Cell – Structure and Functions
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The Morphology, Ultrastructure and Molecular Phylogeny of a New Freshwater Heterolobose Amoeba Parafumarolamoeba Stagnalis N. Sp
diversity Article The Morphology, Ultrastructure and Molecular Phylogeny of a New Freshwater Heterolobose Amoeba Parafumarolamoeba stagnalis n. sp. (Vahlkampfiidae; Heterolobosea) Anastasia S. Borodina 1,2, Alexander P. Mylnikov 1,†, Jan Janouškovec 3 , Patrick J. Keeling 4 and Denis V. Tikhonenkov 1,5,* 1 Papanin Institute for Biology of Inland Waters, Russian Academy of Sciences, 152742 Borok, Russia; [email protected] 2 Department of Zoology and Parasitology, Voronezh State University, Universitetskaya Ploshad 1, 394036 Voronezh, Russia 3 Centre Algatech, Laboratory of Photosynthesis, Institute of Microbiology, Czech Academy of Sciences, Opatovický Mlýn, 37981 Tˇreboˇn,Czech Republic; [email protected] 4 Department of Botany, University of British Columbia, 6270 University Boulevard, Vancouver, BC V6T1Z4, Canada; [email protected] 5 AquaBioSafe Laboratory, University of Tyumen, 625003 Tyumen, Russia * Correspondence: [email protected]; Tel.: +7-485-472-4533 † Alexander P. Mylnikov is deceased. http://zoobank.org/References/e543a49a-16c1-4b7c-afdb-0bc56b632ef0 Abstract: Heterolobose amoebae are important members of marine, freshwater, and soil microbial Citation: Borodina, A.S.; Mylnikov, communities, but their diversity remains under-explored. We studied the diversity of Vahlkampfiidae A.P.; Janouškovec, J.; Keeling, P.J.; to improve our understanding of heterolobosean relationships and their representation in aquatic Tikhonenkov, D.V. The Morphology, benthos. Using light and electron microscopy, and molecular phylogenies based on the SSU rRNA Ultrastructure and Molecular and ITS loci, we describe the fine morphology and evolutionary relationships of a new heterolobosean Phylogeny of a New Freshwater Parafumarolamoeba stagnalis n. sp. from a small pond in European Russia. Cells of P. stagnalis possess Heterolobose Amoeba a clearly distinguishable anterior hyaline pseudopodium, eruptive movement, several thin and Parafumarolamoeba stagnalis n. -
The Intestinal Protozoa
The Intestinal Protozoa A. Introduction 1. The Phylum Protozoa is classified into four major subdivisions according to the methods of locomotion and reproduction. a. The amoebae (Superclass Sarcodina, Class Rhizopodea move by means of pseudopodia and reproduce exclusively by asexual binary division. b. The flagellates (Superclass Mastigophora, Class Zoomasitgophorea) typically move by long, whiplike flagella and reproduce by binary fission. c. The ciliates (Subphylum Ciliophora, Class Ciliata) are propelled by rows of cilia that beat with a synchronized wavelike motion. d. The sporozoans (Subphylum Sporozoa) lack specialized organelles of motility but have a unique type of life cycle, alternating between sexual and asexual reproductive cycles (alternation of generations). e. Number of species - there are about 45,000 protozoan species; around 8000 are parasitic, and around 25 species are important to humans. 2. Diagnosis - must learn to differentiate between the harmless and the medically important. This is most often based upon the morphology of respective organisms. 3. Transmission - mostly person-to-person, via fecal-oral route; fecally contaminated food or water important (organisms remain viable for around 30 days in cool moist environment with few bacteria; other means of transmission include sexual, insects, animals (zoonoses). B. Structures 1. trophozoite - the motile vegetative stage; multiplies via binary fission; colonizes host. 2. cyst - the inactive, non-motile, infective stage; survives the environment due to the presence of a cyst wall. 3. nuclear structure - important in the identification of organisms and species differentiation. 4. diagnostic features a. size - helpful in identifying organisms; must have calibrated objectives on the microscope in order to measure accurately. -
