Proteomic analysis of digestive tract peptidases and lipases from the invasive gastropod Pomacea canaliculata

Background

The invasive gastropod Pomacea canaliculata has received great attention in the last decades as a result of its negative impact on crops agriculture, yet knowledge of their digestive physiology remains incomplete, particularly the enzymatic breakdown of macromolecules such as proteins and lipids.

Results

Discovery proteomics revealed aspartic peptidases, cysteine peptidases, serine peptidases, metallopeptidases and threonine peptidases, as well as acid and neutral lipases and phospholipases along the digestive tract of P. canaliculata. Peptides specific to peptidases (139) and lipases (14) were quantified by targeted mass spectrometry. Digestion begins in the mouth via diverse salivary peptidases (nine serine peptidases; seven cysteine peptidases, one aspartic peptidase and 22 metallopeptidases) and then continues in the oesophagus (crop) via three luminal metallopeptidases (Family M12) and six serine peptidases (Family S1). Downstream, the digestive gland provides a battery of enzymes composed of aspartic peptidase (one), cysteine peptidases (nine), serine peptidases (12) and metallopeptidases (24), including aminopeptidases, carboxypeptidases and dipeptidases). The coiled gut has M1 metallopeptidases that complete the digestion of small peptides. Lipid extracellular digestion is completed by triglyceride lipases.

Conclusion

From an integrative physiological and anatomical perspective, P. canaliculata shows an unexpected abundance and diversity of peptidases, which participate mainly in extracellular digestion. Moreover, the previously unknown occurrence of luminal lipases from the digestive gland is reported for the first time. Salivary and digestive glands were the main tissues involved in the synthesis and secretion of these enzymes, but plausibly the few luminally exclusive peptidases are secreted by ventrolateral pouches or epithelial unicellular glands. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

Blocking the expression of syntaxin 4 interferes with initial phagocytosis of Brucella melitensis in macrophages

Brucella melitensis is the Brucella species most frequently associated with brucellosis in humans. It is also the causative agent of the disease in goats and other ruminants. Although significant aspects of the pathogenesis of infection by this intracellular pathogen have been clarified, several events during invasion of host cells remain to be elucidated. In this study, infections of human macrophages from the THP-1 monocyte cell line were conducted with B. melitensis Bm133 wild-type strain and a strain of Salmonella serovar Enteritidis as a control. A multiplicity of infection of 100 was used in trials focused on defining the relative expression of syntaxin 4 (STX4), a soluble N-ethylmaleimide-sensitive factor attachment protein receptor, in the early events of phagocytosis (at 15, 30, 45, and 60 min). Immunoblot assays were also done to visualize expression of the protein in cells infected with either bacterial strain. The expression of STX4 was not significantly different in cells infected with B. melitensis strain Bm133 compared to that observed in cells infected with S. Enteritidis. When the expression of STX4 mRNA was inhibited with short or small interfering, or silencing, RNA in the THP-1 cells, the survival of B. melitensis was significantly reduced at time 0, when gentamicin treatment of cultures was begun (after 1 h of phagocytosis), and also at 2 h and 12 h after infection.     

Soil evaluation for Castanea sativa afforestation in Northeastern Spain

This paper is focused on the soil characterisation of forest sites where Castanea sativa wood stands are located in Catalonia (NE of Spain) as a former and essential requirement to future afforestation programs with this species. From 28 sample plots field survey, several soil indexes have been calculated and, their central and marginal values have been established, defining a range of soil conditions where this species can successfully live in Catalonia. So, we can see that soils are developed on acid bedrock as parent material, basically igneous rocks such as granodiorite and granite, but they occur on schist as well. Their predominant texture is loamy-sand. Soils have low water holding capacity, mainly due to their high stoniness and steep slopes. Nevertheless, regular rainfall distribution all year around, avoids meteorological drought as well as reduces physiological drought. Annual rainfall distribution and steep slopes are responsible for the dwarf development of argic horizons. Soils are relatively poor in organic matter, and despite being generally very acid they have forest mull humus forms.     

Inheritance of resistance to four cucurbit viruses in Cucurbita moschata

Cucurbita moschata cv. Nigerian Local has been used as a source of resistance to Zucchini yellow mosaic virus (ZYMV), Watermelon mosaic virus (WMV), Papaya ringspot virus W (PRSV-W) and Cucumber mosaic virus (CMV) in breeding both Cucurbita moschata and Cucurbita pepo. We used the F₁, F₂ and BC₁ generations derived from the cross C.-moschata cv. Waltham Butternut × Nigerian Local to study the inheritance of resistance to each of the viruses. We confirmed monogenic dominant resistance to ZYMV previously attributed to Zym, and we report monogenic dominant resistance to WMV and CMV which we propose to designate Wmv and Cmv, respectively. A single recessive gene, which we propose to designate prv, controls resistance to PRSV. DNA samples were extracted from a Waltham Butternut BC₁ F₁ population screened with ZYMV and analyzed using randomly amplified polymorphic DNA markers. No RAPD markers linked to ZYMV resistance were found. This revised version was published online in July 2006 with corrections to the Cover Date.     

