Insights into the lemon (Citrus limon) epiphytic microbiome: impact of the biocontrol yeast Clavispora lusitaniae 146.

Background: Postharvest lemons are affected by several fungal infections, and as alternatives to chemical fungicides for combating these infections, different microbial biocontrol agents have been studied, with the Clavispora lusitaniae 146 strain standing out. Although strain 146 has proven to be an effective agent, the influence of a microbial biological control agent on the postharvest lemon microbiome has not been studied until now. Thus, this study aimed to evaluate how the epiphytic microbiome of postharvest lemons is affected by the application of the biocontrol yeast C.

Linear Plasmids in Micrococcus: Insights Into a Common Ancestor and Transfer by Conjugation.

Actinobacteria have frequently been reported in the Andean Puna, including strains of the genus Micrococcus. These strains demonstrate resistance to high levels of UV radiation, arsenic, and multiple antibiotics, and possess large linear plasmids. A comparative analysis of the sequences and putative functions of these plasmids was conducted.

Amphibian skin bacteria display antifungal activity and induce plant defense mechanisms against .

is the causal agent of gray mold, which affects a wide variety of plant species. Chemical agents have been used to prevent the disease caused by this pathogenic fungus. However, their toxicity and reduced efficacy have encouraged the development of new biological control alternatives.

Enhancing biological control of postharvest green mold in lemons: Synergistic efficacy of native yeasts with diverse mechanisms of action.

Argentina is among the most important lemon fruit producers in the world. Penicillium digitatum is the primary lemon fungal phytopathogen, causing green mold during the postharvest. Several alternatives to the use of synthetic fungicides have been developed, being the use of biocontrol yeasts one of the most promising.

Native Cultivable Bacteria from the Blueberry Microbiome as Novel Potential Biocontrol Agents.

Blueberry production is affected by fungal postharvest pathogens, including and , the causative agents of gray mold disease and Alternaria rot, respectively. Biocontrol agents adapted to blueberries and local environments are not known to date. Here, we report on the search for and the identification of cultivable blueberry epiphytic bacteria with the potential to combat the aforementioned fungi.

Assessment of the plasmidome of an extremophilic microbial community from the Diamante Lake, Argentina.

Diamante Lake located at 4589 m.a.s.

Screening Methods for Isolation of Biocontrol Epiphytic Yeasts against in Lemons.

Worldwide, the green rot caused by is one of the most aggressive postharvest diseases of lemons. Searching for sustainable alternatives to chemical fungicides, epiphytic yeasts as potential biocontrol agents were isolated from citrus fruits using a tailor-made selective medium. For disclosing their antagonistic potential against , obtained isolates were subjected to direct screening methods, both in vitro and in vivo.

Killer Yeasts for the Biological Control of Postharvest Fungal Crop Diseases.

Every year and all over the world the fungal decay of fresh fruit and vegetables frequently generates substantial economic losses. Synthetic fungicides, traditionally used to efficiently combat the putrefactive agents, emerged, however, as the cause of environmental and human health issues. Given the need to seek for alternatives, several biological approaches were followed, among which those with killer yeasts stand out.

Protection of Citrus Fruits from Postharvest Infection with and Degradation of Patulin by Biocontrol Yeast 146.

Fungal rots are one of the main causes of large economic losses and deterioration in the quality and nutrient composition of fruits during the postharvest stage. The yeast 146 has previously been shown to efficiently protect lemons from green mold caused by . In this work, the effect of yeast concentration and exposure time on biocontrol efficiency was assessed; the protection of various citrus fruits against by 146 was evaluated; the ability of strain 146 to degrade mycotoxin patulin was tested; and the effect of the treatment on the sensory properties of fruits was determined.

Effect of stress factors associated with postharvest citrus conditions on the viability and biocontrol activity of Clavispora lusitaniae strain 146.

