Amoebozoa - Science topic

Myxomycetes (plasmodial slime molds, or myxogastrids) are phagotrophic amoeboid eukaryotes in the Eumycetozoa, in phylum Amoebozoa. Eumycetozoa is includes Myxogastria, Dictyostelia, and Protostelia. Slime molds are divided into two groups: acellular slime molds (Myxogastria and Protostelia) and cellular slime molds (Dictyostelium) (Willey et al.,...

Free living amoebae (FLA) are ubiquitous and found in many types of environments including soil, freshwater, air and marine environments. They feed on various microorganisms, and can play a key central role in the food web and its dynamic. We described previously that FLA belonging to the Vannella genus from the oyster farming area of the Thau lago...

Translation is a sine qua non process for life as we know it. Translation factors (TFs) and tRNAs are rare among viruses but are commonly found in giant viruses of the class Megaviricetes. In this study, we explored the diversity and distribution of tRNAs in giant viruses that were isolated and replicated in amoebae (phylum Amoebozoa), and investig...

True slime molds (Eumycetozoa) represent a monophyletic clade within the phylum Amoebozoa, comprising the lineages Myxogastria, Dictyostelia, and Protosporangiida. Although historically misclassified as fungi, recent molecular and biochemical studies underscore their distinct evolutionary trajectories and rich metabolomic profiles. In this review,...

Glucose metabolism is a key factor characterizing the cellular state during multicellular development. In metazoans, the metabolic state of undifferentiated cells correlates with growth/differentiation transition and cell fate determination. Notably, the cell fate of the Amoebozoa species Dictyostelium discoideum is biased by the presence of glucos...

We aimed to understand how testaceous amoebae spread in new sites, assessing their dispersal potential by wind and animals in freshwater ecosystems. We conducted a field experiment over 33 days between July and August 2018. The study included four different approaches: (i) a control group exposed exclusively to wind, (ii) the addition of propagules...

The representatives of the archamoebian genus Pelomyxa are amoeboid anaerobic protists that inhabit fresh-water anoxic sediments, and most of them are usually multinucleate. The cytoplasm of these unicellular organisms is highly complicated and contains numerous vacuoles of different types, as well as a wide range of prokaryotic endocytobionts, agg...

Parasitic infections in non-human primates (NHPs) kept ex situ can be caused by zoonotic protists like Balantioides coli and Entamoeba histolytica. In Brazil, little is known about these infections in neotropical species. This study aimed to identify Amoebozoa and Ciliophora groups in fecal samples through in vitro isolation and molecular analysis,...

The need for high-quality protist genomes has prevented in-depth computational and experimental studies of giant virus–host interactions. In addition, our current knowledge of host range is highly biased due to the few hosts used to isolate novel giant viruses. This study presents 6 high-quality amoeba genomes from known and potential giant virus h...

Since Georges Deflandre published his monograph on the genus Nebela in 1936 no systematic revision of this beautiful group of testate amoebae had been done. In the meantime, the genus was split, and many new species were described. A taxonomic revision was clearly overdue. In this monograph, we present a taxonomic revision of the sub-order Hyalosph...

Soil microbial communities are crucial to ecosystem functionality, influencing soil fertility and health. Microbial diversity in soil is impacted by various land-use practices and environmental conditions, but the effects on both prokaryotic and eukaryotic communities remain insufficiently understood. This study investigates the influence of differ...

Here we reassess available evidence for the long-held misconception of amoebae possessing exceptionally large genomes. Traditionally, estimates relied on inaccurate methods like DNA weight measurements, leading to inflated sizes. These methods failed to account for contaminating DNA from prey, endosymbionts, and intrinsic genomic features like ribo...

The pseudostem weevil Odoiporus longicollis being a major pest of banana confers a serious loss to the crop. The cellulose- and terpene-laden diet demands a high reliance on gut microbiome to platter the nutrition. Here we investigated the whole microbiome of foregut, midgut and hindgut of O. longicollis to understand the spatial distribution of mi...

We present the results of a combined investigation of the dynamics of movement and spatial structure of the actin cytoskeleton in Pellita digitata (Penard, 1902) Smirnov and Kudryavtsev, 2005. A combination of differential interference contrast light microscopy, transmission electron microscopy based on oriented sectioning of the cells adhering to...

