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The geological structure and history of mountains often cause highly complex patterns of evolution. The origin and diversity of the genus Triplophysa is considered to be closely associated with the rapid and persistent rise of the Qinghai-Tibet Plateau (QTP). Species of the genus are widely distributed in the QTP and adjacent regions, and are strongly adapted to its extreme environments. However, the Central Chinese Mountains (CCM), which are far apart from the QTP, also have many Triplophysa populations and yet their taxonomy, phylogeny and origin are unknown. We used three mitochondrial genes of 266 individuals from 29 sites in the CCM to shed light on the evolution of these Triplophysa populations. Phylogenetic analyses and species delimitation revealed seven distinct molecular operational taxonomic units (mOTUs) in the CCM, each with low genetic diversity. Molecular clock and biogeographic analyses suggested that vicariance events resulting from the rapid uplifting of the Qinling and Taihang Mountains initialized diversification in the Pliocene. During the early Pleistocene, dispersal events in the central parts of the Yellow River drainage altered genetic diversity and led to the currently observed biogeographic patterns. Our results suggest the presence of at least six species of Triplophysa in the CCM and more are likely to be discovered in the future.

The effects of the oral administration of Rehmannia glutinosa polysaccharide (RGP-1) on the immunoregulatory properties, antioxidant activity, and resistance against Aeromonas hydrophila in Cyprinus carpio L. were investigated. The purified RGP-1 (250, 500, and 1,000 μg/mL) was co-cultured with the head kidney cells of the common carp. The proliferation and phagocytosis activities of the head kidney cells, and the concentration of nitric oxide (NO) and cytokines in the culture medium were determined. Next, 300 common carps (47.66 ± 0.43 g) were randomly divided into five groups; the two control groups (negative and positive) were administered sterile PBS and the three treatment groups were administered different concentrations of RGP-1 (250, 500, and 1,000 μg/mL) for seven days. Subsequently, the positive and treatment groups were infected with A. hydrophila, and the negative group was administered sterile PBS for 24 h. The concentration of NO, cytokines, lysozyme (LZM), and alkaline phosphatase (AKP) in serum, the total antioxidant capacity (T-AOC), the levels of malonaldehyde (MDA) and glutathione (GSH), and the total activities of superoxide dismutase (T-SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) in the hepatopancreas of the common carp were tested. We observed that RGP-1 could significantly enhance the proliferation and phagocytosis activities (P < 0.05), besides inducing the production of NO, pro-inflammatory cytokines (TNF-α, IL-1β, IL-6, IL-12) and anti-inflammatory cytokines (IL-10, TGF-β) (P < 0.05) in vitro. The in vivo experimental results revealed that RGP-1 significantly enhanced NO production, protein levels of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6, IL-12), LZM and AKP activities, and the antioxidant content (T-AOC, SOD, CAT, GSH, GSH-Px, and MDA) compared to that observed in the negative group prior to A. hydrophila infection (P < 0.05). NO, pro-inflammatory cytokines, LZM and AKP activities were significantly lower than that in the positive group after infection (P < 0.05). However, whether infected or not, the expression of anti-inflammatory cytokines (IL-10, TGF-β) increased significantly in the RGP-1-treated groups (P < 0.05). Therefore, the results suggested that RGP-1 could enhance the non-specific immunity, antioxidant activity and anti-A. hydrophila activity of the common carp, and could be used as a safe and effective feed additive in aquaculture.

A Streptomyces isolate, designated strain SYSU D8023T, was isolated from a desert sand sample collected from Gurbantunggut desert, China. The characterisation of the isolate was achieved using a polyphasic taxonomic approach. The isolate was found to be Gram-positive and aerobic. The strain was found to be able to grow at 14–50 °C, pH 6.0–9.0 and in the presence of up to 7% (w/v) NaCl. Strain SYSU D8023T contains LL-diaminopimelic acid as a cell wall diamino acid. The polar lipids were identified as diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannoside, an unidentified glycolipid and an unidentified phospholipid. MK-9(H6) and MK-9(H8) were detected as the respiratory quinones, and anteiso-C15:0, iso-C16:0 and anteiso-C17:0 as the predominant fatty acids. Pairwise comparison of the 16S rRNA gene sequences indicated that strain SYSU D8023T has a sequence identity of 97.9% to Streptomyces barkulensis RC 1831T. The DNA G + C content of strain SYSU D8023T was determined to be 70.1 mol%. Based on the analyses of the phenotypic, genotypic and phylogenetic characteristics, strain SYSU D8023T was concluded to represent a novel species of the genus Streptomyces, for which the name Streptomyces desertarenae sp. nov. is proposed. The type strain of the species is SYSU D8023T (= CGMCC 4.7455T = KCTC 49023T).

