Repellency and toxicity of a CO2-derived cedarwood oil on hard tick species (Ixodidae).

The repellency and toxicity of a CO2-derived cedarwood oil (CWO) was evaluated against actively questing unfed nymphs of four species of hard ticks: Amblyomma americanum (L.), Dermacentor variabilis (Say), Ixodes scapularis Say, and Rhipicephalus sanguineus (Latreille). Using a vertical climb bioassay for repellency, nymphs of these species avoided a CWO-treated filter paper in proportional responses to treatment concentrations. At 60 min of exposure, I. scapularis nymphs were most sensitive with 50% repellency concentration (RC50) of 19.8 µg cm-2, compared with RC50 of 30.8, 83.8 and 89.6 µg cm-2 for R. sanguineus, D. variabilis and A. americanum, respectively. Bioassays determined the lethal concentration for 50% (LC50) and 90% (LC90) mortality of nymphs exposed to CWO in treated vials after 24- and 48-h exposure. After 24 h exposure, the LC50 values were 1.25, 3.45 and 1.42 µg cm-2 and LC90 values were 2.39, 7.59 and 4.14 µg cm-2 for D. variabilis, I. scapularis and R. sanguineus, respectively, but had minimal effect on A. americanum. After 48 h exposure, the LC50 values were 4.14, 0.78, 0.79 and 0.52 µg cm-2, and LC90 values were 8.06, 1.48, 1.54 and 1.22 µg cm-2 for A. americanum, D. variabilis, I. scapularis and R. sanguineus, respectively. The repellency of CWO on tick species decreased with time. The repellency and toxicity bioassays demonstrated concentration-dependent responses of tick nymphs to the oil, indicating the potential of the CO2-derived cedarwood oil be developed as an eco-friendly repellent and/or acaricide.

Methylobacterium segetis sp. nov., a novel member of the family Methylobacteriaceae isolated from soil on Jeju Island.

A bacterial strain, 17J42-1T, was isolated from a soil sample collected on Jeju Island, Republic of Korea. Colonies grown on R2A agar were pink in color, and cells were Gram-stain negative, short and rod-shaped. Analysis of 16S rRNA gene sequences identified this strain as a member of the genus Methylobacterium in the family Methylobacteriaceae, with high levels of 16S rRNA sequence similarity shared with Methylobacterium oxalidis 35aT (98.6%), Methylobacterium jeotgali S2R03-9T (97.5%), and Methylobacterium soli YIM 48816T (97.3%). Cells grew at 15-35 °C, pH 5-9, and in the presence of 0-1.0% NaCl. The genomic G + C content was 70.2 mol% based on the whole genome analysis. The predominant respiratory quinone was ubiquinone Q-10, the major fatty acid was C18:1ω7c (85.3%), and the major polar lipids were phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, and diphosphatidylglycerol. The phenotypic and chemotaxonomic data support the affiliation of strain 17J42-1T with the genus Methylobacterium. However, the DNA-DNA relatedness between the isolate and its closest phylogenetic neighbors was lower than 38%. The OrthoANI and dDDH values between strain 17J42-1T and the closest type strain Methylobacterium oxalidis NBRC 107715T were calculated to be 85.9% and 30.6%, respectively. The results of 16S rRNA gene sequence similarity analysis, DNA-DNA hybridization analysis, and the observed differentiating phenotypic properties from other closely related taxa clearly indicate that strain 17J42-1T represents a novel species in the genus Methylobacterium, for which the name Methylobacterium segetis sp. nov. is proposed. The type strain is 17J42-1T (= KCTC 62267T = JCM 33059T).

Emticicia agri sp. nov., a novel member of the family Cytophagaceae.

