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1.
Int J Mol Sci ; 25(9)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38732132

RESUMO

Insects possess an effective immune system, which has been extensively characterized in several model species, revealing a plethora of conserved genes involved in recognition, signaling, and responses to pathogens and parasites. However, some taxonomic groups, characterized by peculiar trophic niches, such as plant-sap feeders, which are often important pests of crops and forestry ecosystems, have been largely overlooked regarding their immune gene repertoire. Here we annotated the immune genes of soft scale insects (Hemiptera: Coccidae) for which omics data are publicly available. By using immune genes of aphids and Drosophila to query the genome of Ericerus pela, as well as the transcriptomes of Ceroplastes cirripediformis and Coccus sp., we highlight the lack of peptidoglycan recognition proteins, galectins, thaumatins, and antimicrobial peptides in Coccidae. This work contributes to expanding our knowledge about the evolutionary trajectories of immune genes and offers a list of promising candidates for developing new control strategies based on the suppression of pests' immunity through RNAi technologies.


Assuntos
Hemípteros , Proteínas de Insetos , Animais , Hemípteros/genética , Hemípteros/imunologia , Proteínas de Insetos/genética , Proteínas de Insetos/imunologia , Transcriptoma/genética , Filogenia , Peptídeos Antimicrobianos/genética , Galectinas/genética , Galectinas/metabolismo , Proteínas de Transporte
2.
Proc Natl Acad Sci U S A ; 117(49): 31398-31409, 2020 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-33229580

RESUMO

Toxin-antitoxin systems are found in many bacterial chromosomes and plasmids with roles ranging from plasmid stabilization to biofilm formation and persistence. In these systems, the expression/activity of the toxin is counteracted by an antitoxin, which, in type I systems, is an antisense RNA. While the regulatory mechanisms of these systems are mostly well defined, the toxins' biological activity and expression conditions are less understood. Here, these questions were investigated for a type I toxin-antitoxin system (AapA1-IsoA1) expressed from the chromosome of the human pathogen Helicobacter pylori We show that expression of the AapA1 toxin in H. pylori causes growth arrest associated with rapid morphological transformation from spiral-shaped bacteria to round coccoid cells. Coccoids are observed in patients and during in vitro growth as a response to different stress conditions. The AapA1 toxin, first molecular effector of coccoids to be identified, targets H. pylori inner membrane without disrupting it, as visualized by cryoelectron microscopy. The peptidoglycan composition of coccoids is modified with respect to spiral bacteria. No major changes in membrane potential or adenosine 5'-triphosphate (ATP) concentration result from AapA1 expression, suggesting coccoid viability. Single-cell live microscopy tracking the shape conversion suggests a possible association of this process with cell elongation/division interference. Oxidative stress induces coccoid formation and is associated with repression of the antitoxin promoter and enhanced processing of its transcript, leading to an imbalance in favor of AapA1 toxin expression. Our data support the hypothesis of viable coccoids with characteristics of dormant bacteria that might be important in H. pylori infections refractory to treatment.


Assuntos
Helicobacter pylori/citologia , Helicobacter pylori/efeitos dos fármacos , Peptídeos/farmacologia , Sistemas Toxina-Antitoxina , Trifosfato de Adenosina/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Helicobacter pylori/ultraestrutura , Peróxido de Hidrogênio/toxicidade , Espaço Intracelular/metabolismo , Cinética , Potenciais da Membrana/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Peptidoglicano/metabolismo
3.
Microorganisms ; 12(5)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38792698

RESUMO

Coccoid Ulvophyceae are often overlooked despite their wide distribution. They occur as epiphytes on marine seaweeds or grow on stones or on shells of mussels and corals. Most of the species are not easy to identify based solely on morphology. However, they form two groups based on the flagellated cells during asexual reproduction. The biflagellated coccoids are monophyletic and represent the genus Sykidion (Sykidiales). In contrast, the quadriflagellated taxa are polyphyletic and belong to different genera and orders. The newly investigated strains NIES-1838 and NIES-1839, originally identified as Halochlorococcum, belong to the genus Chlorocystis (C. john-westii) among the order Chlorocystidales. The unidentified strain CCMP 1293 had almost an identical SSU and ITS-2 sequence to Symbiochlorum hainanense (Ignatiales) but showed morphological differences (single chloroplast, quadriflagellated zoospores) compared with the original description of this species (multiple chloroplasts, aplanospores). Surprisingly, the strain SAG 2662 (= ULVO-129), together with the published sequence of MBIC 10461, formed a new monophyletic lineage among the Ulvophyceae, which is highly supported in all of the bootstrap and Bayesian analyses and approximately unbiased tests of user-defined trees. This strain is characterized by a spherical morphology and also form quadriflagellated zoospores, have a unique ITS-2 barcode, and can tolerate a high variation of salinities. Considering our results, we emend the diagnosis of Symbiochlorum and propose the new genus Solotvynia among the new order Solotvyniales.