A novel actinobacterium, designated strain CFH 30205T, was isolated from a soil sample collected from a karst cave in Luoyang, Henan Province, China. The taxonomic position of the strain was investigated by using a polyphasic approach. Cells of the strain were aerobic, Gram-stain-positive, non-motile and rod-shaped. The strain was found to be catalase- and oxidase-positive. Strain CFH 30205T grew optimally at 28 °C, pH 9.0 and in the presence of up to 1.5 % NaCl (w/v). On the basis of 16S rRNA gene sequence analysis, strain CFH 30205T was most closely related to the type strains of Nocardioides terrigena DS-17T (97.6 % sequence similarity) and Nocardioides sediminis MSL-01T (97.0 %). The DNA G+C content was determined to be 69.9 mol%. ll-2,6-Diaminopimelic acid was the diagnostic diamino acid in the cell-wall peptidoglycan. The whole-cell sugars were mannose, xylose and galactose. The major isoprenoid quinone was MK-8 (H4), and the major fatty acids (>10 %) were iso-C16 : 0 and anteiso-C14 : 0. The polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and an unidentified phospholipid. On the basis of phenotypic, genotypic and phylogenetic data, strain CFH 30205T merits representation of a novel species of the genus Nocardioides , for which the name Nocardioides allogilvus sp. nov. is proposed. The type strain is CFH 30205T (=KCTC 49020T=CGMCC 4.7457T).

A Gram-stain-positive, aerobic and non-motile actinobacterial strain, designated YIM C0533T, was isolated from a soil sample collected from Shiling county, Yunnan province, south-west China. The isolate grew at 15–37 °C, pH 6.0–8.0 and in the presence of 0–3 % (w/v) NaCl. The whole-cell hydrolysates contained meso-diaminopimelic acid, xylose, galactose, mannose, ribose, arabinose, glucose and rhamnose. The acyl type of muramic acid was glycolyl. The polar lipids detected were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylmethylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside and an unidentified phospholipid. The major cellular fatty acids were iso-C16 : 0, 10-methyl C17 : 0 and iso-C15 : 0.MK-9(H6) was the predominant menaquinone. The genomic DNA G+C content was determined to be 69.4 mol%. These chemotaxonomic data and the morphological properties were consistent with those of the genus Hamadaea. The strain showed highest sequence similarities to Hamadaea tsunoensis CGMCC 4.1403T on phylogenetic analysis of 16S rRNA gene sequences and was found to form a coherent cluster in the neighbour–joining tree. The DNA–DNA hybridization experiment indicated that the DNA–DNA relatedness value between strain YIM C0533T and H. tsunoensis CGMCC 4.1403T was 34.4 ± 1.3 %. In addition, the results of physiological and biochemical tests allowed the isolate to be differentiated phenotypically from H. tsunoensis CGMCC 4.1403T. On the basis of data from this polyphasic study, strain YIM C0533T is characterized as a novel species of the genus Hamadaea, for which the name Hamadaea flava sp. nov. is proposed. The type strain is YIM C0533T ( = CPCC 204160T = KCTC 39591T = CGMCC 4.7289T). An emended description of the genus Hamadaea is also provided.

A slightly thermophilic, Gram-staining-negative and strictly aerobic bacteria, designated strain YIM 78141T, was isolated from a sediment sample collected at Hehua hot spring, Tengchong, Yunnan province, south-west China. Cells of the strain were short-rod-shaped and colonies were yellowish and circular. The strain grew at pH 6.0–10.0 (optimum, pH 8.0–9.0) and 10–55 °C (optimum, 40–50 °C). Phylogenetic analyses based on 16S rRNA gene sequence comparison demonstrated that strain YIM 78141T belongs to the family Neisseriaceae , and strain YIM 78141T also showed low levels of 16S rRNA gene sequence similarity (below 93.4 %) with all other genera in this family. The only quinone was ubiquinone 8 and the genomic DNA G+C content was 67.3 mol%. Major fatty acids (>5 %) were C12 : 0, C16 : 0, C18 : 1ω7c and summed feature 3. The polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylmethylethanolamine, phospholipids of unknown structure containing aminoglycophospholipid and three unidentified polar lipids. On the basis of the morphological, physiological and biochemical characteristics as well as genotypic data, this strain should be classified as a representative of a novel genus and species of the family Neisseriaceae , for which the name Crenobacter luteus gen. nov., sp. nov. is proposed. The type strain is YIM 78141T ( = BCRC 80650T = KCTC 32558T = DSM 27258T).

The present study was conducted to determine the effects of waterborne copper exposure on the lipid metabolism and intestinal microbiota of juvenile common carp (Cyprinus carpio L.). Common carp were exposed to four waterborne copper (Cu) concentrations (0 (control), 0.07 (low), 0.14 (medium), and 0.28 (high) mg Cu/L) for 8 weeks. Exposure to a high concentration of Cu had a negative effect on growth indices (weight gain rate (WGR) and specific growth rate (SGR)). The biochemical indices measured in serum (low-density lipoprotein (LDL) and triglycerides (TGs)) were significantly affected by exposure to medium concentration levels of Cu. The mRNA levels of lipogenic enzymes (acetyl-CoA carboxylase 1 (ACC-1) and fatty acid synthase (FAS)) and sterol-regulator element-binding protein-1 (SREBP-1) in liver tissue and tight binding protein genes (ZO-1 and occludin) in intestinal epithelial tissue were significantly downregulated in the 0.14 and 0.28 mg/L Cu treatment groups, accompanied by upregulated mRNA levels of lipolysis enzymes (lipoprotein lipase (LPL) and carnitine palmitoyl transferase 1 (CPT-1)) in the liver. The data also showed that the composition of intestinal microbiota was changed following Cu exposure and could alter the α-diversity and β-diversity. The abundances of few putative short-chain fatty acid (SCFA)-producing bacteria, including Allobaculum, Blautia, Coprococcus, Faecalibacterium, Roseburia, and Ruminococcus, decreased significantly. More specifically, Roseburia sequences were positively associated with lipogenic enzymes, total protein (TP), and TGs and negatively associated with lipolysis enzymes. Other sequences related to probiotics (Lactobacillus, Bacillus and Akkermansia) were also found to decrease, accompanied by an increase in sequences related to pathogens (Pseudomonas and Acinetobacter). To the best of our knowledge, the present study provides the first evidence that waterborne, chronic Cu exposure can disturb the composition of intestinal microbiota related to lipid metabolism and immunity in freshwater fish, thereby increasing the risk of pathogen invasion.

