Which Species of Coconut Moth Occurs in Brazil: Atheloca subrufella vs. Atheloca bondari (Lepidoptera: Pyralidae)?

The moths, Atheloca subrufella (Hulst 1887) and A. bondari, (Heinrich 1956) are species known for their economic impact on coconut production, which Brazil is the fourth largest global producer. The first record of Atheloca in Brazil was reported by Bondar in 1940, where the author registered it being A. subrufella. The studies performed by C. Heinrich in 1956 related the existence of divergence in specimens of Brazilian Atheloca suggesting the presence of morphological differences between the males of A. bondari and A. subrufella. In this study, Atheloca specimens from the five states of northeastern Brazil were used. Samples from Pernambuco state were sent to taxonomist Dr. V. O. Becker (Uiraçu Institute-BA) for identification. Male individuals from the other states were mounted for photographic documentation, highlighting the characteristics that differentiate the two species. A fragment of the cytochrome c oxidase subunit 1 gene was sequenced and then compared with that of the Atheloca spp. deposited in GenBank. An analysis was conducted to evaluate the genetic distance between A. bondari and A. subrufella. The results indicate greater interspecific (0.030-0.034) than intraspecific (0.000-0.002) genetic variation between the groups, reinforcing the hypothesis of two distinct species. A geographic distribution map and a table with the host plants were constructed based on a literature review. This study concluded that the species occurring in Brazil is A. bondari, as suggested by C. Heinrich. Atheloca bondari and A. subrufella have only been reported in plants of the family Arecaceae, but only the coconut tree (Cocos nucifera L.) is shared by the two species.

ITS2 as a molecular marker for the identification of Diatraea saccharalis and D. flavipennella and possible infection with Cotesia spp.

In Brazil, the species Diatraea flavipennella and D. saccharalis play an important role in the sugar and alcohol agribusiness by causing many damages in sugarcane fields. The egg, larva, pupa, and adult stages are very morphologically similar between these species, and the identification can be confused. The internal transcribed spacer 2 (ITS 2) from ribosomal DNA has important features as evolutionary divergence. It is a good marker for species identification, participates in the rDNA processing, and has been applied in phylogenetic and population studies. This study aimed to make available a molecular marker to assist on the identification method of pests' species of Diatraea and to identify possible traces of Cotesia in the resistant host. The DNA was extracted from the egg, larva, and adult samples. PCR amplicons were purified and sequenced. The sequences were analyzed in MEGA 5.01. The ITS 2 length was 410 bp in D. flavipennella and 448 bp in D. saccharalis. The GC content was similar between the species. Three microsatellite loci were present in D. saccharalis and absent in D. flavipennella, contributing to differences in ITS 2 length in the species. An additional 367-bp band was attributed to Cotesia spp. The differences among ITS 2 from D. flavipennella, D. saccharalis, and Cotesia sp were sufficient to identify them on electrophoresis gel and sequencing. The presence of Cotesia sp traits in adult D. flavipennella showed possible host refractoriness, but further studies are necessary.

Cholesterol and ergosterol affect the activity of Staphylococcus aureus antibiotic efflux pumps.

The aim of this study is to evaluate the effect of ergosterol on steroids and cholesterol efflux pumps in multidrug resistant strains of S. aureus. Were used RN4220 harboring plasmid pUL5054, which carries the gene encoding the MsrA macrolide efflux protein; and IS-58, which possesses the TetK tetracycline efflux protein; 1199B resists hydrophilic fluoroquinolones via a NorA-mediated mechanism and wild strain 1199B. The Minimal Inhibitory Concentration (MIC) was determined and the evaluation of possible inhibition of efflux pumps by reduction of MIC. Some of the detrimental effects on bacterial cells can be attributed to the detergent properties of cholesterol and ergosterol on account of their amphipathic structure. Besides the cholesterol did not affect directly the pump structure, a synergism was observed, maybe due the interaction with the cell membrane and interference in the lipid bilayer.

Novel DNA extraction assay for molecular identification of Aedes spp eggs.

