scholarly journals Molecular Characterization of the Myoliquefactive Fish Parasite Kudoa mirabilis (Cnidaria, Kudoidae) from SW Indian Ocean and Its Phylogenetic Relationship with the Kudoa thyrsites Species Complex

2020 ◽  
Vol 8 (9) ◽  
pp. 1352
Author(s):  
Lucilla Giulietti ◽  
Egil Karlsbakk ◽  
Paolo Cipriani ◽  
Salome Daniel Shayo ◽  
Julia E. Storesund ◽  
...  

Myxosporean parasites of the genus Kudoa are fish parasites of great economic importance, as some species can affect the fish fillet quality by producing macroscopic cysts or generating post mortem myoliquefaction, commonly referred to as ‘soft flesh’. Kudoa mirabilis is a ‘soft flesh’-inducing species originally described based on morphology in the musculature of Trichiurus lepturus from the Indian Ocean. An integrative morphological and genetic characterization of K. mirabilis from the type host caught off the coast of Tanzania is here provided. The spores were stellate with four unequal polar capsules, showing similarities to Kudoa thyrsites. For comparative and validation purpose, K. mirabilis was compared morphologically and genetically with K. thyrsites reference isolates, including new obtained samples from the type host Thyrsites atun caught in the SE Atlantic Ocean. Morphological analyses of spores revealed key diagnostic characters clearly distinguishing the two Kudoa species. Phylogenetic analyses based on SSU and LSU rRNA genes demonstrated that K. mirabilis is a distinct and valid species, representing a sister group to a K. thyrsites subclade that comprises several isolates from Japan and one single isolate from South Africa. This finding raises questions about the true diversity likely hidden in the K. thyrsites complex.

Nematology ◽  
2015 ◽  
Vol 17 (9) ◽  
pp. 1045-1056 ◽  
Author(s):  
Razieh Ghaemi ◽  
Ebrahim Pourjam ◽  
Sergio Álvarez-Ortega ◽  
Majid Pedram ◽  
Mohammad Reza Atighi

Diploscapteroides persicus n. sp. is described and illustrated based on morphological, morphometric and molecular data. The new species is mainly characterised by female body length of 469-673 μm, female tail length of 51-99 μm, shape of gubernaculum and spicules and arrangement of male genital papillae. Also, the arrangement of male genital papillae of the new species shows the presence of precloacal papillae, a feature that has not been previously described for the genus. The new species is comparable with all valid species of the genus, namely D. boettgeri, D. brevicauda, D. chitinolabiatus, D. coroniger, D. dacchensis and D. flexuosus, from which the morphological comparisons of the new species with aforementioned species are discussed. Phylogenetic analyses using partial sequences of SSU and LSU rRNA genes were performed for the new species, being the first representative of the genus to be phylogenetically studied using both Bayesian inference (BI) and maximum likelihood (ML) methods, and revealed that D. persicus n. sp. formed a clade with a species of Cephaloboides.


Zootaxa ◽  
2021 ◽  
Vol 4952 (3) ◽  
pp. 465-494
Author(s):  
SHO TSUKAMOTO ◽  
SHIMPEI F. HIRUTA ◽  
KATSUYUKI EGUCHI ◽  
JHIH-RONG LIAO ◽  
SATOSHI SHIMANO

In Japan and Taiwan, five valid species of the genus Scolopendra Linnaeus, 1758 have been described: S. morsitans Linnaeus, 1758, S. subspinipes Leach, 1816, S. mutilans Koch, 1878, S. japonica Koch, 1878, and S. multidens Newport, 1844. Recently, an undetermined species was found in the Ryukyu Archipelago and Taiwan. Using molecular phylogenetic analyses with mitochondrial COI and 16S rRNA and nuclear 28S rRNA and 18S rRNA genes as well as conventional morphological examination, we successfully discriminated this sixth species as an independent lineage from S. subspinipes, S. mutilans, and other named congeners from East and Southeast Asia. Therefore, the species was described as S. alcyona Tsukamoto & Shimano, sp. nov. Several situational evidences suggest that this species prefers streamside environments and exhibits amphibious behavior. 