Amoebozoa is a group of single-celled organisms that change their shape during locomotion. However, there is a taxon-specific complex of morphological characters inherent in the moving amoebae, known as locomotive forms. Actin is one of the proteins most important for amoeboid movement that, together with actin-binding proteins, construct the archi...

The cellular slime mold Dictyostelium discoideum, a member of the Amoebozoa, has been extensively studied in cell and developmental biology. D. discoideum is unique in that they are genetically tractable, with a wealth of data accumulated over half a century of research. Fluorescence live-cell imaging of D. discoideum has greatly facilitated studie...

Overview of the Amoebozoa

Background In trypanosomatids, a group of unicellular eukaryotes that includes numerous important human parasites, cis-splicing has been previously reported for only two genes: a poly(A) polymerase and an RNA helicase. Conversely, trans-splicing, which involves the attachment of a spliced leader sequence, is observed for nearly every protein-coding...

We isolated a new strain of an amoebozoan, Ptolemeba bulliensis Watson et al., 2014 (Tubulinea) from the gills of farmed rainbow trout ( Oncorhynchus mykiss Walbaum, 1792) showing signs of nodular gill disease. The studied strain can be identified using morphological and molecular (small subunit ribosomal RNA gene sequence data) characters. We obta...

The objective of this study was to evaluate the effect of three carbon sources: molasses (Control), tapioca flour and banana peel, for the development of a biofloc system in the culture of the ornamental fish Puntius tetrazona. To ensure floc formation, a C/N ratio=20:1 was maintained for each of the carbon sources, considering three replicates per...

Updates of the eukaryotic system (domain Eukarya) in the interface “Eukaryotic supergroups: Taxonomy/Biotechnology interface” are described. The nine-kingdom system Eukarya has the following form: subdomain Excavata (kingdoms Archezoa, Discoba), subdomain Obimoda (kingdoms Crumalia, Amoebozoa, Obazoa), subdomain Corticata (kingdoms Eocorticata, Hap...

Subkingdom Protozoa represents a significant taxonomic category, comprising of various parasitic members. Globally, there are approximately 50,000 described species of protozoa, with only 11,000 exhibiting parasitic behavior. In India, 29 parasitic species of phylum Bigyra and 18 parasitic species of phylum Amoebozoa have been documented. This stud...

The cellular slime mold Dictyostelium discoideum , a member of the Amoebozoa, has been extensively studied in cell and developmental biology. D. discoideum is unique in that they are genetically tractable, with a wealth of data accumulated over half a century of research. Fluorescence live-cell imaging of D. discoideum has greatly facilitated studi...

Restoring native ecosystems on marginal croplands has many benefits but the impacts on belowground biodiversity are less clear, in part because the limiting factors regulating soil biota are complex and poorly described. Here, we studied how grassland prairie restoration of marginal croplands affected the diversity and composition of soil microbiot...

Myxomycetes are amoeboid fungus-like organisms (Amoebozoa) with a unique life cycle characterized by a great morphological diversity of fruiting bodies. Due to the similarity of these structures to the fruiting bodies of some representatives of Ascomycota and Basidiomycota, myxomycetes have been classified as fungi since the first known scientific...

The need for high-quality protist genomes has prevented in-depth computational and experimental studies of giant virus-host interactions. In addition, our current knowledge of host range is highly biased due to the few hosts used to isolate novel giant viruses. This study presents six high-quality amoeba genomes from known and potential giant virus...

Paper ID: IRCUWU2024-178 Poster Assessment of zooplankton diversity in Iranamadu Reservoir, Kilinochchi in the Northern Province, Sri Lanka A. Ganeshwaranathan1Q, H.A.C.C. Perera2 1National Aquaculture Development Authority (NAQDA), Iranamadu, Kilinochchi, Sri Lanka 2Department of Zoology and Environmental Management, University of Kelaniya, Daluga...

Eukaryotes evolved from prokaryotic predecessors in the early Proterozoic and radiated from their already complex last common ancestor, diversifying into several supergroups with unresolved deep evolutionary connections. They evolved extremely diverse lifestyles, playing crucial roles in the carbon cycle. Heterotrophic flagellates are arguably the...