A Revised Classification of Naked Lobose Amoebae (Amoebozoa
Protist, Vol. 162, 545–570, October 2011 http://www.elsevier.de/protis Published online date 28 July 2011 PROTIST NEWS A Revised Classification of Naked Lobose Amoebae (Amoebozoa: Lobosa) Introduction together constitute the amoebozoan subphy- lum Lobosa, which never have cilia or flagella, Molecular evidence and an associated reevaluation whereas Variosea (as here revised) together with of morphology have recently considerably revised Mycetozoa and Archamoebea are now grouped our views on relationships among the higher-level as the subphylum Conosa, whose constituent groups of amoebae. First of all, establishing the lineages either have cilia or flagella or have lost phylum Amoebozoa grouped all lobose amoe- them secondarily (Cavalier-Smith 1998, 2009). boid protists, whether naked or testate, aerobic Figure 1 is a schematic tree showing amoebozoan or anaerobic, with the Mycetozoa and Archamoe- relationships deduced from both morphology and bea (Cavalier-Smith 1998), and separated them DNA sequences. from both the heterolobosean amoebae (Page and The first attempt to construct a congruent molec- Blanton 1985), now belonging in the phylum Per- ular and morphological system of Amoebozoa by colozoa - Cavalier-Smith and Nikolaev (2008), and Cavalier-Smith et al. (2004) was limited by the the filose amoebae that belong in other phyla lack of molecular data for many amoeboid taxa, (notably Cercozoa: Bass et al. 2009a; Howe et al. which were therefore classified solely on morpho- 2011). logical evidence. Smirnov et al. (2005) suggested The phylum Amoebozoa consists of naked and another system for naked lobose amoebae only; testate lobose amoebae (e.g. Amoeba, Vannella, this left taxa with no molecular data incertae sedis, Hartmannella, Acanthamoeba, Arcella, Difflugia), which limited its utility. -
Experimental Listeria–Tetrahymena–Amoeba Food Chain Functioning Depends on Bacterial Virulence Traits Valentina I
Pushkareva et al. BMC Ecol (2019) 19:47 https://doi.org/10.1186/s12898-019-0265-5 BMC Ecology RESEARCH ARTICLE Open Access Experimental Listeria–Tetrahymena–Amoeba food chain functioning depends on bacterial virulence traits Valentina I. Pushkareva1, Julia I. Podlipaeva2, Andrew V. Goodkov2 and Svetlana A. Ermolaeva1,3* Abstract Background: Some pathogenic bacteria have been developing as a part of terrestrial and aquatic microbial eco- systems. Bacteria are consumed by bacteriovorous protists which are readily consumed by larger organisms. Being natural predators, protozoa are also an instrument for selection of virulence traits in bacteria. Moreover, protozoa serve as a “Trojan horse” that deliver pathogens to the human body. Here, we suggested that carnivorous amoebas feeding on smaller bacteriovorous protists might serve as “Troy” themselves when pathogens are delivered to them with their preys. A dual role might be suggested for protozoa in the development of traits required for bacterial passage along the food chain. Results: A model food chain was developed. Pathogenic bacteria L. monocytogenes or related saprophytic bacteria L. innocua constituted the base of the food chain, bacteriovorous ciliate Tetrahymena pyriformis was an intermedi- ate consumer, and carnivorous amoeba Amoeba proteus was a consumer of the highest order. The population of A. proteus demonstrated variations in behaviour depending on whether saprophytic or virulent Listeria was used to feed the intermediate consumer, T. pyriformis. Feeding of A. proteus with T. pyriformis that grazed on saprophytic bacteria caused prevalence of pseudopodia-possessing hungry amoebas. Statistically signifcant prevalence of amoebas with spherical morphology typical for fed amoebas was observed when pathogenic L. -
Can Protozoa Prove the Beginning of the World?
