Recognition of a New Cr(VI)-Reducing Strain and Study of the Potential Capacity for Reduction of Cr(VI) of the Strain.

The biotransformation of hexavalent chromium [Cr(VI)] via Cr(VI)-reducing microorganisms is considered an ecofriendly approach to detoxify Cr(VI). A new Cr(VI)-reducing bacterium named Microbacterium sp. QH-2 was isolated in this study. Scanning electron microscopy (SEM) images showed protrusions on the bacterial surface of strain QH-2 after an 18 h incubation in media under 10 mM Cr(VI) treatment. Results of the experiments on the capacity of reducing Cr(VI) indicated that strain QH-2 could reduce 100% Cr(VI) less than 48-96 h. When media with 4 mM Cr(VI) were incubated, the fastest reduction rate of strain QH-2 could come up to 2.17 mg/L Cr(VI) h-1. Furthermore, strain QH-2 could reduce Cr(VI) over the pH between 7 and 10. The optimum pH to reduce Cr(VI) by strain QH-2 was 9. Strain QH-2 also exhibited a relatively high tolerance even to 20 mM Cr(VI). These results declared that strain QH-2 had the potential to detoxify Cr(VI) in the Cr(VI)-contaminated soil or effluent.

Saccharothrix tharensis sp. nov., an actinobacterium isolated from the Thar Desert, India.

The taxonomic provenance of a filamentous actinobacterial strain isolated from a desert soil was established using a polyphasic approach. The strain has chemotaxonomic and morphological properties consistent with its classification in the genus Saccharothrix. It forms a distinct branch in the Saccharothrix 16S rRNA gene tree, related to the type strain of Saccharothrix saharensis (96.7%) but was distinguished readily from it using a combination of phenotypic properties. The genotypic and phenotypic data show that the strain represents a novel species in the genus Saccharothrix, for which the name Saccharothrix tharensis sp. nov. is proposed with the type strain TD-093T (= KCTC 39724T = MCC 2832T).

Imaging with Mass Spectrometry of Bacteria on the Exoskeleton of Fungus-Growing Ants.

Mass spectrometry imaging is a powerful analytical technique for detecting and determining spatial distributions of molecules within a sample. Typically, mass spectrometry imaging is limited to the analysis of thin tissue sections taken from the middle of a sample. In this work, we present a mass spectrometry imaging method for the detection of compounds produced by bacteria on the outside surface of ant exoskeletons in response to pathogen exposure. Fungus-growing ants have a specialized mutualism with Pseudonocardia, a bacterium that lives on the ants' exoskeletons and helps protect their fungal garden food source from harmful pathogens. The developed method allows for visualization of bacterial-derived compounds on the ant exoskeleton. This method demonstrates the capability to detect compounds that are specifically localized to the bacterial patch on ant exoskeletons, shows good reproducibility across individual ants, and achieves accurate mass measurements within 5 ppm error when using a high-resolution, accurate-mass mass spectrometer.

Agromyces marinus sp. nov., a novel actinobacterium isolated from sea sediment.

Two novel Gram-stain-positive actinobacteria, designated H23-8(T) and H23-19, were isolated from a sea sediment sample and their taxonomic positions were investigated by a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequence comparisons showed that these isolates were closely related to the members of the genus Agromyces, with similarity range of 94.5-97.4%. Strains H23-8(T) and H23-19 contained L-2,4-diaminobutyric acid, D-alanine, D-glutamic acid and glycine in their peptidoglycan. The predominant menaquinones were MK-13 and MK-12, and the major fatty acids were anteiso-C(15:0), anteiso-C(17:0) and iso-C(16:0). The DNA G+C content was 72.3-72.5 mol%. The chemotaxonomic characteristics of the isolates matched those described for members of the genus Agromyces. The results of phylogenetic analysis and DNA-DNA hybridization, along with differences in phenotypic characteristics between strains H23-8(T) and H23-19 and the species of the genus Agromyces with validly published names, indicated that the two isolates should be assigned to a novel species of the genus Agromyces, for which the name Agromyces marinus sp. nov. is proposed; the type strain is H23-8(T) (=NBRC 109019(T)=DSM 26151(T)).

Laminaria japonica Extract, an Inhibitor of Clavibater michiganense Subsp. Sepedonicum.

