The Dean's award for excellent research results presented in the dissertation thesis

We are pleased to announce that on 25 June 2025, our PhD student Shun-Min Yang received the Dean's award for excellent research results presented in the dissertation thesis entitled Heme biosynthesis in diatoms, in the study programme of Integrative Biology.

This dissertation focused on the subcellular localisation of heme biosynthetic enzymes in the diatom Phaeodactylum tricornutum. Due to the complex evolutionary history of secondary endosymbiosis, these organisms possess multiple paralogous genes of distinct origins, a phenomenon known as pseudoparalogy. The thesis provided a comprehensive analysis of the localisation of all heme pathway enzymes, including the pseudoparalogous forms of uroporphyrinogen decarboxylase (UROD) and coproporphyrinogen III oxidase (CPOX), and examined their differential responses to various environmental stimuli. One chapter also explored putative mitochondrial histones in Chromera velia, the closest photosynthetic relative of apicomplexan parasites, discussing their evolutionary distribution and potential function.

We warmly congratulate Shun-Min on this prestigious recognition and wish him continued success in his scientific career.

Disertation thesis:Shun-Min YANG - Heme biosynthesis in diatoms

Abstract: This thesis focused on the localization of heme biosynthetic enzymes in diatoms. The evolution of complex endosymbiosis has led to the accumulation of multiple paralogous genes derived from different origins, known as pseudoparalogy. The thesis described the detailed localization of all heme pathway enzymes in diatom Phaeodactylum tricornutum, including those of pseudoparalogous enzymes, uroporphyrinogen decarboxylase (UROD) and coproporphyrinogen III oxidase (CPOX), and further revealed their differential responses to various environmental factors. In Chapter Four, putative mitochondrial histones were investigated in Chromera velia, the closest phototrophic relative of apicomplexan parasites, and their evolutionary distribution and possible functions were discussed

Keywords: chloroplast tetrapyrrole horizontal gene transfer algae organelle evolution endosymbiosis histone mitochondrion apicomplexan

Supervisor: prof. Ing. Miroslav Oborník, Ph.D.

Photo credits: Vijaya Geetha Gonepogu and Dorsaf Ennaceur.