Genetic relationships among wild and cultivated populations of peach palm (<Emphasis Type="Italic">Bactris gasipaes</Emphasis> Kunth,Palmae): evidence for multiple independent domestication events

We studied the genetic relationship among four wild and ten cultivated populations of peach palm (Bactris gasipaes Kunth) using five microsatellite markers. Peach palm populations were grouped into two major complexes based on morphological traits (see Mora-Urpí 1984, 1993): the Occidental group, including populations found north and west of the Andes Mountains, and the Oriental group, including populations in the Amazon Basin. The Oriental group is further divided into two subgroups, the upper and eastern Amazonia. We also studied two wild relatives of peach palm from the Maracaibo basin in Venezuela. All microsatellite loci were polymorphic and the total number of alleles across all loci was 64. The number of alleles observed per locus ranged from 9 (Bg51) to 16 (Bg63; Average = 12.8 ± 2.8 alleles per locus), while the average number of alleles per population was 31.8 ± 7.3. Our data also revealed that some alleles were common to populations from the same geographical region. A dendrogram based on Rogers and Tanimoto’s similarity coefficient revealed three main branches. The first branch is divided into two nodes and includes all populations from Occidental and Upper Amazonia groups; the second branch includes both populations from Eastern Amazonia, and the third branch includes both wild relatives from Maracaibo. All populations included in each node are neighbors within a geographic region, indicating that populations were finely clustered into their respective geographic groups. We propose that this clustering supports the hypothesis of several independent domestication events on both sides of the Andes, as proposed by Mora-Urpí (1993).     

Serological prevalence of Babesia caballi and Theileria equi in horses of Lara State, Venezuela

The main objective of this study was to demonstrate the occurrence of equine piroplasmosis (EP) in horses of Lara State, Venezuela, and to correlate it with the factors host's sex and age in order to know the epidemiology of this disease at the Venezuelan Centroccidental Region. Antibody levels to Babesia caballi and Theileria equi were assessed in 360 equine serum samples, collected from 9 municipalities of Lara State, using an ELISA technique with recombinant antigens and monoclonal antibodies (Mabs). Antibodies to B. caballi were found in 254 horses (70.6%), whereas 181 animals (50.3%) were detected as seropositives to T. equi. In addition, 128 samples (35.56%) were seropositives to both hemoparasites. There were no significant differences between the seropositivity to B. caballi and T. equi with the factors sex and age of the horses. These results show that Lara State is an enzootic area for equine piroplasmosis, and are a contribution to a partial knowledge of the dynamic of this disease in Venezuela.     

Development of a real-time SYBR Green PCR assay for the rapid detection of Dermatophilus congolensis

Methods such as real time (RT)-PCR have not been developed for the rapid detection and diagnosis of Dermatophilus (D.) congolensis infection. In the present study, a D. congolensis-specific SYBR Green RT-PCR assay was evaluated. The detection limit of the RT-PCR assay was 1 pg of DNA per PCR reaction. No cross-reaction with nucleic acids extracted from Pseudomonas aeruginosa, Mycobacterium tuberculosis, Staphylococcus aureus, or Austwickia chelonae was observed. Finally, the RT-PCR assay was used to evaluate clinical samples collected from naturally infected animals with D. congolensis. The results showed that this assay is a fast and reliable method for diagnosing dermatophilosis.     

Risk factors associated with reproductive performance in small-scale dairy farms in Mexico

Several studies suggest that reproductive performance in small-scale dairy farms is low reducing the farms’ profitability. Therefore, identifying risk factors associated with low reproductive performance is a key step to implement an improved reproductive management program. Accordingly, the aim of the present study was to identify the main risk factors affecting the reproductive performance of cows in small-scale dairy farms. Ninety-six dairy farms were incorporated into this study, and data from 1263 lactations were collected with different events as potential risk factors. Logistic regression models were used to assess the association (odds ratio, OR) and impact (population attributable fraction, PAF) between the potential risk factors and the reproductive variables. The main risk factors associated with assisted calving were male calf and primiparous cows (OR?=?1.7, PAF?=?0.315 and OR?=?1.5, PAF?=?0.131, respectively), while for retained fetal membranes (RFM) were assisted calving and abortion (OR?=?4.5, PAF?=?0.440 and OR?=?8.1, PAF?=?0.239, respectively). The main risk factors for days to first service over 70 days in milk were low body condition score at calving (BCS?≤?2.5) and primiparous cows (OR?=?2.2, PAF?=?0.285 and OR?=?1.4; PAF?=?0.096, respectively), while for days open over 110 days in milk were low BCS at calving (BCS?≤?2.5) and primiparous cows (OR?=?1.7, PAF?=?0.213 and OR?=?1.4; PAF?=?0.096, respectively) The main risk factor for non-pregnant cows at first service was RFM (OR?=?1.7; PAF?=?0.059). In conclusion, assisted calving, male calf, BCS?≤?2.5 and RFM were the main risk factors associated with reduced reproductive performance in small-scale dairy farms in tropical and subtropical regions of Mexico.

     

A non‐invasive method for semen collection and evaluation in small and median size lizards

The aim of this study was to develop a non‐invasive procedure to stimulate ejaculation in median and small lizards for semen collection. After semen collection, we applied a battery of tests to assess the motility (wave and progressive), viability (eosin–nigrosin stain), morphology (normal/abnormal), sperm concentration and ejaculate number, seminal volume and colour. We obtained this fluid from all males of the four species of sceloporine lizards (n = 30) and one species of Mexican horned lizards (n = 7). We found that semen from all males had a liquid‐like consistency and a milky‐white appearance. Ejaculate volume and sperm concentration varied among the males and the species studied. We also observed that although the mobility, viability and normal sperm morphology showed a wide variability, their average value in each species was high. We conclude that “genital papilla pressure” was an efficient and non‐invasive semen obtaining method for small‐ and medium‐sized lizards that does not imply damage to donors and could be used in other lizard species.