Bacterial ring rot of potato is one of the most serious potato plant and tuber diseases. Laminaria japonica extract was investigated for its antimicrobial activity against Clavibater michiganense subsp. sepedonicum (Spieckermann & Kotthoff) Davis et al., the causative agent of bacterial ring rot of potato. The results showed that the optimum extraction conditions of antimicrobial substances from L. japonica were an extraction temperature of 80°C, an extraction time of 12 h, and a solid to liquid ratio of 1∶25. Active compounds of L. japonica were isolated by solvent partition, thin layer chromatography (TLC) and column chromatography. All nineteen fractionations had antimicrobial activities against C. michiganense subsp. sepedonicum, while Fractionation three (Fr.3) had the highest (P<0.05) antimicrobial activity. Chemical composition analysis identified a total of 26 components in Fr.3. The main constituents of Fr.3 were alkanes (80.97%), esters (5.24%), acids (4.87%) and alcohols (2.21%). Antimicrobial activity of Fr.3 against C. michiganense subsp. sepedonicum could be attributed to its ability to damage the cell wall and cell membrane, induce the production of reactive oxygen species (ROS), increase cytosolic Ca2+ concentration, inhibit the glycolytic pathway (EMP) and tricarboxylic acid (TCA) cycle, inhibit protein and nucleic acid synthesis, and disrupt the normal cycle of DNA replication. These findings indicate that L. japonica extracts have potential for inhibiting C. michiganense subsp. sepedonicum.

Geodermatophilus tzadiensis sp. nov., a UV radiation-resistant bacterium isolated from sand of the Saharan desert.

Three novel Gram-positive, aerobic, actinobacterial strains, CF5/2(T), CF5/1 and CF7/1, were isolated in 2007 during environmental screening of arid desert soil in the Sahara desert, Chad. Results from riboprinting, MALDI-TOF protein spectra and 16S rRNA sequence analysis confirmed that all three strains belonged to the same species. Phylogenetic analysis of 16S rRNA sequences with the strains' closest relatives indicated that they represented a distinct species. The three novel strains also shared a number of physiological and biochemical characteristics distinct from previously named Geodermatophilus species. The novel strains' peptidoglycan contained meso-diaminopimelic acid; their main phospholipids were phosphatidylcholine, phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylinositol and a small amount of phosphatidylglycerol; MK-9(H4) was the dominant menaquinone. The major cellular fatty acids were the branched-chain saturated acids iso-C16:0 and iso-C15:0. Galactose was detected as diagnostic sugar. Based on these chemotaxonomic results, 16S rRNA gene sequence analysis and DNA-DNA hybridization between strain CF5/2(T) and the type strains of Geodermatophilus saharensis, Geodermatophilus arenarius, Geodermatophilus nigrescens, Geodermatophilus telluris and Geodermatophilus siccatus, the isolates CF5/2(T), CF5/1 and CF7/1 are proposed to represent a novel species, Geodermatophilus tzadiensis, with type strain CF5/2(T)=DSM 45416=MTCC 11411 and two reference strains, CF5/1 (DSM 45415) and CF7/1 (DSM 45420).

Geodermatophilus saharensis sp. nov., isolated from sand of the Saharan desert in Chad.

A novel Gram-positive, aerobic, actinobacterial strain, CF5/5, was isolated from soil in the Sahara desert, Chad. It grew best at 20-35 °C and at pH 6.0-8.0 and with 0-4 % (w/v) NaCl, forming black-colored colonies. Chemotaxonomic and molecular characteristics of the isolate matched those described for members of the genus Geodermatophilus. The DNA G + C content was 75.9 mol%. The peptidoglycan contained meso-diaminopimelic acid; galactose and xylose were detected as diagnostic sugars. The main phospholipids were diphosphatidylglycerol, phosphatidylcholine, and phosphatidylinositol; MK-9(H(4)) was the dominant menaquinone. The major cellular fatty acids were: iso-C(16:0) and iso-C(15:0). The 16S rRNA gene showed 95.6-98.3 % sequence similarity with the other named members of the genus Geodermatophilus. Based on the polyphasic taxonomy data, the isolate is proposed to represent a novel species, Geodermatophilus saharensis with the type strain CF5/5(T) = DSM 45423 = CCUG 62813 = MTCC 11416.

Jatrophihabitans endophyticus gen. nov., sp. nov., an endophytic actinobacterium isolated from a surface-sterilized stem of Jatropha curcas L.