Strains YIM 77562T and YIM 77580, two novel Gram-staining-positive, filamentous bacterial isolates, were recovered from the Rehai geothermal field, Tengchong, Yunnan province, south-west China. Good growth was observed at 50–55 °C and pH 7.0. Aerial mycelium was absent on all media tested. Substrate mycelium was well-developed, long and moderately flexuous, and formed abundant, single, warty, ornamented endospores. Phylogenetic analysis of the 16S rRNA gene sequences of the two strains indicated that they belong to the family Thermoactinomycetaceae . Similarity levels between the 16S rRNA gene sequences of the two strains and those of type strains of members of the Thermoactinomycetaceae were 88.33–93.24 %; the highest sequence similarity was with Hazenella coriacea DSM 45707T. In both strains, the predominant menaquinone was MK-7, the diagnostic diamino acid was meso-diaminopimelic acid and the major cellular fatty acids were iso-C14 : 0, iso-C15 : 0 and iso-C16 : 0. The major polar lipids were diphosphatidylglycerol, phosphatidylmethylethanolamine, unidentified polar lipids and unidentified phospholipids. The genomic DNA G+C contents of strains YIM 77562T and YIM 77580 were 45.5 and 44.2 mol%, respectively. DNA–DNA relatedness data suggest that the two isolates represent a single species. Based on phylogenetic analyses and physiological and biochemical characteristics, it is proposed that the two strains represent a single novel species in a new genus, Geothermomicrobium terrae gen. nov., sp. nov. The type strain of Geothermomicrobium terrae is YIM 77562T ( = CCTCC AA 2011022T = JCM 18057T).

An alkalitolerant, thermotolerant and Gram-stain negative bacterium, designated strain YIM 78007T, was isolated from an alkaline geothermal soil sample from Hehua hot spring, Tengchong, Yunnan province, south-west China. Cells of strain YIM 78007T were observed to be aerobic and short rod-shaped. The colonies were observed to be orange-red, convex and circular. 16S rRNA gene sequence-based phylogenetic analysis showed that strain YIM 78007T clustered with members of the genus Roseomonas (with similarities from 97.2 to 92.2 %). Optimal growth of strain YIM 78007 occurs at 40–50 °C and pH 8.0–10.0. The predominant ubiquinone was identified as Q-10 and the major fatty acids were identified as C18:1 ω7c and C16:0. The polar lipids were identified as diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, two unidentified aminolipids and one unknown phospholipid. The G + C content of the genomic DNA was determined to be 63 mol %. The levels of DNA–DNA hybridization relatedness between strain YIM 78007T and its closet neighbours (Roseomonas lacus JCM 13283T and Roseomonas terrae JCM 14592T) were well below the threshold required for the proposal of a novel species. The results of physiological and biochemical characteristics, the phylogenetic analysis, as well as low DNA–DNA hybridization values, allowed the phenotypic and genotypic differentiation of strain YIM 78007T from its closest phylogenetic neighbours. Therefore, strain YIM 78007T is considered to represent a novel species of the genus Roseomonas, for which the name Roseomonas alkaliterrae sp. nov. is proposed. The type strain is YIM 78007T (=BCRC 80644T = JCM 19656T).

Bacterial strain 14-2AT, isolated from a long-term DDT-contaminated soil in China, was characterized by using a polyphasic approach to clarify its taxonomic position. Strain 14-2AT was found to be Gram-negative, aerobic, non-spore-forming, non-motile, non-flagellated and rod-shaped. The new isolate was able to grow at 4–42 °C, pH 6.0–9.0 and with 0–5 % NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the isolate belongs to the family Sphingobacteriaceae . The 16S rRNA gene sequence of strain 14-2AT showed the highest similarity with Olivibacter oleidegradans TBF2/20.2T (99.4 %), followed by Pseudosphingobacterium domesticum DC-186T (93.8 %), Olivibacter ginsengisoli Gsoil 060T (93.6 %), Olivibacter terrae Jip13T (93.1 %), Olivibacter soli Gsoil 034T (92.8 %) and Olivibacter sitiensis AW-6T (89.6 %). The DNA–DNA hybridization value between strains 14-2AT and O. oleidegradans TBF2/20.2T was 34.45±2.11 %. Strain 14-2AT contained phosphatidylethanolamine, phosphatidylmonomethylethanolamine, aminophospholipid and phosphatidylinositol mannoside as the major polar lipids. The DNA G+C content was 41.2 mol%. MK-7 is the major isoprenoid quinone. Summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c), iso-C15 : 0 and iso-C17 : 0 3-OH are the major fatty acids. The phenotypic and chemotaxonomic data confirmed the affiliation of strain 14-2AT to the genus Olivibacter . On the basis of the phylogenetic and phenotypic characteristics, and chemotaxonomic data, strain 14-2AT is considered to represent a novel species of the genus Olivibacter , for which the name Olivibacter jilunii sp. nov. is proposed; the type strain is 14-2AT ( = KCTC 23098T = CCTCC AB 2010105T).