2008 ◽  
Vol 74 (12) ◽  
pp. 3899-3907 ◽  
Author(s):  
Monica O. Mendez ◽  
Julia W. Neilson ◽  
Raina M. Maier

ABSTRACT Bacterial diversity in mine tailing microbial communities has not been thoroughly investigated despite the correlations that have been observed between the relative microbial diversity and the success of revegetation efforts at tailing sites. This study employed phylogenetic analyses of 16S rRNA genes to compare the bacterial communities present in highly disturbed, extremely (pH 2.7) and moderately (pH 5.7) acidic lead-zinc mine tailing samples from a semiarid environment with those from a vegetated off-site (OS) control sample (pH 8). Phylotype richness in these communities decreased from 42 in the OS control to 24 in the moderately acidic samples and 8 in the extremely acidic tailing samples. The clones in the extremely acidic tailing sample were most closely related to acidophiles, none of which were detected in the OS control sample. The comparison generated by this study between the bacteria present in extremely acidic tailing and that in moderately acidic tailing communities with those in an OS control soil provides a reference point from which to evaluate the successful restoration of mine tailing disposal sites by phytostabilization.


Insects ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 338
Author(s):  
Yan Jiang ◽  
Hao-Xi Li ◽  
Xiao-Fei Yu ◽  
Mao-Fa Yang

The complete mitochondrial genomes of Atkinsoniella grahami and Atkinsoniella xanthonota were sequenced. The results showed that the mitogenomes of these two species are 15,621 and 15,895 bp in length, with A+T contents of 78.6% and 78.4%, respectively. Both mitogenomes contain 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs), 2 ribosomal RNA genes (rRNAs), and a control region (CR). For all PCGs, a standard start ATN codon (ATT, ATG, or ATA) was found at the initiation site, except for ATP8, for which translation is initiated with a TTG codon. All PCGs terminate with a complete TAA or TAG stop codon, except for COX2, which terminates with an incomplete stop codon T. All tRNAs have the typical cloverleaf secondary structure, except for trnS, which has a reduced dihydrouridine arm. Furthermore, these phylogenetic analyses were reconstructed based on 13 PCGs and two rRNA genes of 73 mitochondrial genome sequences, with both the maximum likelihood (ML) and Bayesian inference (BI) methods. The obtained mitogenome sequences in this study will promote research into the classification, population genetics, and evolution of Cicadellinae insects in the future.


2021 ◽  
Vol 755 ◽  
Author(s):  
Didier VandenSpiegel ◽  
Arnaud Henrard ◽  
Aurore Mathys

A new millipede species of the genus Sechelleptus Mauriès, 1980 is described and illustrated from Mayotte Island, Indian Ocean. This new species, S. arborivagus sp. nov., found on trees, looks particularly similar to the sympatric S. variabilis VandenSpiegel & Golovatch, 2007, but is much larger and has a very different ecological behavior. Phylogenetic analyses based on a concatenated dataset of the COI and 16S rRNA genes and including nine species of Spirostreptidae (including Sechelleptus, Doratogonus Attems, 1914, Bicoxidens Attems, 1928 and Spirostreptus Brandt, 1833), strongly support the monophyly of Sechelleptus. Despite the similarity of their genitalia, the molecular analyses also reveal a clear-cut genetic divergence between S. arborivagus sp. nov. and S. variabilis (22.55% for COI and 6.63% for 16SrRNA) and further suggest the presence of a higher diversity within the genus Sechelleptus on Mayotte.


2015 ◽  
Vol 97 (1) ◽  
pp. 234-245 ◽  
Author(s):  
Pascuala Ambriz-Morales ◽  
Xochitl F. De La Rosa-Reyna ◽  
Ana Maria Sifuentes-Rincon ◽  
G. Manuel Parra-Bracamonte ◽  
Abraham Villa-Melchor ◽  
...  

