Quantitative Proteomic Analysis of Staphylococcus aureus Treated With Punicalagin, a Natural Antibiotic From Pomegranate That Disrupts Iron Homeostasis and Induces SOS

Abstract

Staphylococcus aureus, a bacterial, food-borne pathogen of humans, can contaminate raw fruits and vegetables. While physical and chemical methods are available to control S. aureus, scientists are searching for inhibitory phytochemicals from plants. One promising compound from pomegranate is punicalagin, a natural antibiotic. To get a broader understanding of the inhibitory effect of punicalagin on S. aureus growth, high-throughput mass spectrometry and quantitative isobaric labeling was used to investigate the proteome of S. aureus after exposure to a sublethal dose of punicalagin. Nearly half of the proteins encoded by the small genome were interrogated, and nearly half of those exhibited significant changes in accumulation. Punicalagin treatment altered the accumulation of proteins and enzymes needed for iron acquisition, and it altered amounts of enzymes for glycolysis, citric acid cycling, protein biosynthesis, and purine and pyrimidine biosynthesis. Punicalagin treatment also induced an SOS cellular response to damaged DNA. Transcriptional comparison of marker genes shows that the punicalagin-induced iron starvation and SOS responses resembles those produced by EDTA and ciprofloxacin. These results show that punicalagin adversely alters bacterial growth by disrupting iron homeostasis and that it induces SOS, possibly through DNA biosynthesis inhibition.

The Impact of Type VI Secretion System, Bacteriocins and Antibiotics on Bacterial Competition of Pectobacterium carotovorum subsp. brasiliense and the Regulation of Carbapenem Biosynthesis by Iron and the Ferric-Uptake Regulator

“…Similarly, the possibility of Pcb to encounter SOS-inducing conditions in the phyllosphere such as UV irradiation, nutrient limitation and production of antimicrobial compounds by other bacteria suggest that Pcb can potentially produce bacteriocins while residing in this niche. Once in the rhizosphere, Pcb encounters conditions of limited oxygen and SOS inducing conditions such as antimicrobial compounds produced by other bacteria (Erill et al, 2007; Goyal and Mattoo, 2014; Fang et al, 2017; Thorgersen et al, 2017; Cooper et al, 2018; García-Bayona and Comstock, 2018; Leaden et al, 2018), suggesting that Pcb 1692 may be able to produce bacteriocins but not carbapenem while residing in the rhizosphere, however, this needs to experimentally verified. Finally, once inside potato tubers Pcb encounters several stresses which can trigger bacteria SOS such as nutrient starvation, iron deficiency, chromate stress, osmotic stress, oxidative and acidic stress, and β-lactam antibiotics produced by either bacteria endophytes or the host plant, leading to phage induction and bacteriocin production (Erill et al, 2007; Goyal and Mattoo, 2014; Fang et al, 2017; Thorgersen et al, 2017; Cooper et al, 2018; García-Bayona and Comstock, 2018; Leaden et al, 2018).…”

The impact of type VI secretion system, bacteriocins and antibiotics on competition amongst Soft-RotEnterobacteriaceae: Regulation of carbapenem biosynthesis by iron and the transcriptional regulator Fur

“…Similarly, intake of excess iron can lead to oxidative burst in bacteria through Fenton reaction (72). In addition, the presence of chromate in potato tubers (45, 73) and production of β-lactam antibiotics by either bacteria endophytes or the host plant can trigger an SOS response and hence bacteriocin production (74, 75)…”

Pomegranate Peel Extracts as Safe Natural Treatments to Control Plant Diseases and Increase the Shelf-Life and Safety of Fresh Fruits and Vegetables

“…In this regard, Sudharsan et al [43] observed that PPEs can inhibit aflatoxin production in A. flavus by inhibiting specific enzymes in the pathway of aflatoxin biosynthesis. In addition, a specific study on the proteomic effects of punicalagin on S. aureus showed that it adversely alters bacterial growth by disrupting iron homeostasis and inducing SOS responses, possibly through DNA biosynthesis inhibition [56]. Although some reports suggested that the presence of the outer lipopolysaccharide membrane in Gram-negative bacteria could reduce the ability of PPEs to alter and affect cells, other investigations have shown a high efficacy against Gram-negative bacteria such as Salmonella Enteritidis [36].…”