A novel cold-resistant bacterium, designated YIM 016(T), was isolated from a peat bog sample collected from Mohe County, Heilongjiang Province, Northern China and its taxonomic position was investigated using a polyphasic approach. The strain was Gram-positive, aerobic, endospore-forming, motile and rod-shaped. Phylogenetic analyses based on the 16S rRNA gene sequence clearly revealed that strain YIM 016(T) is a member of the genus Paenibacillus. The strain is closely related to Paenibacillus alginolyticus DSM 5050(T), Paenibacillus chondroitinus DSM 5051(T) and Paenibacillus pocheonensis Gsoil 1138(T) with similarities of 99.0 %, 97.0 % and 96.3 %, respectively. Meanwhile, the low DNA-DNA relatedness levels between strain YIM 016(T) and its closely related phylogenetic neighbours demonstrated that this isolate represents a new genomic species in the genus Paenibacillus. Phenotypic and chemotaxonomic tests showed that growth of strain YIM 016(T) occurred at 4-37 °C, pH 6.0-8.0 and with a NaCl tolerance up to 0.5 % (w/v). The peptidoglycan contained meso-diaminopimelic acid, alanine and glutamic acid. The whole-cell hydrolysates mainly contained glucose, galactose and ribose. The predominant menaquinone was MK-7 and the major fatty acids were anteiso-C(15:0) and iso-C(16:0). The DNA G+C content of strain YIM 016(T) was 51.7 mol %. On the basis of phylogenetic, phenotypic and chemotaxonomic characteristics, strain YIM 016(T) could be clearly distinguished from other species of the genus Paenibacillus. It is therefore concluded that strain YIM 016(T) represents a novel species in the genus Paenibacillus, for which the name Paenibacillus frigoriresistens sp. nov. is proposed. The type strain is YIM 016(T) (= CCTCC AB 2011150(T) = JCM 18141(T)).

An orange-coloured, non-spore-forming, motile and coccus-shaped actinobacterium, designated YIM 75677(T), was isolated from a soil sample collected from a dry-hot river valley in Dongchuan county, Yunnan Province, south-west China and its taxonomic position was investigated. Growth of strain YIM 75677(T) occurred at 12-55 °C, pH 6.0-9.0 and NaCl tolerance up to 2 % (w/v). Cells adhered to agar media and were agglutinated tightly together. The peptidoglycan contained meso-diaminopimelic acid, alanine and glutamic acid. The whole-cell hydrolysates mainly contained glucose, galactose, mannose and ribose. The predominant menaquinone was MK-9 (H(2)) and the major fatty acids were anteiso-C(15:0) and iso-C(15:0). Mycolic acids were not present. The DNA G+C content of strain YIM 75677(T) was 74.8 mol%. Phylogenetic analyses based on 16S rRNA gene sequence comparisons clearly revealed that strain YIM 75677(T) represents a novel member of the genus Kineococcus and is closely related to Kineococcus xinjiangensis S2-20(T) (level of similarity, 98.6 %). Meanwhile, the result of DNA-DNA hybridization between strain YIM 75677(T) and K. xinjiangensis S2-20(T) demonstrated that this isolate represented a different genomic species in the genus Kineococcus. On the basis of phylogenetic, phenotypic and chemotaxonomic characteristics, strain YIM 75677(T) represents a novel species of the genus Kineococcus, for which the name Kineococcus glutineturens sp. nov. is proposed. The type strain is YIM 75677(T) (=CCTCC AA 209075(T) = JCM 18126(T)).

A novel actinobacterium, designated MBRL 201(T), was isolated from a sample collected from a limestone quarry at Hundung, Manipur, India. The strain was characterized using polyphasic taxonomy. Comparison of the 16S rRNA gene sequence of strain MBRL 201(T) and other Streptomyces species showed sequence similarities ranging from 93.0 to 99.6 % and strain MBRL 201(T) showed closest similarities to Streptomyces virginiae NBRC 12827(T) (99.6 %) and Streptomyces cinnamonensis NBRC 15873(T) (99.6 %). The DNA relatedness between MBRL 201(T) and the type strains of S. virginiae NBRC 12827(T) and S. cinnamonensis NBRC 15873(T) were 44.5 and 35.6 % respectively. Strain MBRL 201(T) contained LL: -diaminopimelic acid (A(2)pm) as the diagnostic diamino acid, with glucose as the main sugar, while small amounts of galactose, glucose, mannose, rhamnose, ribose and xylose were also present in cell-wall hydrolysates. The major fatty acids identified were anteiso-C(15:0) (38.9 %), iso-C(15:0) (19.9 %) and anteiso-C(17:1) (14.7 %). The predominant menaquinones detected were MK-9(H(6)) and MK-9(H(8)), while the polar lipids were diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositolmannosides, with other unknown phospholipids and lipids. The G+C content of the genomic DNA was 72.9 %. The phenotypic and genotypic data showed that strain MBRL 201(T) merits recognition as a representative of a novel species of the genus Streptomyces. It is proposed that the isolate should be classified in the genus Streptomyces as a novel species, Streptomyces manipurensis sp. nov. The type strain is MBRL 201(T) (=DSM 42029(T) = JCM 17351(T)).