Abstract The white-tailed deer ( Odocoileus virginianus ) is an important, sustainable-use species in Mexico; 14 subspecies are widely distributed throughout the Mexican territory. The criteria for classifying subspecies is based on morphological features throughout their geographical range; however, the complete genetic characterization of Mexican subspecies has not been established. The objective of the present work is to report the mitogenomes of 9 of the 14 white-tailed deer subspecies from Mexico and identify their unique variations. Typical vertebrate mitogenomes structures (i.e., 13 protein-coding genes, 22 tRNA genes, and 2 rRNA genes) were observed in the studied subspecies. The greatest numbers of polymorphisms were identified in the D-loop, ND4, ND5, CYTB/COI, ATP6, and COIII genes. Phylogenetic analyses showed that the southern and southeastern subspecies were distinct from the central and northern subspecies; the greatest genetic distances were also observed between these 2 groups. These subspecies-specific variations could be useful for designing a strategy to genetically characterize the studied subspecies. El venado cola blanca es una de las especies de mayor importancia dentro del aprovechamiento de la fauna silvestre de México, donde se distribuyen de manera natural 14 subespecies. Actualmente, estas subespecies se han clasificado de acuerdo a sus variaciones fenotípicas que presentan a lo largo de su rango de distribución, sin embargo no se ha establecido la caracterización genética completa de las mismas. Es por esto que el objetivo del presente estudio es reportar los mitogenomas de 9 de las 14 subespecies de venado cola blanca, así como identificar las variaciones únicas de cada subespecie. En las 9 subespecies se observó la estructura típica de los mitogenomas de vertebrados (13 genes que codifican para proteínas, 22 ARNt, 2 ARNr). Los genes con mayor polimorfismo fueron D-loop, ND4, ND5, CYTB/COI, ATP6 y COIII. El análisis filogenético mostró la separación de las subespecies del sur y sureste de las subespecies del centro y norte del país, a su vez las distancias genéticas entre estos dos grupos fueron las más altas. Estas variaciones subespecie-específicas podrían ser útiles para diseñar una estrategia para caracterizar genéticamente las subespecies estudiadas.


Nematology ◽  
2010 ◽  
Vol 12 (3) ◽  
pp. 429-451 ◽  
Author(s):  
Juan Navas-Cortés ◽  
Blanca Landa ◽  
Nicola Vovlas ◽  
Gracia Liébanas ◽  
Pablo Castillo ◽  
...  

AbstractA new amphimictic species, Pratylenchus hispaniensis n. sp., parasitising the roots of gum cistus in Andújar (Jaén), southern Spain, is described. The new species is characterised by the presence of numerous males and by the female having a lip region with three annuli, a divided face, a robust stylet (14.5-17.0 μm) with rounded knobs, lateral fields with four lines, V = 80-84, a round spermatheca full of sperm, well developed post-vulval uterine sac and an obliquely truncate tail with irregularly annulated terminus. Morphologically this species is related to P. bhatti, P. kralli, P. mediterraneus, P. pseudofallax and P. thornei. A phenetic study of the 25 most useful diagnostic morphological and allometric characters for Pratylenchus species was done using multivariate factor and linear discriminant analyses. In the factor analysis the first seven factors accounted for 71.1% of the total variance of the characters selected. These factors were related to female tail, pharyngeal overlap, reproductive behaviour, stylet length, L/post-vulval uterine sac ratio, body length and number of lip annuli. Discriminant analysis differentiated Pratylenchus spp. from the three valid species of Zygotylenchus. The results of the phylogenetic analysis based on sequences of the D2-D3 expansion regions of 28S, partial 18S and ITS rRNA genes confirmed the close relationship of P. hispaniensis n. sp. with P. mediterraneus and inferred molecular affinity with P. brzeskii, P. neglectus and P. thornei, in spite of variation in the position of P. hispaniensis n. sp. in the clades. Additional phylogenetic analyses based on the same sets of sequences for P. hispaniensis n. sp., Zygotylenchus guevarai and other Pratylenchidae indicated that Pratylenchus includes several paraphyletic lineages; however, likelihood tests did not reject monophyly of the genus. The inclusion of Pratylenchus, Zygotylenchus, Hirschmanniella, Nacobbus and Apratylenchus in Pratylenchidae was supported.