Entamoeba histolytica is a protozoan parasite belonging to the phylum Amoebozoa that causes amebiasis, a global public health problem. E. histolytica alternates its form between a proliferative trophozoite and a dormant cyst. Trophozoite proliferation is closely associated with amebiasis symptoms and pathogenesis whereas cysts transmit the disease....

Background Bioaugmentation is considered a sustainable and cost-effective methodology to recover contaminated environments, but its outcome is highly variable. Predation is a key top-down control mechanism affecting inoculum establishment, however, its effects on this process have received little attention. This study focused on the impact of troph...

Photosymbioses, the symbiotic relationships between photosynthetic algal symbionts and non- photosynthetic eukaryotic hosts, are sporadically found in a lot of eukaryotic lineages, but only a few taxa, such as cnidarians and ciliates hosting algal endosymbionts, have been actively studied for a long time. That has hindered understanding the univers...

The relationship between the protozoan communities and environmental variables was studied in the Nile River to evaluate their potential as water quality indicators. Protozoans were sampled monthly at six sampling sites in the Nile's Damietta Branch across a spatial gradient of environmental conditions during a 1-year cycle (February 2016–January 2...

The diversity of amoebae of the genus Polychaos comprises a group of three hardly distinguishable "Polychaos fasciculatum-like" species: P. annulatum, P. fasciculatum and Metachaos gratum. Polychaos annulatum was twice re-isolated and thoroughly studied. There is little data on P. fasciculatum, and M. gratum has never been investigated since its de...

Entamoeba histolytica is a protozoan parasite that belongs to the Amoebozoa supergroup whose study related to the nucleocytoplasmic transport of proteins through the nucleus is poorly studied. In this work, we have performed in silico predictions of the potential nuclear localization signals (NLS) corresponding to the proteome of 8201 proteins from...

Until recently, it was believed that amoebae of the genus Thecamoeba Fromentel, 1874 could be relatively easily distinguished from each other at the light-microscopic level. The main characteristics were the shape and size of the locomotive form and the morphology of the nucleus. However, recent studies with molecular methods have shown that severa...

Plasmalogens are glycerophospholipids with a vinyl ether bond, rather than an ester bond, at sn-1 position. These lipids were described in anaerobic bacteria, myxobacteria, animals and some protists, but not in plants or fungi. Anaerobic and aerobic organisms synthesize plasmalogens differently. The aerobic pathway requires oxygen in the last step,...

Background The folate cycle of one-carbon (C1) metabolism, which plays a central role in the biosynthesis of nucleotides and amino acids, demonstrates the significance of metabolic adaptation. We investigated the evolutionary history of the methylenetetrahydrofolate dehydrogenase (mTHF) gene family, one of the main drivers of the folate cycle, acro...

La Estación Biológica Agua Zarca (EBAZ) resguarda parte de la biodiversidad de Aguascalientes (México); sin embargo, no existían registros específicos de los macromicetes del lugar. La importancia de este estudio fue descubrir y conocer la riqueza de los hongos macroscópicos de la EBAZ. Durante la temporada de lluvia de 2021 y 2022 se realizaron re...

La Estación Biológica Agua Zarca (EBAZ) resguarda parte de la biodiversidad de Aguascalientes (México); sin embargo, no existían registros específicos de los macromicetes del lugar. La importancia de este estudio fue descubrir y conocer la riqueza de los hongos macroscópicos de la EBAZ. Durante la temporada de lluvia de 2021 y 2022 se realizaron re...

Light and scanning electron microscopy were applied to re-assess diagnostic characters of type specimens and critical specimens of Diachea radiata, D. splendens, D. subsessilis, Diderma arboreum, Didymium. laxifilum, D. leoninum var. effusum, D. trachysporum, D. trochus, Physarum bitectum, P. straminipes, Reticularia intermedia, R. jurana, R. liceo...

Bioaugmentation is considered as a sustainable and cost-effective methodology to recover contaminated environments, but its outcome is highly variable. Predation is a key top-down control mechanism affecting inoculum establishment, however its effects on this process have received little attention. This study focused on the impact of trophic intera...