Southeastern University FireScholars Classical Conversations Spring 2020 Can Protozoa Prove the Beginning of the World? Karina L. Burton Southeastern University - Lakeland, [email protected] Follow this and additional works at: https://firescholars.seu.edu/ccplus Part of the Cell Biology Commons, and the Evolution Commons Recommended Citation Burton, Karina L., "Can Protozoa Prove the Beginning of the World?" (2020). Classical Conversations. 9. https://firescholars.seu.edu/ccplus/9 This Term Paper is brought to you for free and open access by FireScholars. It has been accepted for inclusion in Classical Conversations by an authorized administrator of FireScholars. For more information, please contact [email protected]. 1 Can Protozoa Prove the Beginning of the World? Karina L. Burton Classical Conversations: Challenge 4; Southeastern University ENGL 1233: English Composition II Grace Veach April 16, 2020 2 Abstract Protozoa are magnificent creatures. They exhibit all of the functions intrinsic to living organisms: irritability, metabolism, growth and reproduction. Within these functions, there are numerous examples of mutations that occur in order for organisms to adapt to their given environments. Irritability is demonstrated in protozoa by their use of pseudopodia, flagella, or cilia for motility; it has been shown that such locomotors exhibit diversity while maintaining similar protein and chemical structures that appear to be a result of evolutionary processes. Metabolism in protozoa is similar to that of larger animals, but their diet is unique. They primarily feast upon bacteria, which have begun mutating to evade easy ingestion and digestion by protozoa, therefore increasing their survival rate and making it necessary for protozoa to adapt. -
CH28 PROTISTS.Pptx
9/29/14 Biosc 41 Announcements 9/29 Review: History of Life v Quick review followed by lecture quiz (history & v How long ago is Earth thought to have formed? phylogeny) v What is thought to have been the first genetic material? v Lecture: Protists v Are we tetrapods? v Lab: Protozoa (animal-like protists) v Most atmospheric oxygen comes from photosynthesis v Lab exam 1 is Wed! (does not cover today’s lab) § Since many of the first organisms were photosynthetic (i.e. cyanobacteria), a LOT of excess oxygen accumulated (O2 revolution) § Some organisms adapted to use it (aerobic respiration) Review: History of Life Review: Phylogeny v Which organelles are thought to have originated as v Homology is similarity due to shared ancestry endosymbionts? v Analogy is similarity due to convergent evolution v During what event did fossils resembling modern taxa suddenly appear en masse? v A valid clade is monophyletic, meaning it consists of the ancestor taxon and all its descendants v How many mass extinctions seem to have occurred during v A paraphyletic grouping consists of an ancestral species and Earth’s history? Describe one? some, but not all, of the descendants v When is adaptive radiation likely to occur? v A polyphyletic grouping includes distantly related species but does not include their most recent common ancestor v Maximum parsimony assumes the tree requiring the fewest evolutionary events is most likely Quiz 3 (History and Phylogeny) BIOSC 041 1. How long ago is Earth thought to have formed? 2. Why might many organisms have evolved to use aerobic respiration? PROTISTS! Reference: Chapter 28 3. -
A PRELIMINARY NOTE on TETRAMITUS, a STAGE in the LIFE CYCLE of a COPROZOIC AMOEBA by MARTHA BUNTING
294 Z6OL6G Y.- M. BUNTING PROC. N. A. S. A PRELIMINARY NOTE ON TETRAMITUS, A STAGE IN THE LIFE CYCLE OF A COPROZOIC AMOEBA By MARTHA BUNTING DEPARTMENT OF ZOOLOGY, UNIVERSITY OF PENNSYLVANIA Communicated July 24, 1922 In 1920 a study of the Entamoeba of the rat was begun and in a culture on artificial medium a number of Coprozoic amoeba appeared, one of which exhibited a flagellate phase which seems to be identical with Tetramitus rostratus Perty.1 The appearance of flagellate phases in cultures of Coprozoic amoeba (Whitmore,2 etc.) as well as of soil amoeba (Kofoid,1 Wilson,4 etc.) has been recorded a number of times, but the flagellates which appeared were relatively simple in organization and very transitory in occurrence. Fur- thermore, some of the simpler flagellates have been observed (Pascher5) to lose their flagella and become amoeboid. In the case here described, however, there is a transformation of a simple amoeba into a relatively complex flagellate which multiplies for several days then returns to the amoeboid condition and becomes encysted. Tetramitus rostratus has been studied by a number of investigators since its discovery in 1852, by Perty,' yet no one has given a full account of its life history. The lack of cysts in previous accounts, mentioned by Dobell and O'Connor,6 is explained by the transformation into an amoeba before encystment. It is believed that this animal presents the extreme in transformations of this sort and serves to emphasize the close relationship between amoebae and flagellates, and the need for careful studies of life cycles, in pure cultures where possible, in investigations of coprozoic and other Protozoa. -
