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A novel halotolerant actinobacterium, designated as RG38T, capable of producing black extracellular melanin pigment on SP2 agar, was isolated from the roots of Tagetes patula. Comparative analysis of the 16S rRNA gene sequence revealed the highest similarity to Streptomyces collinus NBRC 12759T (99.3%). Phylogenetic analysis showed that strain RG38T clustered within the genus Streptomyces forming a monophyletic cluster with its close relatives. The average nucleotide identity (ANI), digital DNA-- DNA hybridization (dDDH), and amino-acid identity (AAI) values between strain RG38T and related species within the genus Streptomyces were below the standard threshold for prokaryotic species delineation. The DNA G + C content of the strain RG38T was determined to be 73.3%. The genome size measured 7,150,598 bp comprising 17 contigs and encompassed 6,053 protein coding genes. AntiSMASH analysis of the whole genome revealed 35 putative biosynthetic gene clusters (BGCs) responsible for various secondary metabolites. Among these clusters, two gene clusters exhibited 100% similarity to the chromomycin A3, albaflavenone, and anthracimycin, respectively. These compounds were reported to possess significant anticancer and antibacterial activities. LC--MS-based analysis, coupled with further isolation studies, confirmed the production of chromomycins A2 (1), A3 (2), and their derivatives, along with their antibiotic activities. These findings underscore the potential of this novel strain as a novel resource for the discovery of diverse antimicrobial compounds. This study is the first to report an antimicrobial compound producing Streptomyces species isolated from medicinal plant T. patula. Based on a polyphasic study, the strain RG38T isolated from an unexplored habitat with a high potential for new natural products represents a novel species within the genus Streptomyces. Accordingly, we propose the name Streptomyces tagetis sp. nov. for this novel species, with the type strain is RG38T (=KCTC 49624T = BRC 15113T). [ABSTRACT FROM AUTHOR]

A novel halotolerant actinobacterium, designated as RG38T, capable of producing black extracellular melanin pigment on SP2 agar, was isolated from the roots of Tagetes patula. Comparative analysis of the 16S rRNA gene sequence revealed the highest similarity to Streptomyces collinus NBRC 12759T (99.3%). Phylogenetic analysis showed that strain RG38T clustered within the genus Streptomyces forming a monophyletic cluster with its close relatives. The average nucleotide identity (ANI), digital DNA–DNA hybridization (dDDH), and amino-acid identity (AAI) values between strain RG38T and related species within the genus Streptomyces were below the standard threshold for prokaryotic species delineation. The DNA G + C content of the strain RG38T was determined to be 73.3%. The genome size measured 7,150,598 bp comprising 17 contigs and encompassed 6,053 protein coding genes. AntiSMASH analysis of the whole genome revealed 35 putative biosynthetic gene clusters (BGCs) responsible for various secondary metabolites. Among these clusters, two gene clusters exhibited 100% similarity to the chromomycin A3, albaflavenone, and anthracimycin, respectively. These compounds were reported to possess significant anticancer and antibacterial activities. LC–MS-based analysis, coupled with further isolation studies, confirmed the production of chromomycins A2 (1), A3 (2), and their derivatives, along with their antibiotic activities. These findings underscore the potential of this novel strain as a novel resource for the discovery of diverse antimicrobial compounds. This study is the first to report an antimicrobial compound producing Streptomyces species isolated from medicinal plant T. patula. Based on a polyphasic study, the strain RG38T isolated from an unexplored habitat with a high potential for new natural products represents a novel species within the genus Streptomyces. Accordingly, we propose the name Streptomyces tagetis sp. nov. for this novel species, with the type strain is RG38T (=KCTC 49624T = TBRC 15113T).

“Thirukkural” from Tamil language gives good and right directions for walks life. It discusses the positive and negative results of various actions of men in all areas of life. The ideas of “Thirukkural” have been accepted everywhere in the world for they are common one for the entire human race. “Thirukkural” is written in couplets and in each of them a particular message about an aspect of life begins and ends. The meaning of the couplets have been analyzed and explained in detailed ways by many Tamil veteran scholars. The important point of this article is that the idea of every couplet implies the divine source of source which is the center of that idea. This fact about the couplets in “Thirukkural” becomes an example for Derrida‟s concept of center which can be anywhere in the text or even somewhere out of text in his „Structure, Sign, and Play”.