A short rod-shaped Gram-stain-positive actinobacterium was isolated as an endophyte from the tissues of Jatropha curcas cv. KB27 and was investigated by means of a polyphasic taxonomic approach. An analysis of its 16S rRNA gene sequence indicated that strain S9-650(T) forms an individual line of descent and is related to certain members of the suborder Frankineae, order Actinomycetales (<95 % sequence similarity). Distance-matrix and neighbour-joining analyses set the branching point of the novel isolate between two clades, one being represented by members of the genera Frankia (family Frankiaceae) and Acidothermus (family Acidothermaceae) and the other by members of the genera Geodermatophilus, Blastococcus and Modestobacter (family Geodermatophilaceae). The organism had meso-diaminopimelic acid as the diagnostic diamino acid in the cell-wall peptidoglycan. The acyl type was found to be N-glycolylated. The major menaquinone was MK-9(H4) and the fatty acid profile was characterized by the predominance of iso-C16 : 0, C18 : 1ω9c, anteiso-C17 : 0 and C17 : 1ω8c. The polar lipids comprised diphosphatidylglycerol, an unidentified glycolipid, phospholipids and aminolipids. The G+C content of the genomic DNA was 71.2 mol%. The distinct phylogenetic position and the phenotypic markers that clearly separate the novel organism from all other members of the suborder Frankineae indicate that strain S9-650(T) represents a novel species in a new genus, for which the name Jatrophihabitans endophyticus gen. nov., sp. nov. is proposed. The type strain of the type species is S9-650(T) ( = DSM 45627(T) = KACC 16232(T)).

Pseudonocardia antimicrobica sp. nov., a novel endophytic actinomycete associated with Artemisia annua L. (sweet wormwood).

A Gram-reaction-positive, non-motile, endophytic actinomycete, designated strain YIM 63235(T), was isolated from the surface-sterilized stems of Artemisia annua L., and characterized to determine its taxonomic position. The strain YIM 63235(T) formed well-differentiated aerial and substrate mycelia on media tested. The phylogenetic tree based on 16S rRNA gene sequences showed that the new isolate formed a distinct lineage within the genus Pseudonocardia, and the strain YIM 63235(T) was closely related to Pseudonocardia parietis 04-St-002(T) (99.1%). However, DNA-DNA relatedness demonstrated that strain YIM 63235(T) was distinct from the closest phylogenetic neighbor. The chemotaxonomic properties of strain YIM 63235(T) were consistent with those of the genus Pseudonocardia: the diagnostic diamino acid of the cell-wall peptidoglycan was meso-diaminopimelic acid and MK-8(H(4)) was the predominant menaquinone. The major fatty acids were iso-C(16:0) and iso-C(16:1) H. The DNA G+C content of strain YIM 63235(T) was 71.0 mol%. On the basis of the phenotypic and phylogenetic distinctiveness, the novel isolate was identified as representing a novel species of the genus Pseudonocardia, for which the name Pseudonocardia antimicrobica sp. nov. (type strain YIM 63235(T) =CCTCC AA 208080(T)=DSM 45303(T)) is proposed.

Colonization and movement of GFP-labeled Clavibacter michiganensis subsp. michiganensis during tomato infection.

The vascular pathogen Clavibacter michiganensis subsp. michiganensis is responsible for bacterial wilt and canker of tomato. Pathogenicity of this bacterium is dependent on plasmid-borne virulence factors and serine proteases located on the chromosomal chp/tomA pathogenicity island (PAI). In this study, colonization patterns and movement of C. michiganensis subsp. michiganensis during tomato infection was examined using a green fluorescent protein (GFP)-labeled strain. A plasmid expressing GFP in C. michiganensis subsp. michiganensis was constructed and found to be stable in planta for at least 1 month. Confocal laser-scanning microscopy (CLSM) of inoculated stems showed that the pathogen extensively colonizes the lumen of xylem vessels and preferentially attaches to spiral secondary wall thickening of the protoxylem. Acropetal movement of the wild-type strain C. michiganensis subsp. michiganensis NCPPB382 (Cmm382) in tomato resulted in an extensive systemic colonization of the whole plant reaching the apical region after 15 days, whereas Cmm100 (lacking the plasmids pCM1 and pCM2) or Cmm27 (lacking the chp/tomA PAI) remained confined to the area surrounding of the inoculation site. Cmm382 formed biofilm-like structures composed of large bacterial aggregates on the interior of xylem walls as observed by CLSM and scanning electron microscopy. These findings suggest that virulence factors located on the chp/tomA PAI or the plasmids are required for effective movement of the pathogen in tomato and for the formation of cellular aggregates.