Only quite recently, we have shown that yeast strains Clavispora lusitaniae 146 and Pichia fermentans 27 can act as efficient biocontrol agents for combating postharvest fungal diseases in lemons. During postharvest and storage conditions, microorganisms are subject to different stress factors that could affect both their survival and their protective capacity. Understanding the tolerance of yeasts to environmental stress factors could support the future development and commercial application of biological control formulations based on such organisms.

First Report on the Plasmidome From a High-Altitude Lake of the Andean Puna.

Mobile genetic elements, including plasmids, drive the evolution of prokaryotic genomes through the horizontal transfer of genes allowing genetic exchange between bacteria. Moreover, plasmids carry accessory genes, which encode functions that may offer an advantage to the host. Thus, it is expected that in a certain ecological niche, plasmids are enriched in accessory functions, which are important for their hosts to proliferate in that niche.

Complete Genome Sequences of pLMA1 and pLMA7, Two Large Linear Plasmids of Strains Isolated from a High-Altitude Lake in Argentina.

The two linear plasmids pLMA1 (109,112 bp) and pLMA7 (82,075 bp) from strains were isolated from a high-altitude lake in the Argentinean Puna, sequenced, and annotated. These extrachromosomal elements are probably conjugative and harbor genes potentially involved in coping with the harsh conditions in such extreme environments.

Native Killer Yeasts as Biocontrol Agents of Postharvest Fungal Diseases in Lemons.

Economic losses caused by postharvest diseases represent one of the main problems of the citrus industry worldwide. The major diseases affecting citrus are the "green mold" and "blue mold", caused by Penicillium digitatum and P. italicum, respectively.

Complete Genome Sequence of the Linear Plasmid pJD12 Hosted by Micrococcus sp. D12, Isolated from a High-Altitude Volcanic Lake in Argentina.

The linear plasmid pDJ12 from Micrococcus D12, isolated from the high-altitude volcanic Diamante Lake in the northwest of Argentina, was completely sequenced and annotated. It is noteworthy that the element is probably conjugative and harbors genes potentially instrumental in coping with stress conditions that prevail in such an extreme environment.

First complete sequence of a giant linear plasmid from a micrococcus strain isolated from an extremely high-altitude lake.

Micrococcus sp. strain V7, an actinobacterial strain adapted to the extreme conditions of the Laguna Vilama, an extremely high-altitude (4,600 m above sea level) lake in the Argentinian Puna, was found to carry the giant linear plasmid pLMV7. We determined its sequence (92,815 bp) as a prerequisite to the investigation of its role in survival in such a harsh environment.

Complete Genome Sequence of pAP13, a Large Linear Plasmid of a Brevibacterium Strain Isolated from a Saline Lake at 4,200 Meters above Sea Level in Argentina.

pAP13 is an 89-kb linear plasmid hosted by Brevibacterium sp. strain Ap13, an actinobacterium isolated from the feces of a flamingo from an extremely high-altitude lake in Argentina. Because of the ecological importance of the genus Brevibacterium, the absolute lack of information concerning Brevibacterium linear plasmids, and the possible ecological significance of this unusual plasmid, pAP13 was completely sequenced, including the inversely oriented termini.

Extrachromosomal genetic elements in Micrococcus.

Micrococci are Gram-positive G + C-rich, nonmotile, nonspore-forming actinomycetous bacteria. Micrococcus comprises ten members, with Micrococcus luteus being the type species. Representatives of the genus play important roles in the biodegradation of xenobiotics, bioremediation processes, production of biotechnologically important enzymes or bioactive compounds, as test strains in biological assays for lysozyme and antibiotics, and as infective agents in immunocompromised humans.

Novel linear megaplasmid from Brevibacterium sp. isolated from extreme environment.

Brevibacterium sp. Ap13, isolated from flamingo's feces in Laguna Aparejos, a high-altitude lake located at approximately 4,200 m in the northwest of Argentina was previously found to be resistant to multiple antibiotics, and was therefore screened for plasmids that may be implicated in antibiotic resistance. Brevibacterium sp.