4.
Insects ; 13(11)2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36354823

RESUMO

In this study, a new species of mealybug from the Cape Verde Islands, Mirococcus capeverdensis Lagowska and Hodgson sp. n., collected on Campylanthus glaber Benth. (Scrophulariaceae), a native plant to these islands, is described and illustrated based on the adult female. A taxonomic key to the mealybugs from the Afrotropical Region that lack cerarii is provided. In addition, seven scale insect species, namely Aulacaspis tubercularis Newstead, Hemiberlesia cyanophylli (Signoret), Pseudaonidia trilobitiformis (Green), Icerya aegyptiaca (Douglas), Maconellicoccus hirsutus (Green), Palmicultor palmarum (Ehrhorn), and Pseudococcus comstocki (Kuwana) are recorded for the first time from the Cape Verde Islands and an updated checklist of Coccomorpha species known from this region, along with their known island distributions and valid sources, is appended.

5.
Zookeys ; 1136: 163-174, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36762051

RESUMO

The venation of the fore wings of male scale insects is strongly reduced and the nomenclature used for each vein is inconsistent among taxonomists. This paper reviews the different nomenclatural systems in the wing venation of male scale insects that have been suggested previously and puts forward a new system based mainly on newly found wing venation in males of Qinococcuspodocarpus Wu, 2022 (Hemiptera: Coccomorpha: Qinococcidae).

6.
Recent Adv Antiinfect Drug Discov ; 17(3): 199-211, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36056835

RESUMO

BACKGROUND: Helicobacter pylori eradication therapy can be considered effective if the result of its implementation is removed including all roots and rootlets from which surviving H. pylori can repopulate in the gastric mucosa. One of the reasons for the ineffectiveness of eradication therapy can be the continuous presence of viable coccoid forms of H. pylori in the oral cavity. Therefore, anti-Helicobacter eradication therapy should be supplemented by the sanitation of the oral cavity. OBJECTIVES: The objective of this study is to determine the frequency of occurrence of H. pylori in the gastric mucosa and in the oral cavity in patients with chronic periodontitis or with chronic gastritis using immunocytochemical method and to evaluate the pathophysiological relationship between periodontitis and HP-associated acid-dependent stomach diseases mediated by H. pylori. METHODS: A group of patients with chronic gastritis (70 participants, 46 women, 24 men, age: 24 - 55 years) and another group with chronic periodontitis before the start of surgical treatment (61 participants, 30 women, 31 men, age: 20 - 60 years) were examined for НР bacterial cells using immunocytochemical methods of staining gastric biopsy and exfoliate samples from the gingival sulcus surface. The participants did not take any antimicrobial medication before and during the examination. Routine staining was also performed to view microbiota in smears for both groups. The participants signed a voluntary consent agreement to undergo routine medical examinations and join the study at the Nikiforov Russian Centre of Emergency and Radiation Medicine, EMERCOM of Russia, where the ethical committee was made. RESULTS: Immunocytochemical method could identify all stages of bacillary-coccoid transformation of H. pylori which accounted for 63.4-67.5% of cases. HP-antigenpositive bacteria were found in the oral cavity in both groups of examined patients. It was apparent that spiral forms of H. pylori were dominant over coccoid forms in the gastric mucosa in the antrum of the stomach, whereas coccoid forms of H. pylori were frequently found more in the oral cavity. Helicobacteriosis in the oral cavity was identified in chronic periodontitis. CONCLUSION: We found certain pathogenetic connections between inflammatory lesions of the oral cavity and diseases of the internal organs of the gastrointestinal tract. Accordingly, we suggest the necessity to use proper medication for oral cavity sanitation along with anti-Helicobacter eradication therapy to influence the HP reservoir in the oral cavity and gingival sulcus. Additionally, bacterial cells of HP reside in the oral cavity in coccoid forms; therefore, the coccoid form of HP should become the second principal target in treating HP.


Assuntos
Periodontite Crônica , Gastrite Atrófica , Infecções por Helicobacter , Helicobacter pylori , Masculino , Humanos , Feminino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Infecções por Helicobacter/tratamento farmacológico
7.
Zookeys ; 918: 65-81, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32210665

RESUMO

A checklist of scale insects recorded to date in Poland is presented. The data provided here are based on literature records and include the latest taxonomic and nomenclatural changes and updates on Coccomorpha reported in Poland. Changes in comparison with ScaleNet and Fauna Europaea electronic databases are also discussed. A total of 185 species belonging to 98 genera and 16 families are included in the list. Of this group, 47 species are alien introduced species and live only indoors, and one species, Pulvinaria floccifera (Westwood), develops both indoors and outdoors.

8.
Zookeys ; (747): 101-114, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29674906

RESUMO

Wings of Orthezia urticae males were studied. Both ventral and dorsal surfaces of wings were examined under light and scanning electron microscopes. The structure regarded as vein cubitus anterior turned out to be a reinforcement element only. Two elements known as radius sector and media are almost transparent depressions in the wing membrane. Veins at the margin of the fold of the wing anal lobe were not confirmed. Studies indicated a row of sensilla cupola at the beginning of the subcostal ridge. Cross sections of the wing membrane showed a two-layered membrane. The presence of two veins was confirmed in a common stem - subcostal and radius. The change of common stem shape was described. Neither tracheae nor nerves were observed. This is the second paper on cross-sections of wing within Sternorrhyncha.

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