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Biology subjects

Ebenezer, T. E.

Publications and source records attributed to Ebenezer, T. E..

2 recordsLinked to original sources

Chromosome-level genome assembly of Helichrysum odoratissimum, a medicinal plant from Southern Africa

Helichrysum odoratissimum, a plant species native to Southern Africa, holds deep cultural significance and is widely used in traditional medicine. It is valued for its antimicrobial and anti-inflammatory properties and is cultivated and traded in South Africa due to its growing commercial relevance to the pharmaceutical and cosmetic industries. Despite its ecological and economic importance, genomic resources for this species remain limited. Here, we report a high-quality chromosome-level genome assembly for H. odoratissimum to facilitate investigations into its genetic basis of bioactivity, environmental adaptation, and taxonomic relationships. High-molecular-weight DNA extracted from leaf tissue was sequenced using Oxford Nanopore Technologies (ONT) long-read sequencing, and Hi-C proximity ligation data were generated to enable chromosome-scale scaffolding. The final assembly spans 2.4 Gb, with a scaffold N50 of 354 Mb, and was anchored and oriented into seven chromosomes, with 2,935 smaller scaffolds remaining unplaced. Assembly quality and completeness were evaluated using QUAST and BUSCO, and chromosomal structure was validated using Hi-C contact maps. This genome provides a foundational resource for functional genomics, conservation planning, molecular breeding, and the discovery of bioactive compounds underpinning the medicinal and commercial value of H. odoratissimum.

genomics↗

Proteome of the secondary plastid of Euglena gracilis reveals metabolic quirks and colourful history

Euglena gracilis is a well-studied biotechnologically exploitable phototrophic flagellate harbouring secondary green plastids. Here we describe its plastid proteome obtained by high-resolution proteomics. We identified 1,345 candidate plastid proteins and assigned functional annotations to 774 of them. More than 120 proteins are affiliated neither to the host lineage nor the plastid ancestor and may represent horizontal acquisitions from various algal and prokaryotic groups. Reconstruction of plastid metabolism confirms both the presence of previously studied/predicted enzymes/pathways and also provides direct evidence for unusual features of its metabolism including uncoupling of carotenoid and phytol metabolism, a limited role in amino acid metabolism and the presence of two sets of the SUF pathway for FeS cluster assembly. Most significantly, one of these was acquired by lateral gene transfer (LGT) from the chlamydiae. Plastidial paralogs of membrane trafficking-associated proteins likely mediating a poorly understood fusion of transport vesicles with the outermost plastid membrane were identified, as well as derlin-related proteins that potentially act as protein translocases of the middle membrane, supporting an extremely simplified TIC complex. The proposed innovations may be also linked to specific features of the transit peptide-like regions described here. Hence the Euglena plastid is demonstrated to be a product of several genomes and to combine novel and conserved metabolism and transport processes.

evolutionary biology↗