An updated checklist to the biodiversity data of ladybeetles (Coleoptera: Coccinellidae) of the Azores Archipelago (Portugal)

A recently-published review from 2021 presents a comprehensive checklist of ladybeetles of Portugal, including the Azores and Madeira Archipelagos. Until then, the available information was very scattered and based on a single revision dating back to 1986, a few international catalogues and databases, individual records and studies on communities of agroecosystems. However, no information was available on faunal composition across the Azorean islands and their habitats, using standardised inventories. Here, we present data about the biodiversity of ladybeetles and their distribution and abundance in five Islands of the Azores (Faial, Graciosa, Pico, São Jorge and São Miguel). Surveys included herbaceous and arboreal habitats from native to anthropogenic-managed habitats: ruderal road vegetation, vegetable garden, mixed forest of endemic and non-native host plants, coastal prairies, coastal mixed vegetation, cornfields and urban areas. We aimed to contribute to the ongoing effort to document the terrestrial biodiversity of Portugal, including the Archipelago of the Azores, within the research project AZORESBIOPORTAL–PORBIOTA (ACORES-01-0145-FEDER-000072). In this study, a total of 1,487 specimens of Coccinellidae belonging to 19 species are reported for several habitats. The listed species are from one single sub-familiy (Coccinellinae) and six tribes; Chilocorini (one species), Coccidulini (three species), Coccinellini (six species), Noviini (one species), Scymnini (seven species), Stethorini (one species). The number of species collected per island differed; Faial (10 species), Graciosa (four species), Pico (seven species), São Jorge (seven species) and São Miguel (12 species). For six species, new island records are given. Currently, the number of species known to occur in the Azores are 32, including two doubtful records. The majority of species are Scymnini, being Scymnus (Scymnus) interruptus (Goeze, 1777) and Scymnus (Scymnus) nubilus Mulsant, 1850, the most abundant species (relative abundance 71.1%). This database will be the baseline of a long-term monitoring project allowing assessment of the impact of ongoing global changes in the distribution and abundance of ladybeetles.

Heterologous Expression of Pediocin/Papa in Bacillus Subtilis

Listeria moniocytogenes is food-borne pathogen. Pediocin is group II α bacteriocin with anti-listeria activity, naturally produced by Pediococuus acidilactic and Lactobacillus plantarum. Gene pepA/papA encode for pediocin. Expression and secretion of active papA was relayed on transporter papC and accessary protein papD on the same operon in native host. The excretion machines were also necessary for pediocin protein expression in heterologous host of E. coli, Lactobacillus lactis, and Corynebacterium glutamicum. In this study, two vector carrying codon sequence of papA mature peptide was constructed, with or without His tag. Both fragments were inserted into plasmid pHT43 and transformed Bacillus subtilis WB800N. The strains were induced with IPTG to secrete recombination protein PA1 and PA2 respectively. Supernatant from both recombination strains can inhibit Listeria monocytogenes ATCC54003 directly. The fused protein possesses inhibition activity as a whole, exempting from cleavage of leading peptide. Protein PA1 can be purified by nickel-nitrilotriacetic acid (Ni-NTA) metal affinity chromatography. This is the first report for active pediocin expression without assistance of papCD in heterogenous host.

Heterospecific Neighbor Plants Impact Root Microbiome Diversity and Molecular Function of Root Fungi

Within the forest community, competition and facilitation between adjacent-growing conspecific and heterospecific plants are mediated by interactions involving common mycorrhizal networks. The ability of plants to alter their neighbor’s microbiome is well documented, but the molecular biology of plant-fungal interactions during competition and facilitation has not been previously examined. We used a common soil-plant bioassay experiment to study molecular plant-microbial interactions among rhizosphere communities associated with Pinus taeda (native host) and Populus trichocarpa (non-native host). Gene expression of interacting fungal and bacterial rhizosphere communities was compared among three plant-pairs: Populus growing with Populus, Populus with Pinus, and Pinus with Pinus. Our results demonstrate that heterospecific plant partners affect the assembly of root microbiomes, including the changes in the structure of host specific community. Comparative metatranscriptomics reveals that several species of ectomycorrhizal fungi (EMF) and saprotrophic fungi exhibit different patterns of functional and regulatory gene expression with these two plant hosts. Heterospecific plants affect the transcriptional expression pattern of EMF host-specialists (e.g., Pinus-associated Suillus spp.) on both plant species, mainly including the genes involved in the transportation of amino acids, carbohydrates, and inorganic ions. Alteration of root microbiome by neighboring plants may help regulate basic plant physiological processes via modulation of molecular functions in the root microbiome.