Ceratiomyxa morchella, characteristic of the Neotropical myxobiota, was first recorded in Brazil four decades ago in the northern region of the country. Since then, it has a known distribution only in the North and Northeast regions, occurring in the Amazon and Atlantic Forest biomes. Collecting carried out in a fragment of Mixed Ombrophylous Fores...

Under irrigation with saline wastewater, SO4²⁻, Cl⁻, and Ca²⁺ aggregated in the topsoil, and Mg²⁺ was significantly higher in the deeper soil than in the topsoil and 40 cm soil layers. The abundance of Zoopagomycota, Ascomycota, Mortierellomycota, Basidiomycota, Chytridiomycota, Rozellomycota, Blastocladiomycota, Monoblepharomycota, Mucoromycota an...

Las amibas de vida libre (AVL) se definen como un grupo de protozoarios aeróbicos ampliamente distribuidos en la naturaleza (agua, aire y suelo de todos los continentes). Éstas se encuentran clasificadas taxonómicamente en los supergrupos: Amoebozoa: Acanthamoebidae (en el que se engloban la mayoría de las especies de AVL y que contiene a los géner...

The River Nile is the main source of fresh water in Egypt, where its water is used for irrigation, drinking, fisheries, industrial uses, and recreation. For sustainable utilization of the River Nile and its branches in the Nile Delta region, it is necessary to monitor regular investigation for the biodiversity of protozoan fauna in the Damietta bra...

MicroRNAs (miRNAs) are important and ubiquitous regulators of gene expression in both plants and animals. They are thought to have evolved convergently in these lineages and hypothesized to have played a role in the evolution of multicellularity. In line with this hypothesis, miRNAs have so far only been described in few unicellular eukaryotes. Her...

The Tatra Mts are the highest mountain range in the Carpathians and are an important biodiversity region for many organisms. Plants, animals, and fungi are better studied in this region, while myxomycetes still remain understudied. This study presents the most up-to-date checklist of myxomycetes in the Polish Tatra Mts. The list is based on the pub...

The nivicolous species of the genus Diderma are challenging to identify, and there are several competing views on their delimitation. We analyzed 102 accessions of nivicolous Diderma spp. that were sequenced for two or three unlinked genes to determine which of the current taxonomic treatments is better supported by molecular species delimitation m...

El propósito de este libro es recordar que en el mundo de la medicina hay un constante surgimiento de enfermedades, algunas de ellas con una cronicidad de miles de años que, al no poderse erradicar de la humanidad, tienden a ser olvidadas y pasan a formar un grupo que los científicos actuales clasifican como “enfermedades tropicales olvidadas” (neg...

Background Reductive soil disinfestation (RSD) is an effective agricultural practice to improve the soil microbial community. However, most RSD research has focused on single bacteria or fungi, little is known about the combined influence on the entire microbiome, particularly impacts on protists and the relationships of these groups linked to plan...

Brilliant colors in nature arise from the interference of light with periodic nanostructures resulting in structural color. While such biological photonic structures have long attracted interest in insects and plants, they are little known in other groups of organisms. Unexpected in the kingdom of Amoebozoa, which assembles unicellular organisms, s...

Studies of the diversity of myxomycetes or plasmodial slime moulds (Amoebozoa) in New Brunswick are lagging behind those of many other groups of terrestrial organisms. Here, we summarize the myxomycetes of the province as documented by recently collected specimens held by the New Brunswick Museum (NBM). Between 2007 and 2019, 264 specimens were col...

Most eukaryotic microbial biodiversity is undescribed, and most species might be morphologically indistinguishable. Notable exceptions are so-called flagship species which are highly conspicuous and can therefore be used to address biogeographical questions. Here we describe Hyalosphenia papilio subsp. paynei, an arcellinid testate amoeba (Amoebozo...

The class Myxomycetes consists of free-living protists characterised by their complex life cycle, which includes both microscopic (amoebae, flagellates and cists) and macroscopic stages (spore-bearing fruiting bodies, sclerotia, and plasmodia). Within it, the order Physarales , with more than 450 recognised species, constitutes the largest group. A...