A bacterial strain, 17J42-9T, was isolated from a soil sample collected on Jeju Island, Republic of Korea. Cells were observed to be Gram-stain negative and rod-shaped. Colonies were observed to be orange in colour on R2A agar. Analysis of 16S rRNA gene sequences showed that high levels of 16S rRNA sequence similarity were shared between 17J42-9T and Emticicia fontis IMCC1731T (98.2 %), Emticicia ginsengisoliGsoil 085T (98.2 %) and Emticicia soli ZZ-4T (97.8 %). Growth of strain 17J42-9T was observed at 10-37 °C, pH 6.0-8.5 and in the presence of 0-0.5 % NaCl. The genomic G+C content was calculated to be 38.6 mol%. The predominant respiratory quinone of the isolate was found to be MK-7; the major fatty acids were identified as summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c) (34.1 %), C15 : 0iso (23.4 %) and C17 : 0iso 3-OH (10.8 %). The major polar lipids were found to be phosphatidylethanolamine, two unidentified aminolipids and an unidentified lipid. The phenotypic and chemotaxonomic data support the affiliation of strain 17J42-9T with the genus Emticicia. However, the DNA-DNA relatedness between the isolate and its closest phylogenetic neighbours was lower than 46 %. The results of 16S rRNA gene sequence similarity analysis, DNA-DNA hybridization analysis and the observed differentiating phenotypic properties from other closely related taxa clearly indicate that strain 17J42-9T represents a novel species in the genus Emticicia, for which the name Emticiciaagri sp. nov. is proposed. The type strain is 17J42-9T (=KCTC 62270T=JCM 33056T).

Mucilaginibacter terrigena sp. nov. sp., A Novel Member of the Family Sphingobacteriaceae.

A bacterial strain, 17JY9-4T, was isolated from a soil sample collected on Jeju Island, South Korea. Colonies grown on R2A agar are pale pink in color, and cells are Gram-stain negative, short, and rod-shaped. Analysis of 16S rRNA gene sequences identified this strain as a member of the genus Mucilaginibacter in the family Sphingobacteriaceae, with high levels of 16S rRNA sequence similarity shared with Mucilaginibacter lutimaris BR-3T (98.0%), Mucilaginibacter rigui WPCB133T (98.0%), Mucilaginibacter phyllosphaerae PP-F2F-G21T (97.0%), Mucilaginibacter amnicola TAPP7T (96.8%), and Mucilaginibacter soli R9-65T (96.7%). Growth of strain 17JY9-4T occurs at 10-30 °C, pH 6-8, and in the presence of 0-1.0% NaCl. The genomic G+C content is 44.38 mol%. The predominant respiratory quinone of the isolate is MK-7; the major fatty acids are summed feature 3 (C16:1ω7c/C16:1ω6c) (39.7%), iso-C15:0 (22.8%), iso-C17:0 3-OH (7.8%), and C16:0 (7.7%); and the major polar lipid is phosphatidylethanolamine. The phenotypic and chemotaxonomic data support the placement of strain 17JY9-4T within the genus Mucilaginibacter. However, the DNA-DNA relatedness between the isolate and M. rigui, M. lutimaris, M. phyllosphaerae, M. amnicola, and M. soli were 44.3 ± 3.0%, 38.6 ± 3.7%, 23.2 ± 2.9%, 21.9 ± 3.1%, and 18.6 ± 3.7%, respectively. The results of 16S rRNA gene sequence similarity analysis, DNA-DNA hybridization analysis, and the observed differentiating phenotypic properties from other closely related taxa clearly indicate that strain 17JY9-4T represents a novel species in the genus Mucilaginibacter, for which the name Mucilaginibacter terrigena sp. nov. is proposed. The type strain is 17JY9-4T (= KCTC 62294T = JCM 33049T).

Fusarium pathogenomics.

Fusarium is a genus of filamentous fungi that contains many agronomically important plant pathogens, mycotoxin producers, and opportunistic human pathogens. Comparative analyses have revealed that the Fusarium genome is compartmentalized into regions responsible for primary metabolism and reproduction (core genome), and pathogen virulence, host specialization, and possibly other functions (adaptive genome). Genes involved in virulence and host specialization are located on pathogenicity chromosomes within strains pathogenic to tomato (Fusarium oxysporum f. sp. lycopersici) and pea (Fusarium 'solani' f. sp. pisi). The experimental transfer of pathogenicity chromosomes from F. oxysporum f. sp. lycopersici into a nonpathogen transformed the latter into a tomato pathogen. Thus, horizontal transfer may explain the polyphyletic origins of host specificity within the genus. Additional genome-scale comparative and functional studies are needed to elucidate the evolution and diversity of pathogenicity mechanisms, which may help inform novel disease management strategies against fusarial pathogens.

Acinetobacter dijkshoorniae is a later heterotypic synonym of Acinetobacter lactucae.

