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Phylogenetic analyses based on 16S rRNA gene sequences of members of the family Staphylococcaceae showed the presence of para- and polyphyletic genera. This finding prompted a thorough investigation into the taxonomy of the Staphylococcaceae family by analysing their core genome phylogeny complemented with genome-based indices such as digital DNA–DNA hybridization, average nucleotide identity and average amino acid identity. The resulting data suggested the following proposals: Auricoccus indicus was reduced in taxonomic rank as a later heterotypic synonym of Abyssicoccus albus ; Staphylococcus petrasii subsp. jettensis as a later heterotypic synonym of Staphylococcus petrasii subsp. petrasii ; the unification of Staphylococcus aureus subsp. anaerobius and Staphylococcus aureus subsp. aureus as Staphylococcus aureus ; the unification of Staphylococcus carnosus subsp. utilis and Staphylococcus carnosus subsp. carnosus as Staphylococcus carnosus ; the unification of Staphylococcus saprophyticus subsp. bovis and Staphylococcus saprophyticus subsp. saprophyticus as Staphylococcus saprophyticus ; Staphylococcus succinis subsp. casei as the novel species Staphylococcus casei; Staphylococcus schleiferi subsp. coagulans as the novel species Staphylococcus coagulans; Staphylococcus petrasii subsp. croceilyticus as the novel species Staphylococcus croceilyticus; Staphylococcus petrasii subsp. pragensis as the novel species Staphylococcus pragensis; Staphylococcus cohnii subsp. urealyticus as the novel species Staphylococcus urealyticus; the reassignment of Staphylococcus sciuri , Staphylococcus fleurettii , Staphylococcus lentus , Staphylococcus stepanovicii and Staphylococcus vitulinus to the novel genus Mammaliicoccus with Mammaliicoccus sciuri as the type species; and the formal assignment of Nosocomiicoccus as a member of the family Staphylococcaceae .

Zinc solubilizing ability of Bacillus sp. and Pseudomonas sp. was assessed using zinc oxide, zinc sulphide (sphalerite) and zinc carbonate in both plate and broth assays. ZSB-O-1 (Bacillus sp.) showed highest dissolution in the zinc sulphide (Sphalerite ore), with 2.80 cm of dissolution zone and 14.50 cm 2 of area in the plate assay and 13.60 mg kg -1 of zinc in the broth assay on the 15 th day after inoculation. The ZSB-S-2 (Pseudomonas sp.) showed more solubilizing ability in the zinc oxide, with 3.30 cm clearing zone and 20.43 cm 2 area in the plate assay and 16.40 mg kg -1 of zinc in the broth assay over the same inoculation period. The isolate ZSB-S-4 (Pseudomonas sp.) has highest solubilizing potential in zinc carbonate with 6.20 cm of dissolution zone and 13.40 cm 2 area in the plate assay and 13.40 mg kg -1 of zinc in the broth assay. Thus, the solubilization potential varies among different cultures. The solubilization might be due to production of acids by the culture, since the pH of the culture broth has been shifted form 7.0-7.3 to 4.8-6.5 after 15 days of inoculation. The zinc tolerance limit for two cultures (ZSB-O-1 and ZSB-S-2) was studied and determined to be upto 100 mg kg -1 of zinc in the in vitro broth assay.

Aims:  To evaluate whether the gut bacteria of insecticide‐resistant, insecticide‐susceptible and field‐caught populations of the lepidopteran insect pest diamondback moth (DBM) –Plutella xylostella (L.) – are variable and their role in host protection and nutrition. Methods and Results:  The gut bacterial populations of the three DBM larvae populations were found to be significantly different, irrespective of the developmental stage. The 16S rRNA gene sequence analysis of the DBM gut bacteria revealed that the bacterial population from the prothiofos‐resistant larval gut was more diversified with Pseudomonas sp., Stenotrophomonas sp., Acinetobacter sp., and Serratia marcescens. Meanwhile, the susceptible larvae were associated with Brachybacterium sp., Acinetobacter sp. and S. marcescens and the field‐caught population harboured a rather simple gut microflora of phylotypes belonging to Serratia. The siderophore‐producing Pseudomonas sp. strain PRGB06 showed antagonistic activity towards entomopathogenic fungi, including Beaveria bassiana, Hirsutella thompsonii, Metarhizium anisopliae, Paecilomyces sp., and Paecilomyces tenuipes, while the chitinase‐producing S. marcescens enhanced the larval growth and development. Conclusion:  There was a significant variation in the gut bacteria from the three different populations of DBM. The production of antifungal siderophore compounds, like pyoverdine, may contribute to host antagonism against entomopathogens. The production of chitinase by gut bacteria appeared to contribute to host nutrition. Significance and Impact of the Study:  The results provide the first comprehensive description of the gut microbial communities in three different populations of an important crucifer pest DBM and suggest that the bacteria associated with the insect pest could be of interest for developing a pest management strategy.