A xylanase gene (thxyn11A) from the Thermobifida halotolerans strain YIM 90462T was cloned and expressed in Escherichia coli. The open reading frame (ORF) of thxyn11A has 1,008 bp encoding a mature xylanase with a high degree of similarity (80 %) to the xylanase from Nocardiopsis dassonvillei subsp. dassonvillei DSM 43111. This enzyme (Thxyn11A) also possesses a glycosyl hydrolases family 11 (GH11) domain and a high isoelectric point (pI = 9.1). However, Thxyn11A varies from most GH11 xylanases, due to its large molecular mass (34 kDa). Recombinant Thxyn11A demonstrated a strong pH and temperature tolerance with a maximum activity at pH 9.0 and 70 °C. Xylotriose, the end-product of xylan hydrolysis by Thxyn11A, serves as a catalyst for hemicellulose pretreatment in industrial applications and can also function as a food source or supplement for enterobacteria. Due to its attractive biochemical properties, Thxyn11A may have potential value in many commercial applications.

Two closely related thermophilic bacterial strains, designated YIM 71031(T) and YIM 71039, were isolated from a hot spring in Tengchong county, Yunnan province, south-western China. The novel isolates were observed to be Gram-negative, aerobic, rod-shaped and yellow-pigmented bacteria. The strains were found to be able to grow at 37-65 °C, pH 6.0-9.0 and with a NaCl tolerance up to 1.0 % (w/v). Phylogenetic analysis based on 16S rRNA gene sequences placed these two isolates in the genus Meiothermus. They were found to be closely related to Meiothermus timidus DSM 17022(T) (98.6 % similarity), and formed a cluster with this species. The predominant menaquinone was identified as MK-8 and the major fatty acids (>10 %) as anteiso-C15:0, iso-C15:0, anteiso-C17:0, iso-C16:0 and C16:0. The genomic DNA G+C contents of strains YIM 71031(T) and YIM 71039 were determined to be 64.0 and 65.4 mol%, respectively. DNA-DNA hybridizations showed low values between strains YIM 71031(T) and YIM 71039 and their closely related neighbour M. timidus DSM 17022(T). Morphological phylogenetic and chemotaxonomic results suggest that strains YIM 71031(T) and YIM 71039 are representatives of a new species within the genus Meiothermus, for which the name Meiothermus roseus sp. nov. is proposed. The type strain is YIM 71031(T) (=KCTC 42495(T) =NBRC 110900(T)).

A Gram-staining negative, rod-shaped bacterium, designated strain YIM 78110T, was isolated from a sediment sample collected from Hehua hot spring in Tengchong, Yunnan province, south-west China. The taxonomic status of strain YIM 78110T was confirmed by a polyphasic approach. 16S rRNA gene sequence analysis indicated that strain YIM 78110T belongs to the genus Cecembia, displaying 96.8 % and 94.7 % sequence similarity with the two most closely related type strains, Cecembia calidifontis RQ-33T and Cecembia lonarensis LW9T, respectively. The low value of DNA–DNA hybridization (52.3 ± 2.3 %) between strain YIM 78110T and its closest neighbour, Cecembia calidifontis RQ-33T, indicated that this new isolate represented a different genomic species in the genus Cecembia. The temperature for growth ranged from 30 to 50 °C. The pH for growth ranged from pH 4.0 to 10.0, with NaCl tolerance of 0.5–6.0 % (w/v). The predominant menaquinone of strain YIM 78110T was MK-7 and the major polar lipid was phosphatidylethanolamine. The major fatty acids were iso-C15:0 and C15:0. The DNA G+C content was 47.1 mol%. On the basis of physiological, biochemical and phylogenetic analyses, it is proposed that strain YIM 78110T represents a novel species of the genus Cecembia, for which the name Cecembia rubra sp. nov. is proposed. The type strain is YIM 78110T ( = CCTCC AB2013287T = DSM 28057T).

A novel endoglucanase gene was cloned from Thermobifida halotolerans YIM 90462T, designated as thcel6A for being a member of glycoside hydrolase family 6. The gene was 1332 bp long and encoded a 443-amino-acid protein with a molecular mass of 45.9 kDa. The purified recombinant endoglucanase had optimal activity at 55 °C and pH 8.5. Thcel6A showed high hydrolytic activities at 25–55 °C and retained 58 % of initial activity after incubation at 90 °C for 1 h. It retained more than 80 % of activity after incubation for 12 h at pH values from 4 to 12. Thcel6A displayed higher hydrolytic activities in 5–15 % NaCl (w/v) than at 0 % NaCl. Activity increased 2.5-fold after incubation with 20 % (w/v) NaCl at 37 °C for 10 min. These properties suggest that this novel endoglucanase has potential for specific industrial application.

