Evidence for Internalization of Escherichia coli into the Aerial Parts of Maize via the Root System

Abstract

Escherichia coli introduced into the hydroponic growing medium of maize plants was detected 48 h later in the shoot. Decapitation of root tips or severing of the plant root system at the root-shoot junction enhanced bacterial internalization. The density of the bacteria in shoots of plants with damaged roots or removed root systems was 27.8 and 23.9 times higher than that in plants with intact roots, respectively. The concentration of viable cells in the hydroponic solution decreased over time from 9.3 x 10(6) CFU/ml at the time of inoculation to 8.5 x 10(1) CFU/ml 4 days thereafter. The number of E. coli cells associated with the roots also decreased with time, but a significant decline appeared only at 4 days postinoculation. At the time of sampling for E. coli presence in the shoot, 10(2) CFU/ml was present in the nutrient solution and 8 x 10(3) CFU/g was associated with the roots. The present study is the first to demonstrate internalization of E. coli via the root in a monocotyledonous plant.

Can plants serve as a vector for prions causing chronic wasting disease?

“…24 Similar to protein uptake, root damage has also been identified as a factor enhancing the uptake of viruses and bacteria into plants. 25,26 In soil, the activity of nematodes or other parasites could form lesions in roots that could serve as a port of entry for prions into plants. 27 In our study, plants were grown in solid agarose media and subsequently exposed to PrP TSE solution, an approach that deliberately inflicted root damage to fine root hairs but avoided major damage to the main branches.…”

Internalization and Dissemination of Human Norovirus and Animal Caliciviruses in Hydroponically Grown Romaine Lettuce

“…It has been well established that food-borne bacterial pathogens, such as Escherichia coli O157:H7 and Salmonella, become internalized and disseminated in plant crops, including lettuce, spinach, tomato, and mung bean shoots, via the plant root systems, through wounds in the cuticle, or through stomata in laboratory settings (4,22,25). The efficiency of internalization of bacterial pathogens in plants can be affected by many factors, such as the type of plant, plant stress, bacterial species and strain, bacterial dose, environmental humidity, and temperature (3,13,25,45).…”

Salmonella and Escherichia coli O157:H7 Survival in Soil and Translocation into Leeks (Allium porrum) as Influenced by an Arbuscular Mycorrhizal Fungus (Glomus intraradices)

“…Foodborne bacterial pathogens have been shown to exist on plant surfaces and exhibit the ability to internalize into plant tissues under certain conditions (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15). Home preparation and consumption of leeks was recently associated with an 8-month-long food-borne illness outbreak of Escherichia coli O157:H7 phage type 8 in the United Kingdom.…”