Responses of environmental Amycolatopsis strains to copper stress.

Copper is a redox-active metal, which acts as a catalyst in the formation of Reactive Oxygen Species (ROS) encouraging oxidative stress. Protection against oxidants is intrinsic to every living cell; however, in stress conditions, cells are forced to increase and expand their antioxidative network. In this work, the novel copper-resistant strain Amycolatopsis tucumanensis and the copper-sensitive Amycolatopsis eurytherma were grown under copper increasing concentrations in order to elucidate the dissimilar effects of the metal on the strains viability, mainly on morphology and antioxidant capacity. Although biosorbed copper encouraged ROS production in a dose-dependent manner in both strains, the increase in ROS production from the basal level to the stress conditions in A. tucumanensis is lesser than in the copper-sensitive strain; likewise, in presence of copper A. eurytherma suffered inexorable morphological alteration while A. tucumanensis was not affected. The levels of antioxidant enzymes and metallothioneins (MT) were all greater in A. tucumanensis than in A. eurytherma; in addition MT levels as well as superoxide dismutase and thioredoxin reductase activities in A. tucumanensis, were higher as higher the concentration of copper in the culture medium. This work has given evidence that an efficient antioxidant defense system might aid microorganisms to survive in copper-stress conditions; besides it constitutes the first report of oxidative stress study in the genus Amycolatopsis and contributes to enlarge the knowledge on the copper-resistance mechanisms of A. tucumanensis.

In vitro antimicrobial properties of caprylic acid, monocaprylin, and sodium caprylate against Dermatophilus congolensis.

OBJECTIVE: To determine antimicrobial effects of caprylic acid and its derivatives, monocaprylin and sodium caprylate, on Dermatophilus congolensis and to determine effects of caprylic acid on the ultrastructure of D congolensis by use of transmission electron microscopy (TEM). SAMPLE: 3 strains of D congolensis (33411, 33413, and 14639). PROCEDURES: Strains of D congolensis were incubated separately under anaerobic conditions at 37°C for up to 48 hours in brain heart infusion (BHI) broth that was supplemented with various concentrations of caprylic acid (7.5, 12.5, 15, 17.5, or 20mM), monocaprylin (2.5, 5, 7.5, or 10mM), or sodium caprylate (15, 50, 60, 70, 100, or 120mM) or contained no antimicrobial treatment. After incubation, bacterial counts were determined by means of plating in triplicate on BHI-agar plates. Caprylic acid-treated or untreated D congolensis samples were embedded in epoxide resin for TEM; cross sections were examined for structural damage. RESULTS: Minimum inhibitory concentrations of caprylic acid, monocaprylin, and sodium caprylate against D congolensis were 7.5, 2.5, and 15 mM, respectively. Minimum bactericidal concentrations of caprylic acid, monocaprylin, and sodium caprylate against D congolensis were 15, 5, and 70 mM, respectively. Examination via TEM revealed that a 15-mM concentration of caprylic acid disintegrated the plasma membrane of D congolensis. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that caprylic acid, monocaprylin, and sodium caprylate could potentially be used to treat D congolensis infections. However, in vivo studies should be undertaken to determine whether these compounds can be considered as treatment options.

Emended description of the genus Actinokineospora Hasegawa 1988 and transfer of Amycolatopsis fastidiosa Henssen et al. 1987 as Actinokineospora fastidiosa comb. nov.

The species Amycolatopsis fastidiosa (ex Celmer et al. 1977) Henssen et al. 1987 was proposed, based on morphological and chemotaxonomic observations, for a strain originally described as 'Pseudonocardia fastidiosa' Celmer et al. 1977 in a US patent. In the course of a phylogenetic study of the taxa with validly published names within the suborder Pseudonocardineae based on 16S rRNA gene sequences, it became apparent that this species was misplaced in the genus Amycolatopsis. After careful evaluation of the phylogeny, morphology, chemotaxonomy and physiology of the type strain, it was concluded that this strain represents a species of the genus Actinokineospora that is unable to produce motile spores. The description of the genus Actinokineospora is therefore emended to accommodate species that do not produce motile spores, and it is proposed that Amycolatopsis fastidiosa be transferred to the genus Actinokineospora as Actinokineospora fastidiosa comb. nov. The type strain is NRRL B-16697(T) =ATCC 31181(T) =DSM 43855(T) =JCM 3276(T) =NBRC 14105(T) =VKM Ac-1419(T).

