Identification and characterization of antimicrobial peptide (AMP) candidate from Gonggong Sea Snail (Leavistrombus turturella) extract.

This study aimed to explore the potency of Gonggong sea snail's (GSS) extract as an antimicrobial peptide (AMP) source. The results showed that the GSS meat extracts exhibited potential antimicrobial activity against Staphylococcus aureus and Escherichia coli. A peptide band with a molecular weight < 5 kDa was obtained for the characterization of AMP candidates after separating the selected extract using SDS-PAGE, and the sequences were acquired by LC-ESI-MS analysis. The results of the bioinformatics analysis showed that the AMP candidate had a molecular weight of 1.4 kDa, which consisted of 12 amino acid residues (RHPDYSVALLLR), with an α-helix structure, isoelectric point pH (pI) of 9.53, net charge + 1, a total hydrophobic ratio at 49.9%, protein-binding potential (Boman index) of 2.17 kcal/mol, and hydrophobicity of + 13.67 kcal/mol. Furthermore, MIC and MBC values of the extract and the < 10 kDa fraction on both bacteria ranged from 0.50-1.03 mg/ml. The GSS meat extract could reach the intracellular site of E. coli, while in S. aureus, it was localized in the cell membrane. These results can be baseline information for developing AMPs in natural bio-preservative exploration as food additives and pharmaceuticals.

Petroleum exploration increases methane emissions from northern peatlands.

Peatlands are globally significant sources of atmospheric methane (CH4). In the northern hemisphere, extensive geologic exploration activities have occurred to map petroleum deposits. In peatlands, these activities result in soil compaction and wetter conditions, changes that are likely to enhance CH4 emissions. To date, this effect has not been quantified. Here we map petroleum exploration disturbances on peatlands in Alberta, Canada, where peatlands and oil deposits are widespread. We then estimate induced CH4 emissions. By our calculations, at least 1900 km2 of peatland have been affected, increasing CH4 emissions by 4.4-5.1 kt CH4 yr-1 above undisturbed conditions. Not currently estimated in Canada's national reporting of greenhouse gas (GHG) emissions, inclusion would increase current emissions from land use, land use change and forestry by 7-8%. However, uncertainty remains large. Research further investigating effects of petroleum exploration on peatland GHG fluxes will allow appropriate consideration of these emissions in future peatland management.

Access roads impact enzyme activities in boreal forested peatlands.

We investigated the impacts of resource access roads on soil enzyme activities in contrasting forested boreal peatlands (bog and fen). In August 2016, a total of 72 peat samples were collected from twelve 20 m long transects perpendicular to access roads, with a further six samples collected from undisturbed reference areas. Sampling locations represent a range in three variables associated with roads: 1) side of the road (upstream/downstream), 2) distance to a culvert (longitudinal; <2 and >20 m), and 3) distance from the road (lateral; 2, 6, and 20 m). Phenol oxidase and hydrolase (glucosidase, sulfatase, xylosidase, glucosaminidase, and phosphatase) enzyme activities were determined for each sample, in addition to water table depth, phenolic concentration, pH, and peat temperature. The average hydrolase activities in the fen were ~four times higher than in the bog. At the bog, the water table depth, phenolic concentration, pH and the activities of phenol oxidase, sulfatase, glucosidase, xylosidase and glucosaminidase were all significantly influenced by one or more road associated factors. The highest enzyme activities in the bog occurred on the downstream side of the road at plots located far from the culvert. In contrast, the flow of water in the fen was not perpendicular to the road. Consequently, no significant variations in water table depth, phenolic concentration, pH or enzyme activity were found with respect to road associated factors. Results indicate that road crossings in boreal peatlands can indirectly alter enzyme activities, likely as part of a causal chain following changes to hydrology and redox conditions. Two of six investigated enzymes had significantly higher activities in the road disturbed areas compared to undisturbed areas, suggesting ultimately that roads may enhance organic matter decomposition rates. However, adequate hydrologic connections through culverts and road construction parallel to the water flow can minimize the road-induced impacts.