A Gram-positive, aerobic, nonmotile actinomycete strain designated DRQ-2(T) was isolated from the soil sample collected from lime-stone open pit mine from the Gulbarga region, Karnataka province, India. Strain DRQ-2(T) was identified as a member of the genus Nonomuraea by a polyphasic approach. Strain DRQ-2(T) could be differentiated from other members of the genus Nonomuraea on the basis of physiology and 16S rRNA gene sequence analysis. The 16S rRNA gene sequence similarity of strain DRQ-2(T) showed highest sequence similarity to Nonomuraea muscovyensis DSM 45913(T) (99.1%), N. salmonea DSM 43678(T) (98.2%) and N. maheshkhaliensis JCM 13929(T) with 98.0%, respectively. Chemotaxonomic properties showing predominant menaquinones of MK-9 (H4), MK-9(H2) and MK-9(H6), major polar lipids comprised diphosphatidylglycerol, phosphatidylmono methyl ethanolamine (PME), phosphatidylethanolamine (PE), hydroxy-PME (OH-PME), hydroxy PE (OH-PEE), phosphatidylglycerol (PG), ninhydrin-positive phosphoglycolipid and unknown phospholipid, fatty acids with major amounts of i-C16:0, ai-C15:0 and ai-C17:0 supported allocation of the strain to the genus Nonomuraea. Results of DNA-DNA hybridization and physiological tests allowed genotypic and phenotypic differentiation of strain DRQ-2(T) from closely related species. The genomic DNA G+C content of the organism was 72.5 mol%. On the basis of phenotypic, chemotypic and molecular characteristics, strain DRQ-2(T) represents a novel species of the genus Nonomuraea, for which the name N. indica sp. nov. is proposed, with type strain DRQ-2(T) (=NCIM 5480(T)= CCTCC AA 209050(T)).

A Streptomyces-like actinomycete strain, designated as YIM 78087(T), was isolated from a sediment sample collected from Hehua hot spring in Tengchong, Yunnan province, south-west China. The taxonomic position of strain YIM 78087(T) was investigated by a polyphasic approach. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain YIM 78087(T) belongs to the genus Streptomyces and is closely related to Streptomyces fimbriatus DSM 40942(T), Streptomyces marinus DSM 41968(T) and Streptomyces qinglanensis DSM 42035(T) (97.18, 97.05 and 97.1 % similarity, respectively). Combined with the low values of DNA-DNA hybridization between strain YIM 78087(T) and its closest neighbours, these analyses indicated that this new isolate represents a different genomic species in the genus Streptomyces. The predominant menaquinones of strain YIM 78087(T) were identified as MK-9 (H4) and MK-9 (H6). The major fatty acids were identified as anteiso-C15:0 (28.4 %), anteiso-C17:0 (23.0 %) and iso-C16:0 (15.1 %). The whole-cell hydrolysates found to contain glucose, mannose and ribose. The DNA G+C content was determined to be 73.0 mol%. Based on the comparative analysis of phenotypic and genotypic characteristics, it is proposed that strain YIM 78087(T) represents a novel species of the genus Streptomyces, for which the name Streptomyces calidiresistens sp. nov., is proposed. The type strain is YIM 78087(T) (=BCRC 16955(T)=DSM 42108(T)=JCM 19629(T)).

An alkalitolerant, thermotolerant, strictly aerobic and Gram-staining negative bacterial strain, designated YIM 78140(T), was isolated from a water sample in Hehua hot spring, Tengchong, Yunnan province, south-west China. The colonies were light brown, convex and circular. Phylogenetic analysis of the 16S rRNA gene sequence of strain YIM 78140(T) indicated that it was clustered with members of β-Proteobacteria (with the similarity from 96.9 to 93.6 %). Good growth occurred at 40-50 °C, pH 8.0-9.0 and in the presence of 0-3 % (w/v) NaCl. The predominant ubiquinones were Q-8 and Q-9. The major fatty acids were C16:0, C17:0 cyclo, C18:1 ω7c and summed feature 3. The G+C content of genomic DNA was 70.8 mol%. The results of physiological and biochemical characteristics, phylogenetic analysis allowed the phenotypic and genotypic differentiation of strain YIM 78140(T) from its closest phylogenetic neighbours. Therefore, the strain YIM 78140(T) represents a novel genus of the family Comamonadaceae, for which the name Zhizhongheella caldifontis gen. nov., sp. nov. is proposed. The type strain is YIM 78140(T) (= BCRC 80649(T) = KCTC 32557(T)).

Two thermophilic bacterial strains, designated YIM 77925T and YIM 77777, were isolated from two hot springs, one in the Hydrothermal Explosion (Shuirebaozhaqu) area and Frog Mouth Spring in Tengchong county, Yunnan province, south-western China. The taxonomic positions of the two isolates were investigated by a polyphasic approach. Cells of the two strains were Gram-stain-negative, aerobic and rod-shaped. They were able to grow at 50–70 °C, pH 6.0–8.0 and with a NaCl tolerance up to 0.5 % (w/v). Colonies are circular, convex, non-transparent and produce yellow pigment. Phylogenetic analyses based on 16S rRNA gene sequences comparison clearly demonstrated that strains YIM 77925T and YIM 77777 represent members of the genus Thermus , and they also detected low-level similarities of 16S rRNA gene sequences (below 97 %) compared with all other species in this genus. Their predominant menaquinone was MK-8. The genomic DNA G+C contents of strains YIM 77925T and YIM 77777 were 65.6 mol% and 67.2 mol%, respectively. Based on the results of physiological and biochemical tests and phylogenetic analyses, strains YIM 77925T and YIM 77777 could not be classified as representing any species of the genus Thermus with a validly published name. Thus the two strains are considered to represent a novel species of the genus Thermus , for which the name Thermus caliditerrae sp. nov. is proposed. The type strain is YIM 77925T ( = DSM 25901T = CCTCC 2012061T).

