observed in D11 mutant. Moreover, genetic suppressors of D11 were identified in inbred line Chang 7-2. Integrated omics data indicated that D11 is a novel dominant maize dwarf. The ultimate D11 gene cloning and its regulatory network elucidation may strengthen our understanding of the genetic basis of plant architecture and provide cues for breeding of crops with plant height ideotypes.     

<Emphasis Type="Italic">Spirosoma flavus</Emphasis> sp. nov., a novel bacterium from soil of Jeju Island

A novel, Gram-staining negative, yellow pigmented bacterial strain, designated 15J11-2^T, was isolated from soil sample on Jeju Island, Republic of Korea. The strain was subjected to a taxonomic study using a polyphasic approach. The strain was able to grow at temperature range from 10°C to 30°C, pH 7–8, and in presence of 0–1% (w/v) NaCl. Comparative 16S rRNA gene sequence analysis showed that strain 15J11-2^T belongs to the genus Spirosoma and levels of 16S rRNA gene sequence similarity ranged from 91.5% to 89.8%. The genomic DNA G + C content of strain 15J11-2^T was 46.0 mol%. The isolate contained phosphatidylethanolamine and an unidentified aminophospholipid as the main polar lipids, menaquinone MK-7 as the predominant respiratory quinone, and summed feature 3 (C_16:1ω6c/C_16:1ω7c; 39.4%), C_16:1ω5c (27.1%), and C_16:0 (13.0%) as the major fatty acids, which supported the affiliation of strain 15J11-2^T to the genus Spirosoma. The results of physiological and biochemical tests allowed genotypic and phenotypic differentiation of strain 15J11-2^T from recognized Spirosoma species. On the basis of its phenotypic properties, genotypic distinctiveness, chemotaxonomic features, strain 15J11-2^T represents a novel species of the genus Spirosoma, for which the name Spirosoma flavus sp. nov. is proposed. The type strain is 15J11-2^T (= KCTC 52026^T = JCM 31998^T).     

<Emphasis Type="Italic">Spirosoma lituiforme</Emphasis> sp. nov., isolated from soil

A Gram-staining-negative, non-motile, curved rod-shaped, aerobic bacterium, designated S1-2-4^T, was isolated from soil in Jeollabuk-do province, Republic of Korea, and was characterized taxonomically using a polyphasic approach. Comparative 16S rRNA gene sequence analysis showed that strain S1-2-4^T was a member of the family Cytophagaceae and most closely related to ‘Spirosoma radiotolerans’ DG5A (97.2%), Spirosoma fluviale MSd3^T (96.4%), and Spirosoma linguale DSM 74^T (96.3%). The genomic DNA G + C content of strain S1-2-4^T was 49.7 mol%. The major fatty acids were summed feature 3 (C_16:1ω7c/C_16:1ω6c), C_16:1ω5c, and C_16:0, and the major polar lipid was phosphatidylethanolamine. MK-7 was the predominant respiratory quinone. Phenotypic and chemotaxonomic data supported the affiliation of strain S1-2-4^T with the genus Spirosoma. DNA-DNA hybridization between strain S1-2-4^T and ‘Spirosoma radiotolerans’ showed relatively low DNA-DNA relatedness (31%). Strain S1-2-4^T could be distinguished from its closest phylogenetic neighbors based on its phenotypic, genotypic, and chemotaxonomic features. Therefore, strain S1-2-4^T represents a novel member of the genus Spirosoma, for which the name Spirosoma lituiforme sp. nov. is proposed. The type strain is S1-2-4^T (= KCTC 52724^T = JCM 32128^T).     

Chromosome nondisjunction in <Emphasis Type="Italic">Drosophila</Emphasis> strains mutant for tumor suppressor Merlin

The effect of mutation for gene Merlin on chromosome disjunction in Drosophila during meiosis was genetically studied. Chromosome nondisjunction was not registered in females heterozygous for this mutation and containing structurally normal X chromosomes. In cases when these females additionally contained inversion in one of chromosomes X, a tendency toward the appearance of nondisjunction events was observed in individuals containing mutation in the heterozygote. The genetic construct was obtained allowing the overexpression of protein corresponding to a sterile allele Mer ³ in the germ cell line. This construct relieves the lethal effect of Mer ⁴ mutation. The ectopic expression of this mutant protein leads to chromosome nondisjunction in male meiosis.     

<Emphasis Type="Italic">Azohydromonas riparia</Emphasis> sp. nov. and <Emphasis Type="Italic">Azohydromonas ureilytica</Emphasis> sp. nov. isolated from a riverside soil in South Korea

White and pale yellow coloured bacteria were isolated from the riverside soil, Daejeon, South Korea, and were designated UCM-11^T, UCM-F25, and UCM-80^T. We found that all strains were able to reduce nitrate, and the cells were aerobic and motile. The DNA G+C contents of UCM-11^T, UCM-F25, and UCM-80^T were between 68.9 to 71.2 mol% and the main ubiquinone was observed as Q-8. Based on16S rRNA gene sequences, strains UCM-11^T and UCM-F25 were found to closely match with Azohydromonas australica IAM 12664^T (98.48–98.55%), and the strain UCM-80^T was the closest match with Azohydromonas lata IAM 12599^T (98.34%). The presence of summed feature 3 (C_16:1 ω7c and/or C_16:1 ω6c), C_16:0, summed feature 8 (C_18:1 ω7c and/or C_18:1 ω6c) as well as twokinds of hydroxyfatty acids consisting of C_10:0 3-OH and C_12:0 2-OH, and branched fatty acids containing C_16:0 iso and C_17:0 cyclo were detected in all the strains. Phosphatidylethanolamine was a major polar lipid. DNA–DNA relatedness confirmed UCM-11^T, UCM-F25 and UCM-80^T as novel members of the genus Azohydromonas. Based on the morphological, physiological, biochemical and genotypic characteristics, we suggest that strains UCM-11^T, UCM-F25, and UCM-80^T represent novel species within the genus Azohydromonas. The names Azohydromonas riparia sp. nov., and Azohydromonas ureilytica sp. nov. are proposed for the type strains UCM-11^T (=KACC 18570^T =NBRC 111646^T) and UCM-80^T (=KACC 18576^T =NBRC 111658^T), respectively.