The first data on species diversity of leeches (Hirudinea) in the Irtysh River Basin, East Kazakhstan

Kaygorodova, Irina A., Fedorova, Lyudmila I. (2016): The first data on species diversity of leeches (Hirudinea) in the Irtysh River Basin, East Kazakhstan. Zootaxa 4144 (2): 287-290, DOI: http://doi.org/10.11646/zootaxa.4144.2.1

Erpobdella vilnensis Liskiewicz 1925

Species: <i>Erpobdella vilnensis</i> (Liskiewicz, 1925) <p> <b>Geographic distribution.</b> Palaearctic species. It is known from central to east Europe, widespread throughout Poland, Austria, Czechia, Slovakia, Hungary, Romania, Slovenia and Latvia (Nesemann & Neubert 1999). The easternmost distribution records were from Kyrgyzstan (Jueg <i>et al.</i> 2013), until it was discovered in the East Kazakhstan, in this study.</p> <p>Irtysh River area: The Irtysh River (N52º19′17′′ / E76º53′22′′), the Peschanka River (N50º10′08′′ / E82º03′ 07'′), the Kyzylsu River (N50º06′ 14′/ E81º32′ 56'′), the Shulbinsk water reservoir (N50º22′53′′ / E81º06′13′′; N50º23′35′′ / E81º05′36′′), and the Bukhtarma water reservoir (N49º36′58′′ / E83º31′33′′; N49º37′01′′ / E83º34′18′′; N49º37′39′′ / E83º27′21′′), Lake Bolshoe (N50º43′16′′ / E79º40′49′′), and Lake Maloe (N50º43′45′′ / E79º40′15′′).</p> <p> <b>Ecology.</b> The preferred habitats were rocky substrates in the shallow zone of the water reservoirs. This is the most common erpobdellid species in mountain streams.</p> <p> <b>FAMILY: HAEMOPIDAE Richardson, 1969</b></p> <p> <b> Species: <i>Haemopis sanguisuga</i> (Linnaeus, 1758)</b> </p> <p> <b>Geographic distribution.</b> Palaearctic region.</p> <p> Irtysh River area: The Irtysh River (N52º16′52′′ / E76º56′06′′; N50º25′26′′ / E80º12′34′′). <b>Ecology.</b> This species was found in river floodplain. The horse-leech is a predator of aquatic and terrestrial</p> <p>invertebrates, with earthworms and mollusks as a basis of its feeding.</p> <p> <b>FAMILY: PRAOBDELLIDAE Blanchard, 1894</b></p> <p> <b> Species: <i>Limnatis paluda</i> (Tennent, 1859)</b> </p> <p> Synonymy: <i>Haemopis paludum</i>: Tennant, 1859; <i>Limnatis paluda</i>: Moore, 1927. <b>Geographic distribution.</b> India and Sri Lanka (Nesemann & Neubert 1999), Southeastern Kazakhstan (Nakano <i>et al.</i> 2015).</p> <p>Irtysh River area: Lake Bolshoe (N50º43′16′′ / E79º40′49′′).</p> <p> <b>Ecology.</b> <i>Limnatis paluda</i> is a temporal ectoparasite that lives only in shallow part of standing water bodies. This leech was first described from Sri Lanka and was stated to be a cattle leech there. Now it known as a parasite of humans and other large mammals.</p>Published as part of <i>Kaygorodova, Irina A. & Fedorova, Lyudmila I., 2016, The first data on species diversity of leeches (Hirudinea) in the Irtysh River Basin, East Kazakhstan, pp. 287-290 in Zootaxa 4144 (2)</i> on pages 289-290, DOI: 10.11646/zootaxa.4144.2.10, <a href="http://zenodo.org/record/260946">http://zenodo.org/record/260946</a&gt

Investigation of NO Role in Neural Tissue in Brain and Spinal Cord Injury

Nitric oxide (NO) production in injured and intact brain regions was compared by EPR spectroscopy in a model of brain and spinal cord injury in Wistar rats. The precentral gyrus of the brain was injured, followed by the spinal cord at the level of the first lumbar vertebra. Seven days after brain injury, a reduction in NO content of 84% in injured brain regions and 66% in intact brain regions was found. The difference in NO production in injured and uninjured brain regions persisted 7 days after injury. The copper content in the brain remained unchanged one week after modeling of brain and spinal cord injury. The data obtained in the experiments help to explain the problems in the therapy of patients with combined brain injury