Two novel Gram-positive, spore-forming, thermophilic actinomycetes, designated as strain YIM 77501(T) and YIM 77570, were isolated from a sandy soil sample collected at Tengchong National Volcanic Geological Park, Yunnan province, south-west China. Phylogenetic analysis based on the 16S rRNA gene sequences suggested that the two isolates fell within the family Streptosporangiaceae. The strains formed extensively branched substrate and aerial mycelia which carried masses of long, straight or irregular spore chains composed of warty ornamented spores. Cell walls of the two strains contained meso-diaminopimelic acid and glucose, galactose, mannose and ribose were detected as whole-cell sugars. The predominant menaquinones were MK-9(H(4)) and MK-9(H(6)). The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, N-acetylglucosamine-containing phospholipids and phosphatidylinositol, phosphatidylinositolmannosides. The major cellular fatty acids were iso-C(16:0) and 10-methyl C(17:0). The DNA G+C content was 74-76 mol%. On the basis of the morphological and chemotaxonomic characteristics as well as the phylogenetic analysis, these strains represents a novel species of a new genus within the family Streptosporangiaceae, for which the name Thermoactinospora rubra gen. nov., sp. nov. is proposed. The type strain of T. rubra is YIM 77501(T) (=DSM 45614(T) = CCTCC AA 2011014(T)).

A novel actinomycete strain, designated YIM 75904T, was isolated from a soil sample that had been collected from a dry and hot river valley in Dongchuan county, Yunnan province, south-western China. The taxonomic position of the novel strain was investigated by a polyphasic approach. In phylogenetic analyses based on 16S rRNA gene sequences, strain YIM 75904T formed a distinct clade within the genus Amycolatopsis and appeared to be closely related to Amycolatopsis sacchari K24T (99.3 % sequence similarity). Strain YIM 75904T had a type-IV cell wall, with no detectable mycolic acids, and had MK-9(H4) as its predominant menaquonine. Its cell wall contained meso-diaminopimelic acid, galactose, glucose and arabinose, and its major cellular fatty acids were iso-C16 : 0, iso-C15 : 0, anteiso-C17 : 0 and anteiso-C15 : 0. The genomic DNA G+C content of the novel strain was 68.5 mol%. Based on the results of physiological and biochemical tests and DNA–DNA hybridizations, strain YIM 75904T represents a novel species of the genus Amycolatopsis for which the name Amycolatopsis dongchuanensis sp. nov. is proposed. The type strain is YIM 75904T ( = CCTCC AA 2011016T = JCM 18054T).

A novel Gram-positive, aerobic, spore-forming, thermophilic actinomycete, designated strain YIM 77521T, was isolated from a sandy soil sample collected at Rehai National Park, Tengchong, Yunnan province, south-west China. The strain formed branched substrate mycelia and no fragmentation was found. Masses of short, straight or irregular chains of three to eight warty ornamented spores were borne from aerial mycelia. The strain contained meso-diaminopimelic acid in the cell wall and the whole-cell sugars contained mannose, galactose, glucose and ribose. The predominant menaquinones were MK-9(H4), MK-9(H6) and MK-9(H8). The diagnostic polar lipids were diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylethanolamine, hydroxyphosphatidylmonomethylethanolamine and N-acetylglucosamine-containing phospholipids. The major fatty acids were iso-C16 : 0, C17 : 0 10-methyl and C18 : 0. The DNA G+C content of strain YIM 77521T was 73.3 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain YIM 77521T fell within the radiation of the suborder Streptosporangineae and formed a distinct monophyletic lineage adjacent to the family Streptosporangiaceae with a high bootstrap value. On the basis of combined data from the phenotypic and phylogenetic analyses, strain YIM 77521T represents a novel genus and species within the family Streptosporangiaceae , for which the name Thermocatellispora tengchongensis gen. nov., sp. nov. is proposed. The type strain is YIM 77521T ( = DSM 45615T = CCTCC AA 2011013T).

A novel actinomycete, designated as strain YIM 75980(T), was isolated from a soil sample collected from a dry-hot river valley in Dongchuan county, Yunnan province, south-west China and was subjected to polyphasic taxonomic characterization. The organism produced circular, smooth, red to black coloured colonies comprising coccoid-shaped cells. Colonies on agar medium lacked mycelia and cells adhered to the agar. Strain YIM 75980(T) contained meso-diaminopimelic acid as the diagnostic diamino acid in the cell-wall peptidoglycan and contained galactose, arabinose and glucosamine as the main sugars in the whole-cell hydrolysates. The predominant menaquinone was MK-9 (H(4)) and the major fatty acids were iso-C(15:0), iso-C(16:0) and C(16:0). The DNA G + C content of strain YIM 75980(T) was 73.1 mol%. Phylogenetic analyses based on 16S rRNA gene sequences clearly showed that strain YIM 75980(T) formed a distinct clade within the genus Geodermatophilus and was closely related to Geodermatophilus obscurus DSM 43160(T) (level of similarity, 97.9%). Furthermore, the result of DNA-DNA hybridization between strain YIM 75980(T) and G. obscurus 43160(T) demonstrated that this isolate represented a different genomic species in the genus Geodermatophilus. Moreover, the physiological and biochemical data showed the differentiation of strain YIM 75980(T) from its closest phylogenetic neighbour. Therefore, it is proposed that strain YIM 75980(T) represents a novel species of the genus Geodermatophilus, for which the name Geodermatophilus nigrescens sp. nov. is proposed. The type strain is YIM 75980(T) (=CCTCC AA 2011015(T) =JCM 18056(T)).