Acinetobacter lactucae and Acinetobacter dijkshoorniae were recently described as novel species, and both were reported to be closely related to Acinetobacter pittii. Because they were reviewed and published almost concurrently, their descriptions did not include a specific comparison between these two novel species. Genomic data were provided in both initial descriptions, which simplifies the comparisons. Genome comparisons based on in silico DNA-DNA hybridizations, average nucleotide identity and core genome phylogeny of the type strain genomes establish that these strains are conspecific. Based on the rules of priority, A. dijkshoorniae should be reclassified as a later heterotypic synonym of A. lactucae.

Marinicella sediminis sp. nov., isolated from marine sediment.

A novel heterotrophic, Gram-stain-negative, aerobic, rod-shaped, pale yellow, non-motile and non-spore-forming bacterium, designated strain F2T, was isolated from marine sediment collected from the Weihai coast, Shandong Province, PR China. Optimal growth occurred at 33 °C (range, 10-37 °C), with 3.0-4.0 % (w/v) NaCl (1.0-8.0 %) and at pH 7.5-8.0 (pH 6.5-9.0). Q-8 was the sole respiratory quinone. The major polar lipids of strain F2T were phosphatidylmonomethylethanolamine, phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, two unidentified phospholipids and two unidentified polar lipids. The major cellular fatty acid in strain F2T was iso-C15 : 0. The genomic DNA G+C content of the strain was 48.1 mol%. Phylogenetic analysis based on 16S rRNA gene sequencing revealed that strain F2T is most closely related to Marinicella litoralis JCM 16154T (97.5 %) and Marinicella pacifica sw153T (96.0 %). Based on the results of our polyphasic analysis, we conclude that strain F2T represents a novel species of the genus Marinicella, for which the name Marinicella sediminis sp. nov. is proposed. The type strain of the new species is F2T (=KCTC 42953T=MCCC 1H00149T).

Proposed minimal standards for the use of genome data for the taxonomy of prokaryotes.

Advancement of DNA sequencing technology allows the routine use of genome sequences in the various fields of microbiology. The information held in genome sequences proved to provide objective and reliable means in the taxonomy of prokaryotes. Here, we describe the minimal standards for the quality of genome sequences and how they can be applied for taxonomic purposes.

Ovicidal and Larvicidal Effects of Garlic and Asafoetida Essential Oils Against West Nile Virus Vectors.

We examined the chemical composition of garlic and asafoetida essential oils and their individual and combined toxicity against larvae of Culex pipiens Linnaeus and Culex restuans Theobald (Diptera: Culicidae). The effect of the two essential oils on egg hatch was also examined. Ten and 12 compounds, respectively, were identified in garlic and asafoetida essential oils. Allyl disulfide (49.13%) and diallyl trisulfide (31.08%) were the most abundant compounds in garlic essential oil accounting for 80.2% of the total oil. In contrast, (E)-sec-butyl propenyl disulfide (30.03%), (Z)-sec-butyl propenyl disulfide (24.32%), and disulfide, methyl 1-(methylthio)propyl (21.87%) were the most abundant compounds in asafoetida essential oil. Allyl disulfide accounted for 7.38% of the total oil in asafoetida essential oil and was one of only three compounds found in both oils. For both mosquito species, garlic essential oil was more toxic than asafoetida essential oil with Cx. restuans (LC50: garlic = 2.7 ppm; asafoetida = 10.1 ppm) being more sensitive than Cx. pipiens (LC50: garlic = 7.5 ppm; asafoetida = 13.5 ppm). When combined, the two essential oils had antagonistic effects. The majority of Culex egg rafts exposed to garlic (73.1%) or asafoetida (55.8%) essential oils failed to hatch and larvae of the few that did hatch mostly died as first instars. Allyl disulfide exhibited strong ovicidal and larvicidal activity suggesting its important contribution to the overall toxicity of the two essential oils. Thus, garlic and asafoetida essential oils are potent mosquito ovicides and larvicides but if used jointly, they could undermine vector control programs.

Gracilimonas halophila sp. nov., isolated from a marine solar saltern.