The Cytoplasmic Tail of Influenza A Virus Hemagglutinin and Membrane Lipid Composition Change the Mode of M1 Protein Association with the Lipid Bilayer

Influenza A virus envelope contains lipid molecules of the host cell and three integral viral proteins: major hemagglutinin, neuraminidase, and minor M2 protein. Membrane-associated M1 matrix protein is thought to interact with the lipid bilayer and cytoplasmic domains of integral viral proteins to form infectious virus progeny. We used small-angle X-ray scattering (SAXS) and complementary techniques to analyze the interactions of different components of the viral envelope with M1 matrix protein. Small unilamellar liposomes composed of various mixtures of synthetic or “native” lipids extracted from Influenza A/Puerto Rico/8/34 (H1N1) virions as well as proteoliposomes built from the viral lipids and anchored peptides of integral viral proteins (mainly, hemagglutinin) were incubated with isolated M1 and measured using SAXS. The results imply that M1 interaction with phosphatidylserine leads to condensation of the lipid in the protein-contacting monolayer, thus resulting in formation of lipid tubules. This effect vanishes in the presence of the liquid-ordered (raft-forming) constituents (sphingomyelin and cholesterol) regardless of their proportion in the lipid bilayer. We also detected a specific role of the hemagglutinin anchoring peptides in ordering of viral lipid membrane into the raft-like one. These peptides stimulate the oligomerization of M1 on the membrane to form a viral scaffold for subsequent budding of the virion from the plasma membrane of the infected cell

Structural Analysis of Influenza A Virus Matrix Protein M1 and Its Self-Assemblies at Low pH

<div><p>Influenza A virus matrix protein M1 is one of the most important and abundant proteins in the virus particles broadly involved in essential processes of the viral life cycle. The absence of high-resolution data on the full-length M1 makes the structural investigation of the intact protein particularly important. We employed synchrotron small-angle X-ray scattering (SAXS), analytical ultracentrifugation and atomic force microscopy (AFM) to study the structure of M1 at acidic pH. The low-resolution structural models built from the SAXS data reveal a structurally anisotropic M1 molecule consisting of a compact NM-fragment and an extended and partially flexible C-terminal domain. The M1 monomers co-exist in solution with a small fraction of large clusters that have a layered architecture similar to that observed in the authentic influenza virions. AFM analysis on a lipid-like negatively charged surface reveals that M1 forms ordered stripes correlating well with the clusters observed by SAXS. The free NM-domain is monomeric in acidic solution with the overall structure similar to that observed in previously determined crystal structures. The NM-domain does not spontaneously self assemble supporting the key role of the C-terminus of M1 in the formation of supramolecular structures. Our results suggest that the flexibility of the C-terminus is an essential feature, which may be responsible for the multi-functionality of the entire protein. In particular, this flexibility could allow M1 to structurally organise the viral membrane to maintain the integrity and the shape of the intact influenza virus.</p></div

AFM topography image of M1 protein structures formed at negatively charged surface.

<p>The inset displays a magnification of the region outlined by white frame.</p

Flexibility of the C-terminal of M1 analysed by EOM.

<p>Left panel: experimental SAXS data (1) and the scattering from the selected ensemble. Middle and right panels: <i>R_g</i> and <i>D_max</i> distributions, respectively (random pool (1), selected ensemble (2)).</p

Experimental SAXS patterns from the full length M1 protein (left panel) and the NM-domain (right panel).

<p>The individual curves correspond to the varying solute concentrations; for M1, curves 1 to 4 represent c =  4.5 mg/ml; 3.4 mg/ml, 2.3 mg/ml and 1.7 mg/ml, respectively; for NM-domain, curves 1 to 3 represent c = 3.8 mg/ml, 3.0 mg/ml and 1.5 mg/ml, respectively.</p

The <i>R_g</i> and <i>D_max</i> computed from the solution of the full length M1 protein as a function of the cut-off value at small angles <i>s_min</i>.

<p>The <i>R_g</i> and <i>D_max</i> computed from the solution of the full length M1 protein as a function of the cut-off value at small angles <i>s_min</i>.</p

Shape restoration of the NM-domain.

<p>Left panel: experimental SAXS data (1), the transformed from <i>p(r)</i> and extrapolated to zero scattering angle intensity (2), scattering pattern computed from the GASBOR model (3). Insert: distance distribution function <i>p(r)</i> computed by GNOM. Right panel: the model reconstructed by GASBOR (red balls, dummy residues, green balls: dummy water molecules) (a), crystal structure of the NM-domain (PDB code 1AA7) (b).</p