Amoeba, Paramoecium, Euglena and Diatom
BIOLOGY CLASSIFICATION OF PLANTS Kingdom Protista Introduction to Kingdom Protista Kingdom Protista consists of unicellular organisms. They contain a well-defined nucleus and a nucleolus enclosed in a nuclear membrane. The protoplasm is surrounded by the plasma membrane. The cytoplasm contains various cell organelles. Nuclear material is organised in the form of a linear, double-stranded and helical DNA, along with proteins. The mode of nutrition is either autotrophic or heterotrophic. Examples: Amoeba, Paramoecium, Euglena and diatom Amoeba Paramoecium Euglena Diatom Amoeba Amoeba is microscopic and one of the simplest organisms made of just one cell. It is found in ponds, ditches, mud or on submerged water plants in freshwater bodies. The body of Amoeba is irregular in shape. The outer membrane called cell membrane or plasmalemma encloses the cytoplasm. A prominent nucleus, several food vacuoles, a contractile vacuole and reserve food granules are present. Amoeba uses pseudopodia for feeding and locomotion. It reproduces by binary fission. During unfavourable conditions (e.g. drying up of pond), it forms a protective cyst within which it reproduces by multiple fission, producing several offspring. Structure of Amoeba www.topperlearning.com 2 BIOLOGY CLASSIFICATION OF PLANTS Movement in Amoeba Movement in Amoeba occurs with the help of temporary or false feet called pseudopodia. Pseudopodia are finger-like projections formed by the flowing of cytoplasm into these extensions. At a time, several pseudopodia can be seen projecting out from the body of an Amoeba. However, only one of them extends longer than the others towards the direction it wants to move. This type of movement is called amoeboid movement. -
Protozoa : Locomotion and Nutrition
Protozoa : locomotion and Nutrition Lecturer : P. V. Deokar Department of Zoology R.K.M.M. Ahmednagar Locomotion in Protozoa • The following points highlight the three main types of locomotion exhibited by protozoans. The types of locomotion are: • 1. Amoeboid Movement • 2. Flagellar Movement • 3. Ciliary Movement. Protozoans: Type of Locomotion # 1. Amoeboid Movement: • movement of the animal is made by the throwing of pseudopodium, called amoeboid movement • In the direction of movement of Amoeba a new pseudopodium is formed and the pseudopodium at the opposite side gradually disappears. • Types of pseudopodia: • According to form, structure and activity four different kinds of pseudopodia are recognised • These are: • (a) Lobopodium • (b) Filopodium • (c) Reticulopodium or Rhizopodium • (d) Axopodium or Actinopodium (a) Lobopodium [Gk. lobes = lobe; podium = foot]: • It is a short, finger or tongue-like projection which is accompanied by a flow of endoplasm and ectoplasm. • The pseudopodium is broad with rounded or blunt tips. • The ectoplasmmic area is distinctly clear, called the hyaline cap. • It is the characteristic of many amoebas such as Amoeba. (b) Filopodium [L.filo = a thread; podium = foot]: • The filopodium is a slender, thread-like or filamentous projection. • It is formed by the ectoplasm alone and without a hyaline cap. • The filaments are narrow and may be branched but do not anastomose, Filopodium is the characteristic in Filosea (e.g., Euglypha ). (c) Reticulopodium or Rhizopodium [L. reticulos = a net, podium = foot]: • Similar in structure to that of filopodium but the branches anastomose. • The numerous branched and anastomosed pseudopodia form a dense network, help primarily in capturing the prey and the secondary function is locomotion. -
Brown Algae and 4) the Oomycetes (Water Molds)
Protista Classification Excavata The kingdom Protista (in the five kingdom system) contains mostly unicellular eukaryotes. This taxonomic grouping is polyphyletic and based only Alveolates on cellular structure and life styles not on any molecular evidence. Using molecular biology and detailed comparison of cell structure, scientists are now beginning to see evolutionary SAR Stramenopila history in the protists. The ongoing changes in the protest phylogeny are rapidly changing with each new piece of evidence. The following classification suggests 4 “supergroups” within the Rhizaria original Protista kingdom and the taxonomy is still being worked out. This lab is looking at one current hypothesis shown on the right. Some of the organisms are grouped together because Archaeplastida of very strong support