2018 ◽  
Vol 16 (2) ◽  
pp. 219-226
Author(s):  
Sri Rizqi Annisa ◽  
Dewi Larasati ◽  
Endang Bekti K

The aim of this study was to determine the characterization of shredded mureel fish with kluwih substitution on water content, protein content, fiber content and organoleptic (preference for crispness and taste). This study uses a simple Randomized Complete Design (RCD) with the substitution treatment of kluwih and mureel fish, with the following ratio: S1 (240g: 60g), S2 (210g: 90g), S3 (180g: 120g), S4 (150g: 150g), S5 (120g: 180g). Data were analyzed statistically by analysis of variance and if there was a significant effect, further testing was done with BNJ at the level of 5%. The results showed that kluwih substitution in the manufacture of mureel fish shredded had an average: water content of 8.33-10.62%, protein :16.83-22.00%, fiber : 6.79-6.99%, score crispness 2-6.12, taste score 2.6-6.6. Based on the results of the analysis of the variety of kluwih substitutes and mureel fish have a significant effect on water content, protein content and crisp organoleptic test, taste on mureel fish fillet, and no significant effect on fiber content. The best kluwih substitution in S3 treatment with 120 grams of substitute kluwih and 180 grams of mureel fish.


Parasitology ◽  
1999 ◽  
Vol 118 (6) ◽  
pp. 541-551 ◽  
Author(s):  
N. E. COLLINS ◽  
B. A. ALLSOPP

We sequenced the rRNA genes and internal transcribed spacers (ITS) of several Theileria parva isolates in an attempt to distinguish between the causative agents of East coast fever and Corridor disease. The small subunit (SSU) and large subunit (LSU) rRNA genes from a cloned T. p. lawrencei parasite were sequenced; the former was identical to that of T. p. parva Muguga, and there were minor heterogeneities in the latter. The 5·8S gene sequences of 11 T. parva isolates were identical, but major differences were found in the ITS. Six characterization oligonucleotides were designed to hybridize within the variable ITS1 region; 93·5% of T. p. parva isolates examined were detected by probe TPP1 and 81·8% of T. p. lawrencei isolates were detected by TPL2 and/or TPL3a. There was no absolute distinction between T. p. parva and T. p. lawrencei and the former hybridized with fewer of the probes than did the latter. It therefore seems that a relatively homogenous subpopulation of T. parva has been selected in cattle from a more diverse gene pool in buffalo. The ITSs of both T. p. parva and T. p. lawrencei contained different combinations of identifiable sequence segments, resulting in a mosaic of segments in any one isolate, suggesting that the two populations undergo genetic recombination and that their gene pools are not completely separate.


2021 ◽  
Vol 9 (4) ◽  
pp. 749
Author(s):  
Gülbahar Abaramak ◽  
Jaime Ricardo Porras-Domínguez ◽  
Henry Christopher Janse van Rensburg ◽  
Eveline Lescrinier ◽  
Ebru Toksoy Öner ◽  
...  

Fructans are fructose-based (poly)saccharides with inulin and levan being the best-known ones. Thanks to their health-related benefits, inulin-type fructans have been under the focus of scientific and industrial communities, though mostly represented by plant-based inulins, and rarely by microbial ones. Recently, it was discovered that some extremely halophilic Archaea are also able to synthesize fructans. Here, we describe the first in-depth functional and molecular characterization of an Archaeal inulosucrase from Halomicrobium sp. IBSBa (HmcIsc). The HmcIsc enzyme was recombinantly expressed and purified in Escherichia coli and shown to synthesize inulin as proven by nuclear magnetic resonance (NMR) analysis. In accordance with the halophilic lifestyle of its native host, the enzyme showed maximum activity at very high NaCl concentrations (3.5 M), with specific adaptations for that purpose. Phylogenetic analyses suggested that Archaeal inulosucrases have been acquired from halophilic bacilli through horizontal gene transfer, with a HX(H/F)T motif evolving further into a HXHT motif, together with a unique D residue creating the onset of a specific alternative acceptor binding groove. This work uncovers a novel area in fructan research, highlighting unexplored aspects of life in hypersaline habitats, and raising questions about the general physiological relevance of inulosucrases and their products in nature.


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