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Bakteryjne strategie wykorzystania jonów metali – kulisy chemii koordynacyjnej

Piasta Karolina, Mular Andrzej, Rola Anna, Dzyhovskyi Valentyn, Potok Paulina, Orzeł Bartosz, Potocki Sławomir, Stokowa-Sołtys Kamila, Kozłowski Henryk, Gumienna-Kontecka Elżbieta

Wiadomości Chemiczne

2022

[Z] 76, 5-6

287-308

In the Biological Inorganic Chemistry Group we are inspired to better understand metal ions acquisition and homeostasis in pathogenic bacteria, and in this review we present three different approaches to the role of these processes. The growing importance of a full understanding of the iron transport system in pathogens prompted us to study synthetic analogs of siderophores, used as structural probes in the process of iron uptake by microorganisms. The ferrichrome biomimetic analogs allowed efficient Fe(III) chelation under biological conditions and were recognized better by P. putida. than E. coli, suggesting differences in uptake mechanisms. Addition of a fluorescent probe to the compound allowed to track biological fate of studied complexes [1, 2]. Biomimetics of ferrioxamine E revealed their potential as radioactive 68Ga(III)-based probes [3], and studies of Zr(IV) complexes permitted to explain the in vivo behavior of desferrioxamine B as 89Zr(IV) radionuclide carrier [4], as well as design better chelators for this metal ion [5]. One of the possible mammalian immune system responsesto mycobacterial infection is the increase of Zn(II) concentration in phagosomes to a toxic level [6-8]. The mycobacterial SmtB protein is a transcription regulator that in the presence of high concentrations of metals, dissociates from DNA and activates the expression of metal efflux proteins. We focused on α5 Zn(II) binding domains of SmtB/BigR4 proteins [9], looking at the coordination modes and thermodynamics of their Zn(II) and Ni(II) complexes. The study points out the specificity of metal-ligand interactions and the effect of mutations on the coordination properties of studied systems. The project can be considered as an introduction to the new strategies in tuberculosis treatment based on Zn(II)/Ni(II)-sensitive mechanisms. F. nucleatum is an anaerobic bacteria present in the plaque. It leads not only to periodontal diseases but also, angina, purulent inflammation of the lung tissue or reproductive organs [10]. Moreover, F. nucleatum promotes colon cancer growth [11]. This bacteria strain promotes inflammation and tumorigenesis by modulating the tumor immune microenvironment [12, 13]. Microbial pathogens drive tumorigenesis in 15–20% of cancer cases [14]. However, not only microorganisms are considered a major risk factor, but also metal ions play an important role in tumor promotion [15, 16]. Therefore, our primary research goal is to investigate the effect of metal ions coordination on the activity of outer-membrane proteins from F. nucleatum and to answer whether these proteins increase the prooxidative activity of Cu(II) and Fe(II) ions [16-18].

Three Ways Ashore: Where Did Terrestrial Plants, Arthropods and Vertebrates Come from? Are Essentiality Patterns of Chemical Elements Living Bio(-Geo)chemical "Fossils"? - Inferences from Essentiality Patterns and the Biological System of Elements

Franzle S., Markert B.

Chemia i Inżynieria Ekologiczna

2002

Vol. 9, nr 9

949-967

Among other topics the Biological System of Elements [3] comprehensively describes the distribution of chemical elements in glycophyte plants, regardless whether these elements are essential, (presumably) non-essential or outright toxic. This approach has also been applied to other taxa, phyla and even kingdoms. However, comparisons among different kingdoms of organisms which separated about one billion years ago (fungi, algae, higher plants, animals) show large differences among the sets of essential elements. Thus evolutionary changes render it impossible to reconstruct the whereabouts of the ancestors of groups of recent organisms (geochemical palaeoecology) from comparisons of element essentialities Ys. the relative abundances of these and other elements in sea- and fresh water, respectively. Losses of ions from the tissues of fresh-water fishes are controlled by the extent of complexation. The selection pressure to go ashore was larger in fresh water. Probably the number of essential elements was larger soon after evolution of metazoans, adaptation to live with fewer ones being most pronounced in fungi.

Wśród innych obecnie rozpatrywanych podejść, Biologiczny System Pierwiastków Chemicznych (BSE) zrozumiale opisuje podział pierwiastków chemicznych w roślinach glikofitowych, bez względu na to, czy te pierwiastki są istotne, (przypuszczalnie) nieistotne lub też ewidentnie toksyczne. Takie podejście zastosowano również do innych grup taksonomicznych i gromad, a nawet królestw. Jednak porównania różnych królestw organizmów, które rozdzieliły się ok. l miliarda lat temu (grzyby, algi, rośliny wyższe, zwierzęta), pokazują duże różnice między zestawieniami pierwiastków istotnych. A zatem zmiany ewolucyjne sprawiają, że nie jest możliwa rekonstrukcja miejsca przebywania przodków współczesnych grup organizmów (paleontologia geochemiczna) poprzez porównanie względnego rozpowszechnienia w nich pierwiastków istotnych oraz innych pierwiastków z takimi danymi dla wody słodkiej i morskiej. Ubytki jonów z tkanek ryb słodkowodnych są kontrolowane przez zakres ich skompleksowania. Napór do wyjścia na ląd był większy dla organizmów słodkowodnych. Prawdopodobnie liczba pierwiastków istotnych była większa krótko po pojawieniu się tkankowców. Adaptacja do życia z mniejszą liczbą tych pierwiastków jest najbardziej wyraźna u grzybów.