Plant and Human Pathogenic Bacteria Exchanging their Primary Host Environments

Abstract

Adaptation of plant and human pathogenic bacteria to niches of existence differing from their original ones is a sophisticated mechanism for survival. Research indicates that certain plant bacterial pathogens are capable of causing disease in humans, and some human bacterial pathogens can inhabit the plant environment and cause disease in plants. The infection of humans by plant bacteria may occur at direct physical contact with diseased plants and/or via the respiratory tract in mainly immunocompromised or otherwise stressed individuals. Indirect transmitters of plant and human microbes can be wind, rain, dust, insects, and animals. Human pathogenic bacteria may contaminate the soil and irrigation water, colonize the rhizosphere, more rarely also the phyllosphere, and can survive as epiphytes. Thus, the plant environment may become a reservoir of human pathogens. A source of foodborne human pathogenic bacteria can be unprocessed or unwashed fruits and vegetables. Especially during the last decade, the processes underlying the cross-kingdom performance of pathogenic bacteria are intensively researched. However, in reality, the risk for human health at infections by plant bacteria and by human bacterial pathogens surviving in the plant environment is still underestimated. The goal of the current review is to increase the interest in these issues in agricultural and general environments. Some basic strategies for infection and symptoms of diseases caused by the microorganisms under consideration are described. The potency of certain plant bacterial pathogens to surpass barriers towards humans and the interaction of human bacterial pathogens with the plant environment are addressed and the existing information is critically discussed.

Intraspecies competition among Salmonella enterica isolates in the lettuce leaf apoplast

“…Typhi ( Hoffman and Luby, 2024 ). Moreover, certain species are able to cross the kingdom border, e.g ., phytopathogens may impact human and animal health, while human pathogens might successfully reside in plants ( Kim et al., 2020 ; Sobiczewski and Iakimova, 2022 ). Studies have increasingly shed light into the potential of human pathogenic bacteria to adjust to plant environments, by gaining and/or exploiting traits that enhance their ability to live in these niches ( Holden et al., 2009 ; Warriner and Namvar, 2010 ; van Overbeek et al., 2014 ; Zarkani and Schikora, 2021 ).…”

“…Typhi (Hoffman and Luby, 2024). Moreover, certain species are able to cross the kingdom border, e.g., phytopathogens may impact human and animal health, while human pathogens might successfully reside in plants (Kim et al, 2020;Sobiczewski and Iakimova, 2022). Studies have increasingly shed light into the potential of human pathogenic…”

Product safety aspects of plant molecular farming

“…In addition to harmful molecules produced by plants, PMF hosts may also attract pests and pathogens that can directly harm humans or produce toxic proteins and metabolites, which is an active area of research in the context of food safety ( Fletcher et al, 2013 ; Sobiczewski and Iakimova, 2022 ). For example, fungi that infect cereals produce (ergot) alkaloids and carcinogenic mycotoxins ( Hulvová et al, 2013 ; Florea et al, 2017 ; Sweany et al, 2022 ), the latter including aflatoxin B1 which is toxic at micromolar concentrations ( Bianco et al, 2012 ; Marchese et al, 2018 ).…”

Fresh vegetables and fruit as a source of <i>Salmonella</i> bacteria

“…If they colonize plant surfaces, they are treated as microbial contaminants. Salmonella bacteria also colonize internal plant tissues as endophytes [11,40], penetrating through wounds, stomata, hydatodes and trichomes. Colonization of the plant interior is enabled by the following characteristics of Salmonella: mobility, chemotaxis capacity, presence of a type III secretion system (T3SS), and biofilm formation [11,41].…”