Gluconacetobacter diazotrophicus has a long-standing history of bacterial-plant interrelationship as a symbiotic endophyte capable of fixing atmospheric nitrogen. In low nitrogen fertilized sugarcane fields it plays a significant role and its occurrence was realised in most of the sugarcane growing countries. In this mini review, the association of G. diazotrophicus with sugarcane, other crop plants and with various hosts is discussed. The factors affecting survival in the rhizosphere and the putative soil mode of transmission are emphasized. In addition, other N(2)-fixing Acetobacteraceae members, including Gluconacetobacter azotocaptans, Gluconacetobacter johannae and Swaminathania salitolerans, occurring in coffee, corn and rice plants are also covered. Lastly, the plant-growth-promoting traits identified in this group of bacteria, including N(2) fixation, phytohormone synthesis, P and Zn solubilization and biocontrol, are analysed.

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Endophytic bacteria were isolated from the tissues of surface sterilized roots, stems, and leaves of fifty different crop plants. Phenotypic, biochemical tests and species-specific PCR assay permitted identification of four isolates of Gluconacetobacter diazotrophicus from root tissues of carrot (Daucus carota L.), raddish (Raphanus sativus L.), beetroot (Beta vulgaris L.) and coffee (Coffea arabica L.). Further the plant growth promoting traits such as nitrogenase activity, production of phytohormone indole acetic acid (IAA), phosphorus and zinc solubilization were assessed. Significant nitrogenase activity was recorded among the isolates and all the isolates produced IAA in the presence of tryptophan. Though all the four isolates efficiently solubilized phosphorus, the zinc solubilizing ability differed among the isolates.

A methylotrophic nitrogen-fixing bacterial strain, Ah-143 T , isolated from the rhizosphere soil of field-grown groundnut was analysed by a polyphasic taxonomic approach. Comparative 16S rRNA gene sequence analysis combined with rpoB gene sequence analysis allocated strain Ah-143 T to the family Enterobacteriaceae, with Enterobacter radicincitans and Enterobacter cowanii as the closest relatives. The strain is Gram-stain-negative, non-spore-forming, aerobic and motile, having straight rod-shaped cells with a DNA G+C content of approximately 53.2 mol%. The strain utilizes methanol as a carbon source and the mxaF gene was closely related to the mxaF gene of members of the genus Methylobacterium. The fatty acid profile consisted of C 16 : 0 , C 17 : 0 cyclo, C 18 : 1 v7c, summed feature 2 (iso-C 16 : 1 I and/or C 14 : 0 3-OH) and summed feature 3 (iso-C 15 : 0 2-OH and/or C 16 : 1 v7c) as the major components. DNA-DNA relatedness of strain Ah-143 T with its close relatives was less than 20 %. On the basis of the phylogenetic analyses, DNA-DNA hybridization data, and unique physiological and biochemical characteristics, it is proposed that the strain represents a novel species of the genus Enterobacter and should be named Enterobacter arachidis sp. nov. The type strain is Ah-143 T (5NCIMB 14469 T 5KCTC 22375 T ).The genus Enterobacter is clearly separated from other groups, forming a distinct branch, and at the time of writing included 22 species with validly published names (http://www.bacterio.cict.fr/e/enterobacter.html), Enterobacter cloacae being the type species (Hormaeche & Edwards, 1960). Members of the genus Enterobacter are detected in various environments, such as infant formula (Stephan et al., 2007(Stephan et al., , 2008, clinical specimens (Brenner et al., 1986;Hoffmann et al., 2005) and in association with plants (Egamberdieva et al., 2008; Kämpfer et al., 2005). Several species of the genus Enterobacter are known to interact and exert beneficial effects on plant growth. The plant-growthpromoting effects of beneficial bacteria may occur through direct or indirect mechanisms that include production of phytohormones or enzymes that promote plant growth, increased nutrient uptake, and prevention of deleterious phytopathogens (Glick et al., 1999;Whipps, 2001). The complex mixture of carbohydrates, amino acids, organic acids and other nutrients released from seeds and roots are thought to support the growth of beneficial bacteria such as E. cloacae in the spermosphere and rhizosphere. E. cloacae colonizes the spermospheres and rhizospheres of a number Abbreviation: ACCD, 1-aminocyclopropane-1-carboxylate deaminase.The GenBank/EMBL/DDBJ accession numbers for the 16S rRNA, rpoB, nifH and mxaF gene sequences of strain Ah-143 T are EU672801, FJ768683, FJ460712 and EU912491, respectively.Phase-contrast and scanning electron micrographs of cells of strain Ah-143 T , phylogenetic trees based on rpoB and nifH gene sequences, and cellular fatty acid compositions of strain Ah-143 T and related species of the genus...