A Gram-stain-negative and facultatively anaerobic bacterium, designated WDS2C40T, was isolated from a marine solar saltern in Weihai, China. Cells of strain WDS2C40T were 0.4-0.5 µm wide and 4.0-9.0 µm long, catalase-positive and oxidase-negative. Strain WDS2C40T was tolerant to moderate salt concentrations. Growth occurred at 20-42 °C (optimum, 37-40 °C), at pH 7.0-8.5 (optimum, 7.5-8.0) and with 2-16 % (w/v) NaCl (optimum, 6-8 %). A phylogenetic analysis of the 16S rRNA gene indicated that strain WDS2C40T was a member of the genus Gracilimonas within the family Balneolaceae. The most closely related neighbour was Gracilimonas rosea JCM 18898T (95.92 % similarity). The major respiratory quinone of strain WDS2C40T was menaquinone MK-7, and the dominant fatty acids were iso-C13 : 0, iso-C15 : 0 and summed feature 3. The major polar lipids were diphosphatidylglycerol, one kind of glycolipid and two unidentified phospholipids. The genomic DNA G+C content was 41.7 mol%. Based on this polyphasic taxonomic study, strain WDS2C40T is considered to represent a novel species in the genus Gracilimonas, for which the name Gracilimonas halophila sp. nov. is proposed. The type strain is WDS2C40T (=KCTC 52042T=MCCC 1H00135T).

Salibacter halophilus gen. nov., sp. nov., isolated from a saltern.

A Gram-stain-negative and facultatively anaerobic bacterium, JZ3C34T, was isolated from a saltern in Feicheng, China (36° 8' 24.45″ E 116° 49' 22.46″ N). Cells of strain JZ3C34T were 0.3-0.4 µm wide and 1.5-2.0 µm long, catalase-positive and oxidase-negative. Colonies on modified marine agar 2216 were orange, circular, convex, translucent and approximately 1 mm in diameter after incubation for 96 h at 33 °C. Growth occurred at 20-50 °C (optimally at 33 °C), at pH 6.5-8.5 (optimally at 7.0-8.0) and in the presence of 2-18 % (w/v) NaCl (optimally in 6 % NaCl). Phylogenetic analysis of the 16S rRNA gene indicated that strain JZ3C34T was a member of the family Cryomorphaceae within the order Flavobacteriales and the most closely related species was Owenweeksia hongkongensis DSM 17368T (89.2 % 16S rRNA gene sequence similarity). The major respiratory quinone of strain JZ3C34T was menaquinone MK-7, and the dominant fatty acids were iso-C15 : 0 and iso-C15 : 1 G. The major polar lipids were two unidentified lipids and phosphatidylethanolamine, and the genomic DNA G+C content was 39.6 mol%. Polyphasic taxonomy clearly places the new strain as a novel species within a new genus of the family Cryomorphaceae, for which the name Salibacter halophilus gen. nov., sp. nov. The type strain of Salibacter halophilus is JZ3C34T (=KCTC 52047T=MCCC 1K02288T).

Rhodohalobacter halophilus gen. nov., sp. nov., a moderately halophilic member of the family Balneolaceae.

A novel Gram-stain-negative, rod-shaped, facultatively anaerobic, oxidase-negative and catalase-positive bacterium, designated JZ3C29T, was isolated from a saltern located in Feicheng, PR China. JZ3C29T was tolerant of moderately saline conditions. Optimal growth occurred at 40 °C (range 20-50 °C) and pH 7.5-8.5 (range pH 7.0-9.0) with 8-10 % (w/v) NaCl (range 2-16 %). Phylogenetic analysis based on 16S rRNA gene sequences revealed that JZ3C29T shared highest similarity with Gracilimonas tropica CL-CB462T (90.5 %), Gracilimonas mengyeensis YIM J14T (90.5 %) and Gracilimonas rosea CL-KR2T (90.4 %) and less than 90.0 % similarity with other species of the phylum Bacteroidetes. The isolate formed a novel genus-level clade in the recently described family Balneolaceae. The polar lipid profile of the novel isolate consisted of diphosphatidylglycerol, phosphatidylethanolamine, three unidentified glycolipids, four unidentified phospholipids and two unidentified lipids. The dominant cellular fatty acids (>10 %) were summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH) and iso-C15 : 0 and the sole respiratory quinone was menaquinone 7 (MK-7). The DNA G+C content of JZ3C29T was 44.4 mol%. On the basis of these phenotypic and phylogenetic data, JZ3C29T should be classified as representing a novel genus and species within the family Balneolaceae, for which the name Rhodohalobacter halophilus gen. nov., sp. nov. is proposed. The type strain is JZ3C29T (=MCCC 1H00131T=KCTC 52046T=JCM 31413T).