The dilution effect in a freshwater mutualism: impacts of introduced host species on native symbionts

The dilution effect was originally proposed to describe the negative effect of increased host diversity on parasite abundance; with greater host diversity, parasite levels per host are predicted to be lower due to a higher probability of dispersing parasites encountering non-competent hosts. Dilution effects could also occur in many mutualisms if dispersing symbionts encounter hosts that vary in their competency. The introduction of non-native hosts can change community competency of a local group of host species. Crayfish introductions are occurring world-wide and these introductions are likely disrupting native crayfish-symbiont systems. Branchiobdellidan symbionts declined on native Cambarus crayfish occurring in the presence and absence of non-native Faxonius crayfish in the New River, USA. We performed an experiment investigating the effect of host density (1 vs 2 native hosts) and host diversity (1 native host and 1 introduced host) on branchiobdellidan abundance. The introduced F. cristavarius is a non-competent host for these worms. Six C. ingens were stocked on a C. chasmodactylus in each treatment and worm numbers were followed over 34 days. Worm numbers decreased over time on C. chasmodactylus alone and in the treatment in which a C. chasmodactylus was paired with an F. cristavarius. Worm numbers remained highest in the 2 C. chasmodactylus treatment . There was no significant effect of host diversity on worm reproduction. Crayfish invasions may have negative effects on mutualistic symbionts depending on the competence of introduced hosts. Loss of native symbionts is one of the potential hidden, negative effects of invasions on native freshwater diversity.

Microbial cell factories for the production of polyhydroxyalkanoates

Pollution caused by persistent petro-plastics is the most pressing problem currently, with 8 million tons of plastic waste dumped annually in the oceans. Plastic waste management is not systematized in many countries, because it is laborious and expensive with secondary pollution hazards. Bioplastics, synthesized by microorganisms, are viable alternatives to petrochemical-based thermoplastics due to their biodegradable nature. Polyhydroxyalkanoates (PHAs) are a structurally and functionally diverse group of storage polymers synthesized by many microorganisms, including bacteria and Archaea. Some of the most important PHA accumulating bacteria include Cupriavidus necator, Burkholderia sacchari, Pseudomonas sp., Bacillus sp., recombinant Escherichia coli, and certain halophilic extremophiles. PHAs are synthesized by specialized PHA polymerases with assorted monomers derived from the cellular metabolite pool. In the natural cycle of cellular growth, PHAs are depolymerized by the native host for carbon and energy. The presence of these microbial PHA depolymerases in natural niches is responsible for the degradation of bioplastics. Polyhydroxybutyrate (PHB) is the most common PHA with desirable thermoplastic-like properties. PHAs have widespread applications in various industries including biomedicine, fine chemicals production, drug delivery, packaging, and agriculture. This review provides the updated knowledge on the metabolic pathways for PHAs synthesis in bacteria, and the major microbial hosts for PHAs production. Yeasts are presented as a potential candidate for industrial PHAs production, with their high amenability to genetic engineering and the availability of industrial-scale technology. The major bottlenecks in the commercialization of PHAs as an alternative for plastics and future perspectives are also critically discussed.

Critical Dependence of Butterflies on a Non-native Host Plant in the Urban Tropics

Increasing urbanization in the tropics has led to the loss of natural habitats and local extirpations and the introduction of non-native plants in urban centers. Non-native plants can have widespread positive and negative ecological implications on native fauna including butterflies. In the small tropical urbanized city-state of Singapore, Aristolochia jackii (Aristolochiaceae), a native host plant of the nationally threatened Common Birdwing (Troides helena) and Common Rose (Pachliopta aristolochiae), is considered extirpated, but their shared non-native host plant Aristolochia acuminata is a cultivated ornamental in urban habitat. We conducted systematic surveys from years 2010 to 2014 and collated sighting records from 1999 to 2019 to map the distribution of T. helena and P. aristolochiae, and their host plant A. acuminata. We utilized machine learning models (i.e., random forest algorithms) to establish the relationships between various habitat (managed and natural tree cover, waterbody and impervious surface cover) and life-history parameters (minimum distance from the nearest larval host plant and population source derived from expert knowledge) that are associated with the butterfly distributions. Response curves were generated for each species and projected spatially across Singapore’s landscape to estimate occupancy. We found that both butterflies had clustered distributions with a greatly reduced probability of occurrence further away from identified population sources and non-native A. acuminata. Both study species had similar spatial niche and similar species occurrence responses though there were differences in habitat preferences and temporal niche. Both species showed positive dependence on managed tree cover (Rose more than Birdwing) but the Birdwing also had high positive dependence on natural tree cover, unlike the Rose. We report novel findings that a non-native host plant can provide positive ecological benefits and critically sustain tropical butterfly populations. While there will be a need to evaluate the full ecological impacts of non-native plantings, we suggest using them as a secondary strategy when re-establishment of the native plants has failed, particularly in highly urbanized tropical landscapes.

Functional and Molecular Characterization of the Halomicrobium sp. IBSBa Inulosucrase

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.