A case of Actinomycotic mycetoma involving the right foot.

A 45-year-old male presented with history of multiple swellings over the foot with sinuses discharging seropurulent pus. Actinomadura madurae was demonstrated and identified by microbiological culture from the pus obtained directly of the lesion. This case is reported to emphasize the importance of laboratory diagnosis in the management and assessment of the prognosis of such cases.

Nocardioides sediminis sp. nov., isolated from a sediment sample.

A strictly aerobic, motile, short-rod-shaped, Gram-positive-staining actinomycete strain, designated MSL-01(T), was isolated from a sediment sample from Bigeum Island of Korea. 16S rRNA gene sequence analysis revealed that the isolate MSL-01(T) belonged to the genus Nocardioides, with the highest sequence similarity to Nocardioides terrigena DS-17(T) (98.54 %), but the DNA-DNA relatedness to this type strain was 34 %. The physiological properties of strain MSL-01(T) differ from those of Nocardioides terrigena DS-17(T) and other species of Nocardioides. The diamino acid in the cell-wall peptidoglycan of strain MSL-01(T) is ll-diaminopimelic acid, the major menaquinone is MK-8(H(4)) and iso-C(16 : 0) is the major fatty acid component. The name Nocardioides sediminis sp. nov. is proposed for the novel species, with the type strain MSL-01(T) (=DSM 19263(T) =KCTC 19271(T)).

Microbacterium profundi sp. nov., isolated from deep-sea sediment of polymetallic nodule environments.

A Gram-positive, aerobic, neutrophilic and rod-shaped bacterium, strain Shh49(T), was isolated from a deep-sea sediment sample collected from the East Pacific polymetallic nodule region. The strain was able to grow within a temperature range of 4-35 degrees C and tolerated up to 7.5 % (w/v) NaCl. Strain Shh49(T) was characterized chemotaxonomically by having MK-12 and MK-13 as predominant isoprenoid quinones, anteiso-C(15 : 0), iso-C(15 : 0), iso-C(16 : 0) and anteiso-C(17 : 0) as major fatty acids and ornithine as cell-wall diamino acid. The genomic DNA G+C content was 66.8 mol%. On the basis of 16S rRNA gene sequence similarities, the closest phylogenetic neighbours were the type strains of Microbacterium phyllosphaerae (98.3 %) and Microbacterium keratanolyticum (98.0 %), but strain Shh49(T) could be clearly distinguished from its phylogenetic relatives with reference to a broad range of physiological and biochemical markers. DNA-DNA relatedness of strain Shh49(T) with M. phyllosphaerae DSM 13468(T) and M. keratanolyticum DSM 8606(T) was 56 and 31 %, respectively. On the basis of phenotypic and genotypic data presented in this study, strain Shh49(T) represents a novel species of the genus Microbacterium, for which the name Microbacterium profundi sp. nov. is proposed. The type strain is Shh49(T) (=CGMCC 1.6777(T) =JCM 14840(T)).

Copper bioaccumulation by the actinobacterium Amycolatopsis sp. AB0.

Amycolatopsis sp. AB0, a copper resistant actinobacterium isolated from polluted sediments, has shown high copper specific biopsortion ability (25 mg g(-1)). Two approaches were used to confirm metal accumulation in growing cells of Amycolatopsis sp. AB0; we performed subcellular fractioning assays which showed that the retained copper was associated with the extra-cellular fraction (exopolymer, 40%), but mainly within the cells. Intracellular distribution of copper was: 86% in the cytosolic fraction, 11% at the cell wall and 3% associated with the ribosome/membrane fraction. Its copper bioaccumulation ability was corroborated by using silver enhanced staining of copper with the Timm's reagent technique, which has not been used to detect metal deposits in bacteria before. In addition, we constructed specific oligonucleotides for targeting genes coding for copper P-Type ATPases that could be involved in the copper uptake ability of this strain. A 607 bp DNA fragment was amplified and sequenced from Amycolatopsis sp AB0. BLAST search analysis showed 71% protein homology of the deduced sequence with a putative cation-transporting ATPase of Nocardia farcinica and 65% with a copper translocating ATPase of Mycobacterium flavescens. To our knowledge this is the first report of the presence of copper P-type ATPase genes in the Amycolotopsis genus.