Bacillus swezeyi sp. nov. and Bacillus haynesii sp. nov., isolated from desert soil.

Two isolates of Gram-reaction-positive, facultatively anaerobic, motile, rod-shaped, endospore-forming bacteria were identified during a survey of the diversity of strains belonging to the genus Bacillus deposited in the Agriculture Research Service Culture Collection. These strains were originally isolated from soil in Evolution Canyon III (Israel) in a survey of ecological diversification. Phylogenetic analysis of the 16S rRNA gene of strains NRRL B-41294T and NRRL B-41327T determined they were closely related to members of the Bacillus licheniformis clade. The genome of each strain was sequenced, and further analysis indicated that the strains represented unique species based on in silico DNA-DNA hybridization analyses. A phylogenomic analysis revealed that NRRL B-41294T and NRRL B-41327T were closely related to the group that includes B. licheniformis. In phenotypic characterization, both NRRL B-41294T and NRRL B-41327T were found to grow at temperatures of between 15 and 60 °C and tolerated up to 12 % NaCl (w/v). The predominant cellular fatty acids were anteiso-C15 : 0 and iso-C15 : 0, and peptidoglycan from cell walls contained meso-diaminopimelic acid. The DNA G+C content was 45.7 and 44.3 mol% for NRRL B-41327T and NRRL B-41294T, respectively. Furthermore, each strain had a unique carbon utilization pattern that distinguished it from its nearest phylogenetic neighbours. Based upon the consensus of phylogenetic and phenotypic analyses, we conclude that these strains represent two novel species within the genus Bacillus, for which the name Bacillus swezeyi sp. nov. is proposed, with type strain NRRL B-41294T (=CCUG 70177T), and the name Bacillus haynesii sp. nov. is proposed, with type strain NRRL B-41327T (=CCUG 70178T).

Chengkuizengella sediminis gen. nov. sp. nov., isolated from sediment.

A Gram-stain-positive, aerobic, motile, endospore-forming bacterium, designated strain J15A17T, was isolated from sediment of the South China Sea. The strain was oxidase-positive and catalase-negative. Optimal growth occurred at 33 °C, pH 7.5 and in the presence of 3 % (w/v) NaCl. On the basis of 16S rRNA gene sequence analysis, the strain showed closest similarity (92.8 %) to Paenibacillus puldeungensis strain CAU 9324T. Phylogenetic analysis based on 16S rRNA gene sequences showed that the isolate forms a separate branch within the family Paenibacillaceae, with the genus Cohnella as the most closely related genus. The DNA G+C content of strain J15A17T was 37.4 mol%. The strain contained MK-7 as the sole respiratory quinone; anteiso-C15 : 0 and iso-C16 : 0 were the major cellular fatty acids; and its polar lipid pattern consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, glycolipid and four unidentified phospholipids. The strain displayed the peptidoglycan type A4α l-Lys-d-Asp in the cell wall. Phylogenetic, physiological, biochemical and morphological differences between strain J15A17T and its closest relatives in the genera Cohnella, Fontibacillus and Paenibacillus suggest that strain J15A17T (=KCTC 33759T=MCCC 1H00137T) represents the type strain of a novel species in a new genus within the family Paenibacillaceae, Chengkuizengella sediminis gen. nov. sp. nov.

Colwellia agarivorans sp. nov., an agar-digesting marine bacterium isolated from coastal seawater.

A novel Gram-stain-negative, facultatively anaerobic, yellowish and agar-digesting marine bacterium, designated strain QM50T, was isolated from coastal seawater in an aquaculture site near Qingdao, China. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the isolate represented a member of the genus Colwellia and exhibited the highest sequence similarity (97.4 %) to Colwellia aestuarii SMK-10T. Average nucleotide identity (ANI) values based on draft genome sequences between strain QM50T and C. aestuarii KCTC 12480T showed a relatedness of 72.0 % (ANIb) and 85.1 % (ANIm). Cells of strain QM50T were approximately 0.3-0.6×0.8-2.5 µm in size and motile by means of a polar flagellum. Growth occurred in the presence of 1.0-6.0 % (w/v) NaCl (optimum, 2.0-3.0 %), at pH 6.5-8.5 (optimum, pH 7.0) and at 4-37 °C (optimum, 28-30 °C). Strain QM50T was found to contain ubiquinone 8 (Q-8) as the predominant ubiquinone and summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH), C16 : 0 and C17 : 1ω8c as the main cellular fatty acids. Phosphatidylethanolamine and phosphatidylglycerol were found to be major polar lipids. The DNA G+C content of strain QM50T was determined to be 35.7 mol%. On the basis of phylogenetic and phenotypic data, strain QM50T represents a novel species of the genus Colwellia, for which the name Colwellia agarivorans sp. nov. is proposed. The type strain is QM50T (=KCTC 52273T=MCCC 1H00143T).