Los Myxomycetes son un grupo de protistas ameboides que intervienen en la descomposición de materia orgánica de origen vegetal. En Perú se han registrado alrededor del 22% de las especies conocidas a nivel mundial, pero el territorio está estudiado de forma desigual y los bosques tropicales amazónicos, en particular la selva central peruana, apenas...

Perilipins are abundant lipid droplet (LD) proteins present in all metazoans, and also in amoebozoa and fungi. Humans express five perilipins, which share a similar domain organization: an amino‐terminal PAT domain and an 11‐mer repeat region, which can fold into amphipathic helices that interact with LDs, followed by a structured carboxy‐terminal...

The de novo synthesis of dTTP uses several pathways: gram-negative bacteria use dCTP deaminase (Dcd) to convert dCTP into dUTP, whereas eukaryotes and gram-positive bacteria instead use dCMP deaminase to transform dCMP to dUMP. It is then unusual that in addition to dCMP deaminases, the eukaryote Dictyostelium discoideum has two dCTP deaminases (Dc...

Amoebae of the genus Dermamoeba can frequently be isolated from terrestrial and freshwater habitats. They have oval or lingulate outlines and a smooth dorsal surface. The thick cell coat of these organisms is a complex, multilayered glycocalyx. Nowadays, three species within the genus Dermamoeba are recognized, with molecular data available for jus...

Recent phylogenetic studies indicate taxonomic uncertainty of some species in the genera Arcyria (Arcyriaceae) and Trichia (Trichiaceae). For example, a phylogenetic position of Trichia brunnea still is not resolved. We revised a taxonomic position of this species based on extensively sampled 18S nrDNA sequences, as well as a morphological analysis...

Seasonal dynamics of microzooplankton and changes in environmental condition were analysed during a one-year field sampling campaign in the Sea of Oman at two different stations. Monsoon winds in this region cause distinct seasonality patterns with high primary productivity during the southwest monsoon in summer (June to October) and northeast mons...

Prevailing social, economic and political ideas and paradigms constitute the lens through which scientists observe, assess, and understand the world. This affects how we interpret and understand the mechanisms governing the interaction between organisms and has led, in most cases, to dominant explanations and paradigms that are difficult to overthr...

Amoeboid cell movement and migration are wide-spread across various cell types and species. Microscopy-based analysis of the model systems Dictyostelium and neutrophils over the years have uncovered generality in their overall cell movement pattern. Under no directional cues, the centroid movement can be quantitatively characterized by their persis...

The presence of microbial communities on cave walls and speleothems is an issue that requires attention. Traditional cleaning methods using water, brushes, and steam can spread the infection and cause damage to the cave structures, while chemical agents can lead to the formation of toxic compounds and damage the cave walls. Essential oils have show...

ATAD3 proteins (ATPase family AAA domain-containing protein 3) are unique mitochondrial proteins that arose deep in the eukaryotic lineage but that are surprisingly absent from the Fungi and Amoebozoa. These ~600 amino acid proteins are anchored in the inner mitochondrial membrane and are essential in metazoans and Arabidopsis thaliana. ATAD3s comp...

MicroRNAs (miRNAs) are important and ubiquitous regulators of gene expression in both plants and animals. They are thought to have evolved convergently in these lineages and hypothesized to have played a role in the evolution of multicellularity. In line with this hypothesis, miRNAs have so far only been described in few unicellular eukaryotes. Her...

Predatory protists are widely recognized as critical biotic forces driving soil microbial communities, but their top‐down controls on ammonia‐oxidizing microorganisms (AOMs), the major players in nitrification, are largely unresolved. Here, we investigated the communities of predatory protists and their associations with AOMs using high‐throughput...

The northeastern edge of the Tibetan Plateau exhibits diverse climate and landform variations, and has experienced substantial recent environmental changes, which may significantly impact local agricultural practices. Understanding the microeukaryote community structure within agricultural soils is crucial for finding out the biological responses t...

Testate amoebae Cyclopyxis puteus Thomas (1960) has a characteristic morphology, that makes the possibility of overlook or misidentification unlikely. Although this species has been found worldwide, its morphology, biometrics and ecological preferences are poorly understood. In this study, isolated material from Bulgaria was investigated by using l...