Fodinicola feengrottensis gen. nov., sp. nov., an actinomycete isolated from a medieval mine.

A filamentous, Gram-positive actinobacterium was isolated from acidic rocks in a medieval alum slate mine and was investigated by means of a polyphasic taxonomic approach. A 16S rRNA gene sequence similarity study indicated that strain HKI 0501(T) forms an individual line of descent and is related to certain members of the suborder Frankineae, order Actinomycetales (<95 % sequence similarity). Distance-matrix and neighbour-joining analyses set the branching point of the novel isolate between two clades, one being represented by members of the genus Cryptosporangium (family 'Kineosporiaceae') and the other by members of the genera Frankia and Acidothermus (family Frankiaceae and family Acidothermaceae, respectively). The organism had meso-diaminopimelic acid as the diagnostic diamino acid in the cell-wall peptidoglycan and xylose as the characteristic cell-wall sugar. The muramic acid in the peptidoglycan was found to be N-acetylated. The major menaquinones were MK-9(H(4)), MK-9(H(6)) and MK-9(H(8)) and the fatty acid profile was characterized by the predominance of iso-C(16 : 0), 10-methyl C(17 : 0), C(17 : 1) cis9 and 10-methyl iso-C(18 : 0). The polar lipids comprised diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylserine, phosphatidylinositol and several unknown phospholipids and glycolipids. Mycolic acids were absent. The DNA G+C content was 65 mol%. The distinct phylogenetic position and the phenotypic markers that clearly separate the novel organism from all other members of the suborder Frankineae indicate that strain HKI 0501(T) represents a novel genus and species, for which the name Fodinicola feengrottensis gen. nov., sp. nov. is proposed. The type strain of Fodinicola feengrottensis is HKI 0501(T) (=DSM 19247(T) =JCM 14718(T)).

Nocardiopsis valliformis sp. nov., an alkaliphilic actinomycete isolated from alkali lake soil in China.

A strain (HBUM 20028(T)) isolated from alkali lake soil in China was studied by a polyphasic taxonomic approach. The strain produced abundant aerial and substrate mycelia. Long spore chains were borne on the aerial mycelium, and the substrate mycelium was often arranged in a shape like a fence or palisade. The special characteristic of strain HBUM 20028(T) was its abundant growth under alkaline conditions, at pH 8.0-14.0. The cell wall of strain HBUM 20028(T) contained meso-diaminopimelic acid but no diagnostic sugar. Major phospholipids included diphosphatidylglycerol and phosphatidylcholine. The major menaquinones were MK-10(H(2)), MK-10(H(4)) and MK-10(H(6)). The major cellular fatty acids were iso-C(16 : 0) (31.66 %), anteiso-C(17 : 0) (14.85 %) and C(18 : 1)omega9c (14.73 %). All of these characters consistently indicated that strain HBUM 20028(T) belongs to the genus Nocardiopsis. DNA-DNA hybridization between the strain and type strains of related species gave relatedness values far below 70 %. Based on 16S rRNA gene sequence analysis, DNA relatedness and phenotypic characteristics, a novel species with the name Nocardiopsis valliformis sp. nov. is proposed. The type strain is HBUM 20028(T) (=DSM 45023(T) =CGMCC 4.2135(T)).

Humibacillus xanthopallidus gen. nov., sp. nov.

Strain KV-663(T) was isolated from a soil sample collected from a paddy field in Japan by using GPM agar plates. Strain YM21-029 was obtained from a lake sediment sample by using HSV agar. The two novel strains were Gram-positive, catalase-positive, rod-shaped bacteria with ll-diaminopimelic acid as the diagnostic diamino acid of the cell-wall peptidoglycan. The major menaquinone was MK-8(H(4)). Mycolic acids were not detected. The G+C content of the DNA was 69-70 mol%. 16S rRNA gene sequence analysis revealed that these strains represent a novel lineage within the family Intrasporangiaceae, order Actinomycetales, and are related to members of the genera Intrasporangium and Terracoccus. Based on morphological, biochemical and chemotaxonomic properties, together with phylogenetic analysis based on 16S rRNA gene sequences, the two new strains are considered to represent a novel species of a new genus, for which the name Humibacillus xanthopallidus gen. nov., sp. nov. is proposed. The type strain of the type species, Humibacillus xanthopallidus, is KV-663(T) (=NRRL B-24471(T)=NBRC 101803(T)).