Paraliobacillus sediminis sp. nov., isolated from East China sea sediment.

A Gram-strain-positive, facultatively anaerobic, motile, endospore-forming, slightly halophilic bacterium, designated strain 126C4T, was isolated from sediment from the East China Sea. The strain was catalase-positive and oxidase-negative. Optimal growth occurred at 28-30 °C, pH 7.0-7.5 and in the presence of 3-5 % (w/v) NaCl. Phylogenetic analyses, based on 16S rRNA gene sequence comparisons, showed that strain 126C4T was a member of the genus Paraliobacillus, with 16S rRNA gene sequence similarities to Paraliobacillus quinghaiensis YIM-C158T and Paraliobacillus ryukyuensis O15-7T of 96.2 % and 95.3 %, repectively. The DNA G+C content was 39.6 mol%. The strain contained MK-7 as the sole respiratory quinone, anteiso-C15 : 0, C16 : 0, iso-C15 : 0 and iso-C16 : 0 as the major cellular fatty acids, and its polar lipid pattern comprised diphosphatidylglycerol, phosphatidylethanolamine, three glycolipids and four unknown phospholipids. On the basis of its phylogenetic position, phenotypic traits and chemotaxonomic characteristics, it is suggested that strain 126C4T represents a novel species of the genus Paraliobacillus, for which the name Paraliobacillus sediminis sp. nov. is proposed. The type strain is 126C4T (=KCTC 33762T=MCCC 1H00136T).

Characterization of Tolypocladium cylindrosporum (Hypocreales: Ophiocordycipitaceae) and Its Impact Against Aedes aegypti and Aedes albopictus Eggs at Low Temperature.

We examined the growth characteristics of Tolypocladium cylindrosporum IBT 41712 and its potential to infect eggs of Aedes aegypti and Ae. albopictus at a low temperature (15°C). When grown on Sabouraud dextrose agar supplemented with yeast extract, the IBT 41712 formed white colonies turning to a slightly darker, off-white color when mature. The mycelia bore swollen conidiophores producing smooth-walled, oblong to cylindrical conidia with varying sizes, ranging from 1.5 to 3.5 µm long. To determine the optimum temperature for the fungus, we cultured the fungus at eight temperatures (4°C, 12°C, 15°C, 21°C, 28°C, 33°C, 37°C, and 40°C) and measured the diametric growth. The optimum temperature for growth was 28°C since it had the highest diametric growth rate (2.1 ± 0.05 mm/day) and the fastest sporulation period (within 8-10 days of incubation). There was no fungal growth at the 3 highest temperatures (33°C, 37°C, and 40°C) but plates incubated at 33°C, when shifted to optimal temperature (28°C), showed visible growth indicating that following incubation at 33°C, the fungus remained viable. The IBT 41712 successfully infected mosquito eggs at 15°C. Fungal treatment induced egg hatch on moist seed-germination paper and this effect was more pronounced in Ae. aegypti compared to Ae. albopictus. When treated eggs were immersed in dH2O 21 days posttreatment, larval hatch of both Ae. aegypti (control = 91%, 1 × 107 conidia/ml, fungal treatment = 0%) and Ae. albopictus (control = 85%, fungal treatment = 28%) was significantly lower in fungal treatment compared to the controls. The ability of the strain to grow in a wide temperature range, and effectively infect mosquito eggs and induce egg hatch at a low temperature warrants further investigation for its potential as a mosquito control agent targeting eggs that overwinter or undergo long diapause.

Midgut fungal and bacterial microbiota of Aedes triseriatus and Aedes japonicus shift in response to La Crosse virus infection.