Amoeboid cell movement and migration are wide-spread across various cell types and species. Microscopy-based analysis of the model systems Dictyostelium and neutrophils over the years have uncovered generality in their overall cell movement pattern. Under no directional cues, the centroid movement can be quantitatively characterized by their persis...

Background: Legionella are parasites of freshwater protozoa, responsible for Legionellosis. Legionella can be found in a variety of aquatic environments, including rivers, lakes, and springs, as well as in engineered water systems where they can potentially lead to human disease outbarks. Legionella are considered to be predominantly freshwater or...

Copromyxa flindersi sp. nov. was isolated from the freshwater river bottom sediment sample collected at Kangaroo Island (Australia). The studied amoeba mostly resembles Copromyxa limacoides (Page, 1967) in its light and electron microscopical characteristics. Phylogenetic analyses based on the 18S rRNA and Cox1 genes show that this species is most...

In the context of the soil food web, the transfer of plant-fixed energy and carbon to higher trophic levels has traditionally been attributed to two main energy channels: the fungal energy channel and the bacterial energy channel. Historically, protists were overlooked in the fungal energy channel, which was believed to be controlled by fungivorous...

The salinity and humidity barriers divide biodiversity and strongly influence the distribution of organisms. Crossing them opens the possibility for organisms to colonize new niches and diversify, but requires profound physiological adaptations and is supposed to happen rarely in evolutionary history. We tested the relative importance of each ecolo...

Long-term fertilization affects soil organic C accumulation. A growing body of research has revealed critical roles of bacteria in soil organic C accumulation, particularly through mineral-associated organic C (MAOC) formation. Protists are essential components of soil microbiome, but the relationships between MAOC formation and protists under long...

Aquifer systems are composed of water flowing from surface recharge areas, to the subsurface and back to the surface in discharge regions. Groundwater habitats harbor a large microbial biomass and diversity, potentially contributing to surface aquatic ecosystems. Although this contribution has been widely studied in marine environments, very little...

The diverse GTPases of the dynamin superfamily play various roles in the cell, as exemplified by the dynamin-related proteins (DRPs) Mgm1 and Opa1, which remodel the mitochondrial inner membrane in fungi and metazoans, respectively. Via an exhaustive search of genomic and metagenomic databases we found previously unknown DRP types occurring in dive...

The paper presents data on the distribution and species diversity of myxomycetes in the territory of the “Nizhnyaya Kama” National Park and its surroundings during early autumn of 2021 and 2022. A total of 40 species of myxomycetes were found in the unique spruce-alder ravine ecotopes and coniferous-broadleaved forest communities of the National Pa...

Amoebozoa include lineages of diverse ecology, behavior, and morphology. They are assumed to encompass members with the largest genome sizes of all living things, yet genomic studies in the group are limited. Trichosphaerium, a polymorphic, multinucleate, marine amoeba with a complicated life cycle, has puzzled experts for over a century. In an eff...

During an investigation of amoeba rDNA sequences, a group I intron was identifi ed in the 18S rDNA of Thecamoeba aesculea (Amoebozoa; Discosea) at position S956. Secondary structure of Thecamoeba intron and phylogenetic analysis suggest that it is affi liated with other S956 introns occurring in distantly related amoebae such as acrasid (Percolozoa...

Oncogenesis and the origin of cancer are still not fully understood despite the efforts of his-tologists, pathologists, and molecular geneticists to determine how cancer develops. Previousembryogenic and gene- and genome-based hypotheses have attempted to solve this enigma.Each of them has its kernel of truth, but a unifying, universally accepted t...

Myxogastrea is a group of eukaryotic microorganisms included in Amoebozoa. Its life cycle includes two trophic stages: plasmodia and myxamoeflagellates. However, only about 102 species have their complete life cycle known in literature and only about 18 species have their plasmodial axenic culture accomplished in laboratory conditions. The research...

The genus Schizoplasmodiopsis is one of the most morphologically diverse groups among the class Variosea. Recent phylogenetic studies suggest that Schizoplasmodiopsis is polyphyletic, but there are few taxonomic studies of this genus. We established S. micropunctata strain YIP-40, observed in detail its of morphology and lifecycle, and conducted a...