15 research outputs found
Polymerase chain reaction and restriction fragment length polymorphism analysis of the ITS2 region for differatiation of Brazilian Biomphalaria intermediate hosts of the Schistosoma mansoni
Suscetibilidade de planorbídeos da região metropolitana de Belo Horizonte, MG (Brasil) ao Angiostrongylus costaricensis (Nematoda, Angiostrongylidae
Potential ecological distribution of alien mollusk Corbicula largillierti and its relationship with human disturbance in a semi-arid reservoir
Further Studies on the Molecular Systematics of Biomphalaria Snails from Brazil
The polymerase chain reaction and restriction fragment length
polymorphism (RFLP) of the internal transcribed spacer (ITS) region of
the rRNA gene, using the enzyme DdeI were used for the molecular
identification of ten species and one subspecies of Brazilian
Biomphalaria. Emphasis is given to the analysis of B. oligoza, B.
schrammi and B. amazonica. The RFLP profiles obtained using this enzyme
were highly distinctive for the majority of the species and exhibited
low levels of intraspecific polymorphism among specimens from different
regions of Brazil. However, B. peregrina and B. oligoza presented very
similar profiles that complicated their identification at the molecular
level and suggested a very close genetic similarity between the two
species. Others enzymes including HaeIII, HpaII, AluI and MnlI were
tested for their ability to differentiate these species. For B.
amazonica three variant profiles produced with DdeI were observed. The
study demonstrated that the ITS contains useful genetic markers for the
identification of these snail
Polymerase Chain Reaction and Restriction Fragment Length Polymorphism of Cytocrome Oxidase Subunit I Used for Differentiation of Brazilian Biomphalaria Species Intermediate Host of Schistosoma mansoni
The intermediate hosts of Schistosoma mansoni , in Brazil,
Biomphalaria glabrata , B. tenagophila and B. straminea , were
identified by restriction fragment length polymorphism analysis of the
mitochondrial gene cytochrome oxidase I (COI). We performed digestions
with two enzymes (AluI and RsaI), previously selected, based on
sequences available in Genbank. The profiles obtained with RsaI showed
to be the most informative once they were polymorphic patterns,
corroborating with much morphological data. In addition, we performed
COI digestion of B. straminea snails from Uruguay and Argentina
A Low Stringency Polymerase Chain Reaction Approach to the Identification of Biomphalaria glabrata and B. tenagophila, Intermediate Snail Hosts of Schistosoma mansoni in Brazil
The low stringency-polymerase chain reaction (LS-PCR) with a pair of
specific primers for the amplification of the 18S rRNA gene was
evaluated as a means of differentiating between the two Schistosoma
mansoni intermediate host species in Brazil: Biomphalaria glabrata and
B. tenagophila. Individual snails obtained from different states of
Brazil were used and the amplification patterns obtained showed a high
degree of genetic variability in these species. Nevertheless, 4 and 3
clearly defined specific diagnostic bands was observed in individuals
from B. glabrata and B. tenagophila respectively. The detection of
snail specific diagnostic bands suggests the possibility of reliable
species differentiation at the DNA level using LS-PCR
Identification of Planorbids from Venezuela by Polymerase Chain Reaction Amplification and Restriction Fragment Length Polymorphism of Internal Transcriber Spacer of the RNA Ribosomal Gene
Snails of the genus Biomphalaria from Venezuela were subjected to
morphological assessment as well as polymerase chain reaction and
restriction fragment length polymorphism (PCR-RFLP) analysis.
Morphological identification was carried out by comparison of
characters of the shell and the male and female reproductive apparatus.
The PCR-RFLP involved amplification of the internal spacer region ITS1
and ITS2 of the RNA ribosomal gene and subsequent digestion of this
fragment by the restriction enzymes DdeI, MnlI, HaeIII and MspI. The
planorbids were compared with snails of the same species and others
reported from Venezuela and present in Brazil, Cuba and Mexico. All the
enzymes showed a specific profile for each species, that of DdeI being
the clearest. The snails were identified as B. glabrata, B. prona and
B. kuhniana
Molecular Identification of Similar Species of the Genus Biomphalaria (Mollusca: Planorbidae) Determined by a Polymerase Chain Reaction-Restriction Fragment Length Polymorphism
The freshwater snails Biomphalaria straminea, B. intermedia, B.
kuhniana and B. peregrina, are morphologically similar; based on this
similarity the first three species were therefore grouped in the
complex B. straminea. The morphological identification of these species
is based on characters such as vaginal wrinkling, relation between
prepuce: penial sheath:deferens vas and number of muscle layers in the
penis wall. In this study the polymerase chain reaction restriction
fragment length polymorphism technique was used for molecular
identification of these molluscs. This technique is based on the
amplification of the internal transcribed spacer regions ITS1 e ITS2 of
the ribosomal RNA gene and subsequent digestion of these fragments by
restriction enzymes. Six enzymes were tested: Dde I, Mnl I, Hae III,
Rsa I, Hpa II e Alu I. The restriction patterns obtained with DdeI
presented the best profile for separation of the four species of
Biomphalaria. The profiles obtained with all the enzymes were used to
estimate the genetic distances among the species through analysis of
common banding patterns
Suscetibilidade de planorbídeos da região metropolitana de Belo Horizonte, MG (Brasil) ao Angiostrongylus costaricensis (Nematoda, Angiostrongylidae
Biomphalaria glabrata (control), B. tenagophila and B. straminea from our laboratory colonies initiated with molluscs collected in the municipality of Belo Horizonte, MG (Brasil), were experimentally infected with first-stage larvae of Angiostrongylus costaricensis. The number of molluscs of each species exposed was 139, 77 and 149. About 25 days later, surviving molluscs were individually examined by artificial digestion. Of 87 B. glabrata examined, 62 (71.3%) were positive and between one and 61 third-stage larvae were found; of 42 B. tenagophila, 21 (50.0%) contained between one five third-stage larvae; and of 89 B. straminea, 69 (77.5%) presented between one and 72 third-stage larvae. The three molluscan species are susceptible to A. costaricensis infection, but B. glabrata and B. straminea are most suitable for maintaining the nematode cycle in laboratory.Lotes de Biomphalaria glabrata (controle), B. tenagophila e B. straminea (com respectivamente 139, 77 e 149 exemplares) criados em laboratório a partir de espécimes coletados na região metropolitana de Belo Horizonte, MG (Brasil), foram infectados experimentalmente com larvas L1 de Angiostrongylus costaricensis. Decorridos aproximadamente 25 dias, os moluscos foram digeridos individual e artificialmente para exame. De 87 B. glabrata examinadas, 62 (71,3%) estavam positivas e apresentaram de uma a 61 larvas L3; de 42 B. tenagophila, 21 (50,0%) possuíam de uma a cinco L3; e de 89 B. straminea, 69 (77,5%), de uma a 72 L3. As três espécies de planorbídeos mostraram-se suscetíveis à infecção pelo A. costaricensis, sendo a B. glabrata e a B. straminea as mais eficientes para manutenção do ciclo do nematódeo em laboratório