Aedes aegypti and A. albopictus represent the two most important species of mosquitoes in relation to dengue virus transmission both in the Americas and Asia. However, the study of theses species generally requires the establishment of a colony for the larvae to hatch, or waiting for the adult development to perform its taxonomic classification, which is time consuming. Thus, the establishment of new methods aimed at obtaining DNA directly from the mosquito eggs is relevant. Accordingly, we compared a new approach based on Chelex(®) 100 resin with the standard STE method to extract DNA from the eggs of Aedes spp to molecularly identify these vectors. The Chelex(®) 100 resin approach was very efficient, as satisfactory amounts of DNA were obtained, making it possible to amplify and sequence a mitochondrial DNA barcode region widely used to identify species. The STE protocol yielded substantial amounts of DNA, but the 260/280 optical density ratio indicated a low quality, precluding amplification. This new method proved quite effective in obtaining DNA from even a single mosquito egg, and it can thus be applied in population genetic studies of various vector insects to enhance monitoring programs.

Comparison of two PCR strategies for the detection of bovine papillomavirus.

Bovine papillomavirus (BPV) is a diverse group of double-stranded DNA oncogenic viruses, which have been detected in epithelial lesions and body fluids. Most studies of BPV infection rely on a single method for DNA detection; however the use of any single method or technique may underestimate the true prevalence of this virus. The purpose of this study was to compare two PCR strategies for the detection of BPV in skin lesions and fluids: these involve the use of BPV type-specific and consensus primers. Seventy-two cutaneous lesions, 57 blood samples and 59 semen samples were collected. PCR was used with the FAP consensus primers and BPV type-specific primers (for BPVs 2, 3, 4, 5, 8, 9 and 10), along with sequencing assays, to detect the BPV types. Phylogenetic analysis was carried out by means of the maximum likelihood method. It was found that both FAP and BPV type-specific primer sets could amplify BPV types of DNA in skin lesions, blood and semen samples. However, the BPV type-specific primers were more sensitive than the consensus primers and were able to detect co-infection of BPV in the samples. The consensus primers amplified five BPV types and were more suitable for detecting new putative BPV types. Thus, account should be taken of both PCR primer systems to identify co-infection, the presence of novel viruses, and avoid false-negative results.

Entropy-based approach for selecting informative regions in the L1 gene of bovine papillomavirus for phylogenetic inference and primer design.

Bovine papillomaviruses (BPVs) cause many benign and malignant lesions in cattle and other animals. Twelve BPV types have been identified so far, and several putative novel BPV types have been detected based on the analysis of L1 gene fragments, generated by FAP59/64 and MY11/09 primers. Phylogenetic trees are important in studies that describe novel BPV types. However, topological mistakes could be a problem in such studies. Therefore, we made use of entropy to find phylogenetic informative regions in the BPV L1 gene sequences from all 12 BPVs. Six data sets were created and phylogenetically compared to each other using neighbor-joining and maximum likelihood methods of phylogenetic tree reconstruction. We found two major regions in the L1 gene, using an entropy-based approach, which selects regions with low information complexity. More robust phylogenetic trees were obtained with these regions, when compared to the ones obtained with FAP59/64 and MY11/09 primers. More robust phylogenetic trees are important to accurately position novel BPV types, subtypes and variants. We conclude that an entropy-based approach is a good methodology for selecting regions of the L1 gene of BPVs that could be used to design more specific and sensitive degenerate primers, for the development of improved diagnostic methods.

Genetic diversity of Yersinia pestis in Brazil.

Plague outbreaks are occasionally reported in Brazil. Unfortunately, due to great genetic similarity, molecular subtyping of Yersinia pestis strains is difficult. Analysis of multiple-locus variable number of tandem repeats (VNTR), also known as MLVA, has been found to be a valuable tool to discriminate among strains. To check for genetic differences, strains obtained from two different ecological complexes in Brazil collected during two different epidemiological events, an epizootic in Sítio Alagoinha in 1967 and an outbreak in Planalto da Borborema in 1986, were subtyped through MLVA using 12 VNTR loci. Three clusters (A, B and C) were observed. Of the 20 strains from the epizootic, 18 fit into cluster A. Cluster A was divided into two subgroups: A(1) (15 strains) and A(2) (3 strains). Of the 17 strains from the outbreak, 15 fit into cluster B. Cluster B was divided into three subgroups: B(1) (4 strains), B(2) (4 strains) and B(3) (7 strains). Cluster C is a singleton with one epizootic strain. The external standards, Y. pestis CO92 and Y. pseudotuberculosis IP32953, formed two clusters of singletons. The stability of 12 VNTR loci of three unrelated cultures included in this study was assessed. The 12 VNTR loci were stable through multiple serial subcultures in the laboratory. MLVA revealed that Y. pestis populations in Brazil are not monomorphic, and that there is intraspecific genetic diversity among Brazilian plague strains. We conclude that there is some correlation among genetic groups of this species, related to the temporal and geographic origin of isolates.