Understanding how midgut microbial communities of field-collected mosquitoes interact with pathogens is critical for controlling vector infection and disease. We used 16S rRNA and internal transcribed spacer sequencing to characterize the midgut bacterial and fungal communities of adult females of Aedes triseriatus and Aedes japonicus collected as pupae in tree holes, plastic bins and waste tires and their response to La Crosse virus (LACV) infection. For both mosquito species and across all habitat and virus treatments, a total of 62 bacterial operational taxonomic units (OTUs) from six phyla and 21 fungal OTUs from two phyla were identified. The majority of bacterial (92%) and fungal (71%) OTUs were shared between the mosquito species; however, several OTUs were unique to each species. Bacterial and fungal communities of individuals that took either infectious or noninfectious bloodmeals were less diverse and more homogeneous compared to those of newly emerged adults. Interestingly, LACV-infected A. triseriatus and A. japonicus had higher bacterial richness and lower fungal richness compared to individuals that took a noninfectious bloodmeal, suggesting that viral infection was associated with an increase in bacterial OTUs and a decrease in fungal OTUs. For both mosquito species, several OTUs were identified that had both high fidelity and specificity to mosquito midguts that were infected with LACV. Overall, these findings demonstrate that bacterial and fungal communities that reside in mosquito midguts respond to host diet and viral infection and could play a role in modulating vector susceptibility to LACV.

Acinetobacter lactucae sp. nov., isolated from iceberg lettuce (Asteraceae: Lactuca sativa).

Strain NRRL B-41902T and three closely related strains were isolated from iceberg lettuce. The strain was found to consist of strictly aerobic, Gram-stain-negative rods that formed cocci in late stationary phase. 16S rRNA gene sequence analysis showed that strain NRRL B-41902T was most closely related to species within the genera Acinetobacter, and that a grouping of it and the three other closely related strains was most closely related to the type strain of Acinetobacter pittii, which was also confirmed through a phylogenomic analysis. Moreover, in silico DNA-DNA hybridization analysis revealed a substantial amount of genomic divergence (39.1 %) between strain NRRL B-41902T and the type strain of A. pittii, which is expected if the strains represent distinct species. Further phenotypic analysis revealed that strain NRRL B-41902T was able to utilize a combination of l-serine, citraconic acid and citramalic acid, which differentiated it from other, closely related Acinetobacter species. Therefore, strain NRRL B-41902T (=CCUG 68785T) is proposed as the type strain of a novel species, Acinetobacter lactucae sp. nov.

Genome analysis shows Bacillus axarquiensis is not a later heterotypic synonym of Bacillus mojavensis; reclassification of Bacillus malacitensis and Brevibacterium halotolerans as heterotypic synonyms of Bacillus axarquiensis.

Bacillus axarquiensis and Bacillus malacitensis were previously reported to be later heterotypic synonyms of Bacillus mojavensis, based primarily on DNA-DNA relatedness values. We have sequenced draft genomes of Bacillus axarquiensis NRRL B-41617T and Bacillus malacitensis NRRL B-41618T. Comparative genomics and DNA-DNA relatedness calculations showed that while Bacillus axarquiensis and Bacillus malacitensis are synonymous with each other, they are not synonymous with Bacillus mojavensis. In addition, a draft genome was completed for Brevibacterium halotolerans, a strain long suspected of being a Bacillus subtilis group member based on 16S rRNA similarities (99.8 % with Bacillus mojavensis). Comparative genomics and DNA-DNA relatedness calculations showed that Brevibacterium halotolerans is synonymous with Bacillus axarquiensis and Bacillus malacitensis. The pairwise in silico DNA-DNA hybridization values calculated in comparisons between the three conspecific strains were all greater than 92 %, which is well above the standard species threshold of 70 %. While the pairwise in silico DNA-DNA hybridization values calculated in comparisons of the three conspecific strains with Bacillus mojavensis were all less than 65 %. The combined results of our genotype and phenotype studies showed that Bacillus axarquiensis, Bacillus malacitensis and Brevibacterium halotolerans are conspecific and distinct from Bacillus mojavensis. Because the valid publication of the name Bacillus axarquiensis predates the publication of the name Bacillus malacitensis, we propose that Bacillus malacitensis be reclassified as a synonym of Bacillus axarquiensis. In addition, we propose to reclassify Brevibacterium halotolerans as a synonym of Bacillus axarquiensis. An amended description of Bacillus axarquiensis is provided.