Bacillus aryabhattai AB211 is a plant growth promoting, Gram-positive firmicute, isolated from the rhizosphere of tea (Camellia sinensis), one of the oldest perennial crops and a major non-alcoholic beverage widely consumed all over the world. The whole genome of B. aryabhattai AB211 was sequenced, annotated and evaluated with special focus on genomic elements related to plant microbe interaction. It’s genome sequence reveals the presence of a 5,403,026 bp chromosome. A total of 5226 putative protein-coding sequences, 16 rRNA, 120 tRNA, 8 ncRNAs, 58 non-protein coding genes, and 11 prophage regions were identified. Genome sequence comparisons between strain AB211 and other related environmental strains of B. aryabhattai, identified about 3558 genes conserved among all B. aryabhattai genomes analyzed. Most of the common genes involved in plant growth promotion activities were found to be present within core genes of all the genomes used for comparison, illustrating possible common plant growth promoting traits shared among all the strains of B. aryabhattai. Besides the core genes, some genes were exclusively identified in the genome of strain AB211. Functional annotation of the genes predicted in the strain AB211 revealed the presence of genes responsible for mineral phosphate solubilization, siderophores, acetoin, butanediol, exopolysaccharides, flagella biosynthesis, surface attachment/biofilm formation, and indole acetic acid production, most of which were experimentally verified in the present study. Genome analysis and experimental evidence suggested that AB211 has robust central carbohydrate metabolism implying that this bacterium can efficiently utilize the root exudates and other organic materials as an energy source. Genes for the production of peroxidases, catalases, and superoxide dismutases, that confer resistance to oxidative stresses in plants were identified in AB211 genome. Besides these, genes for heat shock tolerance, cold shock tolerance, glycine-betaine production, and antibiotic/heavy metal resistance that enable bacteria to survive biotic/abiotic stress were also identified. Based on the genome sequence information and experimental evidence as presented in this study, strain AB211 appears to be metabolically diverse and exhibits tremendous potential as a plant growth promoting bacterium.

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Mangroves are among the most diverse and productive coastal ecosystems in the tropical and subtropical regions. Environmental conditions particular to this biome make mangroves hotspots for microbial diversity, and the resident microbial communities play essential roles in maintenance of the ecosystem. Recently, there has been increasing interest to understand the composition and contribution of microorganisms in mangroves. In the present study, we have analyzed the diversity and distribution of archaea in the tropical mangrove sediments of Sundarbans using 16S rRNA gene amplicon sequencing. The extraction of DNA from sediment samples and the direct application of 16S rRNA gene amplicon sequencing resulted in approximately 142 Mb of data from three distinct mangrove areas (Godkhali, Bonnie camp, and Dhulibhashani). The taxonomic analysis revealed the dominance of phyla Euryarchaeota and Thaumarchaeota (Marine Group I) within our dataset. The distribution of different archaeal taxa and respective statistical analysis (SIMPER, NMDS) revealed a clear community shift along the sampling stations. The sampling stations (Godkhali and Bonnie camp) with history of higher hydrocarbon/oil pollution showed different archaeal community pattern (dominated by haloarchaea) compared to station (Dhulibhashani) with nearly pristine environment (dominated by methanogens). It is indicated that sediment archaeal community patterns were influenced by environmental conditions.

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It has been recently demonstrated by Colonge and Pichat (1) that the aluminum chloride-catalyzed reaction between benzene and allylacetone leads to the formation of 2-phenylhexan-5-one in excellent yield. Similarly toluene reacts with allylacetone to give 2-p-tolylhexan-5-one. The proof of the structures of the products was obtained through hypobromite oxidation to the corresponding acids and through syntheses of naphthalene homologs from the Friedel-Crafts condensation products (2). Somewhat parallel observations were previously made by Brochet (3) who obtained a satisfactory yield of 2-phenylhexane by reacting benzene and 1-hexene in presence of sulphuric acid as the catalyst.It appears, therefore, that the +E ketonic group in allylacetone has no bearing on the course of the cationotropic reactions.An examination of the structures of the above products obtained by Colonge and Pichat (1) would suggest a possibility of a development of a convenient and elegant method for the synthesis of polynuclear aromatic and hydroaromatic systems. Following this idea the synthesis of 1,4-dimethylnaphthalene (2) was fully corroborated in this laboratory (4). This method was then extended to a synthesis of 1,4-dimethylphenanthrene with naphthalene as the starting material. Xaphthalene in carbon disulphide solution reacted smoothly with allylacetone in the presence of aluminum chloride to give 2-(/3-naphthyl)hexan-5-one. The formation of binaphthyl (6) which might arise due to the high reactivity of the aromatic substrate towards aluminum chloride was obviated by using a dilute solution of naphthalene in carbon disulphide. The product, 2-(/3-naphthyl)hexan-5-one (I), was reduced to the corresponding carbinol (11) through the Pondorff method. The sodium and moist ether method was avoided, as nuclear reduction by dissolving metals may well be induced in this case. Cyclization of the above alcohol with concentrated sulphuric acid ( 5 ) followed by dehydrogenation by palladium-charcoal (30%) (7) gave 1,4-dimethylphenanthrene (IV). Bardhan and Sengupta (8) claimed to have first synthesized 1,Cdimethylphenanthrene, but the structure of their synthetic product was invalidated by Bogert, et al. (9), who suggested that Bardhan and Sengupta's product should in all probability be 1,3-dirnethylphenanthrene. Later Bachmann and Edgerton (10) confirmed the physical data for 1,4-dimethylphenanthrene as recorded by Bogert, et al. (9). Our results fully agree with the observations of the American workers (9, 10, 11). 1 A preliminary report of this work appeared in Ezperientia, 7, 372 (1951).

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