The urgent need for novel antibiotics in the face of escalating global antimicrobial resistance necessitates innovative approaches to identify bioactive compounds. Actinomycetes, renowned for their prolific production of antimicrobial agents, stand as a cornerstone in this pursuit. Their diverse metabolites exhibit multifaceted bioactivities, including potent antituberculosis, anticancer, immunomodulatory, immuno-protective, antidiabetic, etc. Though terrestrial sources have been exploited significantly, contemporary developments in the field of antimicrobial drug discovery have put marine actinomycetes in a prominent light as a promising and relatively unexplored source of novel bioactive molecules. This is further boosted by post-genomic era advances like bioinformatics-based secretome analysis and reverse engineering that have totally revitalized actinomycetes antibiotic research. This review highlights actinomycetes-based chemically diverse scaffolds and clinically validated antibiotics along with the enduring significance of actinomycetes from untouched ecosystems, especially with recent advanced techniques in the quest for next-generation antimicrobials., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

• New N -methyl cyclic pentapeptide and alternariol glucoside. • Marine-facultative fungi from an unexplored area of Mexico. • Absolute configuration by spectrometric analysis and chemical degradation. • Cytotoxic, antimicrobial and phytogrowth inhibition activities. During our ongoing research on fungal strains from unexplored sources, the reinvestigation of the CHCl 3 −MeOH extract of the marine-facultative Aspergillus sp. MEXU 27854 yielded a new N -methyl cyclic pentapeptide (1) along with known butyrolactone II and PF1233 A. In addition, from the marine-facultative Gymnoascus hyalinosporus MEXU 29901, a new alternariol glucoside, 10 -O -[ β - d -(4-methoxyl-glucopyranosyl)]-4- O -methylalternariol (2) and known alternariol 4- O- methyl ether, alternariol and beauvericin, were isolated. The structures of 1 and 2 were established by detailed spectroscopic data, and their absolute configuration was ascertained by Marfey's analysis and HRESIMS-MS/MS data for 1 , and by chemical degradation and optical rotation analysis for 2. [ABSTRACT FROM AUTHOR]

The biodiversity of the 5,000 km-long Great Escarpment of southern Africa is currently poorly known, despite hosting half of the subcontinent's centres of plant endemism and to have a rich endemic vertebrate fauna, particularly in the north-west and east. A country-based overview of endemism, data deficiencies and conservation challenges is provided, with Angola being the country in most need of Escarpment research and conservation. Given that the Escarpment provides most of the subcontinent's fresh water, protection and restoration of Escarpment habitat providing such ecological services is urgently required. Key research needs are exhaustive biodiversity surveys, systematic studies to test refugia and migration hypotheses, and the effects of modern climate change. Such research results can then be consolidated into effective conservation planning and co-ordinated international efforts to protect the rich biodiversity of the Escarpment and the ecological services it provides. [ABSTRACT FROM AUTHOR]

For all of the prodigious output on the subject of al-Qaeda from scholars and policy-makers alike recently, a number of consequential assumptions about the group remain startlingly unexplored. This paper examines six such assumptions, revealing each one's foundational role in assertions and debates about al-Qaeda (and, in most cases, about terrorism more broadly) despite the relatively unexplored status of each. These six assumptions relate to: (1) the link between the causes or roots of al-Qaeda's violence and deep-rooted anti-Americanism; (2) the relationship between fighting 'Al-Qaeda in Iraq' and fighting al-Qaeda globally; (3) the effect of eliminating individual terrorists; (4) the strategic versus social sources of terrorists' motivation; (5) the demonstrative effects of increased homeland security; and (6) the role of the internet in actual terrorist activity. [ABSTRACT FROM AUTHOR]