A novel Gram-stain positive, aerobic, non-motile, spore-forming actinobacterium, designated YIM 75926(T), was isolated from a soil sample collected at soil forest in Yuanmo county of Yunnan province, south-west China. Its taxonomic position was investigated by a polyphasic approach. Phylogenetic analyses based on 16S rRNA gene sequences showed that the novel strain YIM 75926(T) belongs to the genus Pseudonocardia and was closely related to Pseudonocardia halophobica DSM 43089(T) (98.1% similarity). Strain YIM 75926(T) had MK-8 (H(4)) as the predominant menaquinone. The whole organism hydrolysates mainly consisted of meso-diaminopimelic acid, mannose, glucose, galactose and arabinose. The major cellular fatty acids were iso-C(16:0) (37.16%) and C(16:0) (12.43%). The DNA G+C content of strain YIM 75926(T) was 70.6 mol%. The resultant phylogenetic trees further showed that strain YIM 75926(T) belong to Pseudonocardia and had a distinct subclade within the evolutionary radiation of the genus Pseudonocardia. On the basis of its comparative analysis of phenotypic and genotypic characteristics, it is proposed that strain YIM 75926(T) represent a novel species of the genus Pseudonocardia, named Pseudonocardia yuanmoensis sp. nov. The type strain is YIM 75926(T) (=CCTCC AA 2011017(T) = JCM 18055(T)).

In this study, the taxonomic position of an actinobacterium, strain YIM M 10931T, which was isolated from a mangrove sediment sample collected in Dugong Creek, Little Andaman, India, was determined by a polyphasic approach. This Gram-positive, aerobic strain produced branched substrate mycelium and aerial hyphae, which differentiated into short, hooked or spiral spore chains. The organism contained meso-diaminopimelic acid as the diagnostic diamino acid in the cell-wall peptidoglycan. The whole cell sugars consisted of mannose, ribose, glucose, galactose and madurose. The cellular fatty acid profile mainly consisted of iso-C16 : 0, 10-methyl C18 : 0 and C16 : 0. The quinone system was predominantly composed of MK-9(H8) (45.5 %) and MK-9(H6) (39 %). The phospholipids detected were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol mannoside, phosphatidylinositol and two unknown phospholipids. The organism showed a combination of morphological and chemotaxonomic properties typical of members of the genus Actinomadura . Moreover, phylogenetic analysis based on a 16S rRNA gene sequence generated from the strain identified its closest relatives as Actinomadura cremea DSM 43676T (98.4 % sequence similarity), Actinomadura rifamycini DSM 43936T (97.4 %) and Actinomadura apis IM17-1T (96.9 %). It was obvious from the resulting phylogenetic trees that strain YIM M 10931T belongs to a distinct subclade within the evolutionary radiation of the genus Actinomadura . DNA–DNA hybridizations of strain YIM M 10931T with A. cremea DSM 43676T and A. rifamycini DSM 43936T were performed and further confirmed that the isolate represents a separate genomic species. Based on the phenotypic and genotypic characteristics presented, it is proposed that strain YIM M 10931T represents a novel species within the genus Actinomadura , for which the name Actinomadura sediminis sp. nov. is proposed; the type strain is YIM M 10931T ( = CCTCC AA 2010009T = DSM 45500T).

Aminopeptidase N is a member of the peptidase M1 family, and plays an important role in the digestion of protein. In this study, a full-length cDNA of APN gene was cloned from Ctenopharyngodon idellus with RT-PCR and RACE techniques, and its mRNA expression profile at different tissues was ana-lyzed by real-time PCR method. The full-length of cDNA sequence of APN had 3 258 nucleotides, includ-ing 27 nucleotides at 5’UTR and 552 nucleotides at 3’UTR. Its open reading frame(ORF) had 2 679 nu-cleotides encoding a 892-amino-acid peptide. The deduced amino acid sequences of APN gene from C. idellus displayed the highest similarity with Danio rerio (75.4%), but varied to other animals from 61.2% to 58.8%. The encoded protein molecular weight was predicted at 100.61 ku with pI at 5.14. Phylogenetic analysis showed that the sequence of APN gene was clustered with D. rerio as its closest neighbor, which shared a sequence similarity of 81.5%, and had lower similarity with other animals from 60.2% to 54.3%. The APN protein had one helix trans-membrane region, but its amino acid sequence of the region demon-strated a low homology relationship to other vertebrates. The abundances of APN mRNA assayed by real-time PCR were differentially expressed at different tissues with a gradient from higher to lower among the tissues of fore-intestine, hind-intestine, liver, mid-intestine, kidney, muscle, spleen and heart, respec-tively. However, the APN mRNA expression was relatively stable after incubation for 4 days. The effects of the circadian rhythms on APN expression of C. idellus showed that there was a time-dependent pattern at higher rhythm during 06:00-18:00 and lower rhythm during 18:00-06:00. Therefore, our study could serve as an important research tool to study the relationship between APN gene’s function and its structure, and investigate its molecular mechanism for protein degradation in vivo.