Detection of bovine papillomavirus types, co-infection and a putative new BPV11 subtype in cattle.

The aim of this study was to evaluate the presence of different types of Bovine papillomavirus (BPV) in cattle skin lesions and to identify new viral types in Brazil. A total of 72 skin lesions were analysed from 66 different bovines by PCR using degenerate and specific primers, and subsequent sequencing. Sequencing quality was determined using Staden package with Phred 30. Similarity analysis was performed with BioEdit and BLAST programs to verify the identity with known BPV types. Phylogenetic analysis was carried out using Maximum Likelihood method with TIM3 + G as nucleotide substitution model in PAUP*, and 1000 non-parametric bootstrap replicates. Analyses revealed the presence of ten different types of BPV in the samples, with the exception of BPV7. The presence of co-infections was very high as almost all samples (89%) were co-infected. A putative new BPV11 subtype was also found in lesions from different animals. These results add significant knowledge about the prevalence and diversity of BPV infection in Brazilian cattle, which could be used in future studies aiming at the development of more specific treatment and diagnostic methods.

Structural characterization of acetylcholinesterase 1 from the sand fly Lutzomyia longipalpis (Diptera: Psychodidae).

Acetylcholinesterase (AChE) plays a key role in cholinergic impulse transmission, and it is the target enzyme for organophosphorus and carbamate insecticides. Two genes, AceI and AceII, have been characterized from different insect species, and point mutations in either gene can lead to significant resistance to these classes of insecticides. In this report, we describe the partial characterization of the AceI gene from Lutzomyia longipalpis (Lutz & Neiva) (Diptera: Psychodidae), and we show that the possibility exists for the development of a resistant phenotype to organophosphates and carbamates in sand flies. Our results point to the presence of a single AceI gene in L. longipalpis (LlAce1) and that AChE activity is inhibited by organophosphorus at a concentration of 5 x 10(-5) M. Regarding insecticide resistance, analysis of the truncated LlAce1 cDNA suggests that a single missense mutation leading to a glycine-to-serine substitution at amino acid position 119 (G119S) may arise in L. longipalpis, similar to what has been detected in Anopheles gambiae s.s. Another missense mutation involved in resistant phenotypes, F331W, detected in Culex tritaeniorhynchus Giles, is less likely to occur in L. longipalpis, because it faces codon constraint in this sand fly species. Comparison of the three-dimensional structures of the deduced amino acid sequence of the truncated LLAChE1 with that of An. gambiae and Cx. tritaeniorhynchus also suggests that similar structural modifications due to the missense amino acid changes in the active site gorge are detected in all three insects.

Phlebotomine sandflies (Diptera: Psychodidae) of the Atlantic forest in Recife, Pernambuco state, Brazil: the species coming to human bait, and their seasonal and monthly variations over a 2-year period.

In a study of the phlebotomine sandflies (Diptera: Psychodidae) in a forest reserve in Recife, Pernambuco state, north-eastern Brazil, the sandflies landing on human bait between 1.00 and 1.42 h after sunset were collected weekly for 2 years. Although 10,287 sandflies of 10 Lutzomyia species were collected, almost all (96.5%) of the sandflies caught were Lu. umbratilis. This species and several others caught are potential vectors of some of the Leishmania parasites that cause human disease. The recorded landing rate for Lu. umbratilis peaked, at the high level of 333.3 flies/person-hour, during the collections made in May 2003.The relative rarity in the collections of males of some of the species caught probably indicates that these species do not lek on their bloodmeal sources. It is likely that the sizes of the local populations of species that are not very anthrophilic, such as Lu. flaviscutellata, are much larger than indicated by the collections made on human bait.

First report of Lutzomyia (Nyssomyia) umbratilis Ward & Frahia, 1977 outside of Amazonian Region, in Recife, State of Pernambuco, Brazil (Diptera: Psychodidae: Phlebotominae).

Lutzomyia umbratilis, a known vector of Leishmania guyanensis in the north of Amazon basin, has been exclusively found in the Amazonian region. Here we report for the first time the occurrence of this species in northeastern Brazil. The epidemiological importance of the occurrence of this species in the Atlantic Forest is commented.