and others are controversial. It is important to focus on the characteristics of each clade which explains why they are grouped together. This lab will only look at the groups that Amoebozoans were once included in the Protista kingdom and the other groups (higher plants, fungi, and animals) will be Unikonta examined in future labs. Opisthokonts Protista Classification Excavata Starting with the four “Supergroups”, we will divide the rest into different levels called clades. A Clade is defined as a group of Alveolates biological taxa (as species) that includes all descendants of one common ancestor. Too simplify this process, we have included a cladogram we will be using throughout the SAR Stramenopila course. We will divide or expand parts of the cladogram to emphasize evolutionary relationships. For the protists, we will divide Rhizaria the supergroups into smaller clades assigning them artificial numbers (clade1, clade2, clade3) to establish a grouping at a specific level. -
Evolutionary History Predicts the Stability of Cooperation in Microbial Communities
ARTICLE Received 13 Aug 2013 | Accepted 9 Sep 2013 | Published 11 Oct 2013 DOI: 10.1038/ncomms3573 Evolutionary history predicts the stability of cooperation in microbial communities Alexandre Jousset1,2, Nico Eisenhauer3, Eva Materne1 & Stefan Scheu1 Cooperation fundamentally contributes to the success of life on earth, but its persistence in diverse communities remains a riddle, as selfish phenotypes rapidly evolve and may spread until disrupting cooperation. Here we investigate how evolutionary history affects the emergence and spread of defectors in multispecies communities. We set up bacterial communities of varying diversity and phylogenetic relatedness and measure investment into cooperation (proteolytic activity) and their vulnerability to invasion by defectors. We show that evolutionary relationships predict the stability of cooperation: phylogenetically diverse communities are rapidly invaded by spontaneous signal-blind mutants (ignoring signals regulating cooperation), while cooperation is stable in closely related ones. Maintenance of cooperation is controlled by antagonism against defectors: cooperators inhibit phylogenetically related defectors, but not distant ones. This kin-dependent inhibition links phylogenetic diversity and evolutionary dynamics and thus provides a robust mechanistic predictor for the persistence of cooperation in natural communities. 1 J.F. Blumenbach Institute of Zoology and Anthropology, Georg August University Go¨ttingen, Berliner Strae 28, 37073 Go¨ttingen, Germany. 2 Department of Ecology and Biodiversity, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands. 3 Institute of Ecology, Friedrich-Schiller-University Jena, Dornburger Str. 159, 07743 Jena, Germany. Correspondence and requests for materials should be addressed to A.J. (email: [email protected]). NATURE COMMUNICATIONS | 4:2573 | DOI: 10.1038/ncomms3573 | www.nature.com/naturecommunications 1 & 2013 Macmillan Publishers Limited. -
The Pseudopodia of the Leucocytes of Invertebrates
PSEUDOPODIA OF THE LEUCOCYTES OF INA^EBTDBEATES. 19 The Pseudopodia of the Leucocytes of Invertebrates. By Edwin S. Ooodricli, F.R.S., Fellow of Merton College, Oxford. With Plates 1 and 2. IT is to Wharton Jones that we owe the first comprehensive account of the leucocytes in the various groups of Inverte- brata: in an important paper, published in 1846 (6), he described and figured them as of "stellate appearance/' and sometimes as shooting out "cilia-like processes." Since then numberless authors have studied these cells and pictured them as provided with free outstanding pseudopodia. Evidence is brought forward in this paper that the spiny appearance of leucocytes is of the nature of an optical illusion or due to changes taking place under abnormal conditions, that freely projecting fine processes are seldom, if ever, produced in the fluids of living invertebrates, and that the pointed pseudo- podia so often figured are merely the optical sections of deliciite, more or less folded films. Various authors have from time to time mentioned the flattened expanded shape of the processes of the leucocytes of the inv- rtebrates, as, for instance, Cattaneo (1) and Dek- hiu'M'ii (2), referred to below ; but none seem to have realised thai i his is ihe normal shape of the pseudopodia. In 1898 (4) I drew attention to the presence of membranous expansions of the lriicocytes in the Polychaste worm G-lycera, ahd at that tim<" observed the same structures in other invertebrates; but 20 EDWIN S. GOODRICH. other work prevented my pursuing the subject, and it was not till last winter that it was again taken up, when I had the opportunity of confirming and extending my observations at the Marine Biological Laboratory in Plymouth.