Permuted tRNA genes of Cyanidioschyzon merolae, the origin of the tRNA molecule and the root of the Eukarya domain

Microorganisms serve as attractive resources, owing to their ability to synthesize structurally-diverse substanceswith various bioactivities. Within the Bacteria domain, members of the genus Streptomyces have demonstrated remarkableability to produce clinically useful, secondary metabolites such as anticancer, antioxidants, antivirals and antibacterials.Streptomyces pluripotens MUSC 135T was isolated as novel strain from mangrove forest in Malaysia. This strain exhibitedbroad spectrum bacteriocin against several pathogens including methicillin-resistant Staphylococcus aureus (MRSA) strainATCC BAA-44, Salmonella typhi ATCC 19430T and Aeromonas hydrophila ATCC 7966T. Thus, the strain was selected forwhole genome sequencing as an attempt to explore its bioactive potential. Here we report the first complete genome of S.pluripotens MUSC 135T genome which comprise of 7.35 Mbp with G+C content of 69.9 %. A total of 6,404 open readingframes (ORFs) were predicted, along with 18 rRNA and 69 tRNA genes. Using bacteriocin mining tool, BAGEL detectedeights gene clusters associated with bacteriocin production including lanthipeptides and linear azol(in)e-containing peptides(LAPs). Members of Streptomyces have contributed greatly towards improving lives, particularly against deadly infectionsand chronic diseases. The availability of S. pluripotens MUSC 135T genome sequence has opened new window for drugdiscovery, particularly for effective drugs against harmful pathogens such as MRSA and certainly deserves further detailedstudy.

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Mitochondrial genome evolution in pelagophyte algae

Genome Biology and Evolution ◽

10.1093/gbe/evab018 ◽

2021 ◽

Author(s):

Shannon J Sibbald ◽

Maggie Lawton ◽

John M Archibald

Keyword(s):

Mitochondrial Genome ◽

Harmful Algal Blooms ◽

Algal Blooms ◽

23S Rrna ◽

Mitochondrial Genomes ◽

Trna Genes ◽

Unique Region ◽

Long Read ◽

Genomic Studies ◽

Aureoumbra Lagunensis

Abstract The Pelagophyceae are marine stramenopile algae that include Aureoumbra lagunensis and Aureococcus anophagefferens, two microbial species notorious for causing harmful algal blooms. Despite their ecological significance, relatively few genomic studies of pelagophytes have been carried out. To improve understanding of the biology and evolution of pelagophyte algae, we sequenced complete mitochondrial genomes for A. lagunensis (CCMP1510), Pelagomonas calceolata (CCMP1756) and five strains of A. anophagefferens (CCMP1707, CCMP1708, CCMP1850, CCMP1984 and CCMP3368) using Nanopore long-read sequencing. All pelagophyte mitochondrial genomes assembled into single, circular mapping contigs between 39,376 base-pairs (bp) (P. calceolata) and 55,968 bp (A. lagunensis) in size. Mitochondrial genomes for the five A. anophagefferens strains varied slightly in length (42,401 bp—42,621 bp) and were 99.4%-100.0% identical. Gene content and order was highly conserved between the A. anophagefferens and P. calceolata genomes, with the only major difference being a unique region in A. anophagefferens containing DNA adenine and cytosine methyltransferase (dam/dcm) genes that appear to be the product of lateral gene transfer from a prokaryotic or viral donor. While the A. lagunensis mitochondrial genome shares seven distinct syntenic blocks with the other pelagophyte genomes, it has a tandem repeat expansion comprising ∼40% of its length, and lacks identifiable rps19 and glycine tRNA genes. Laterally acquired self-splicing introns were also found in the 23S rRNA (rnl) gene of P. calceolata and the coxI gene of the five A. anophagefferens genomes. Overall, these data provide baseline knowledge about the genetic diversity of bloom-forming pelagophytes relative to non-bloom-forming species.

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The Chloroplast Phylogenomics and Systematics of Zoysia (Poaceae)

Plants ◽

10.3390/plants10081517 ◽

2021 ◽

Vol 10 (8) ◽

pp. 1517

Author(s):

Se-Hwan Cheon ◽

Min-Ah Woo ◽

Sangjin Jo ◽

Young-Kee Kim ◽

Ki-Joong Kim

Keyword(s):

Northeast Asia ◽

Single Copy ◽

Rrna Genes ◽

Bootstrap Support ◽

Trna Genes ◽

Protein Coding ◽

Tropical Regions ◽

Relationship Of ◽

The Relationship ◽

Simple Sequence

The genus Zoysia Willd. (Chloridoideae) is widely distributed from the temperate regions of Northeast Asia—including China, Japan, and Korea—to the tropical regions of Southeast Asia. Among these, four species—Zoysia japonica Steud., Zoysia sinica Hance, Zoysia tenuifolia Thiele, and Zoysia macrostachya Franch. & Sav.—are naturally distributed in the Korean Peninsula. In this study, we report the complete plastome sequences of these Korean Zoysia species (NCBI acc. nos. MF953592, MF967579~MF967581). The length of Zoysia plastomes ranges from 135,854 to 135,904 bp, and the plastomes have a typical quadripartite structure, which consists of a pair of inverted repeat regions (20,962~20,966 bp) separated by a large (81,348~81,392 bp) and a small (12,582~12,586 bp) single-copy region. In terms of gene order and structure, Zoysia plastomes are similar to the typical plastomes of Poaceae. The plastomes encode 110 genes, of which 76 are protein-coding genes, 30 are tRNA genes, and four are rRNA genes. Fourteen genes contain single introns and one gene has two introns. Three evolutionary hotspot spacer regions—atpB~rbcL, rps16~rps3, and rpl32~trnL-UAG—were recognized among six analyzed Zoysia species. The high divergences in the atpB~rbcL spacer and rpl16~rpl3 region are primarily due to the differences in base substitutions and indels. In contrast, the high divergence between rpl32~trnL-UAG spacers is due to a small inversion with a pair of 22 bp stem and an 11 bp loop. Simple sequence repeats (SSRs) were identified in 59 different locations in Z. japonica, 63 in Z. sinica, 62 in Z. macrostachya, and 63 in Z. tenuifolia plastomes. Phylogenetic analysis showed that the Zoysia (Zoysiinae) forms a monophyletic group, which is sister to Sporobolus (Sporobolinae), with 100% bootstrap support. Within the Zoysia clade, the relationship of (Z. sinica, Z japonica), (Z. tenuifolia, Z. matrella), (Z. macrostachya, Z. macrantha) was suggested.

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