Efficacy of lyophilized Lactobacillus sakei as a potential candidate for the prevention of carbapenem-resistant Klebsiella infection

Abstract

Background Antimicrobial resistance has been considered one of the greatest threats to human health, according to the World Health Organization (WHO). Gram-negative bacteria, especially carbapenem-resistant Enterobacteriaceae (CRE), drive this alarming trend.Among CRE pathogens, carbapenem-resistant Klebsiella pneumonia (CRKP) has recently been reported as a highly infectious one responsible of a high mortality and morbility in adults and immunocompromised patients. Additionally, CRKP-related infections are challenging to treat, as carbapenems are the last resort of antibiotics. Therefore, developing novel drugs with different mechanism of action from the existing drugs is urgently required to defeat this lethal menace. In these circumstances, probiotics intended for being a potential choice to be a therapeutic candidate and inhibit the pathogens. Thus, our research team has been focusing on probiotics for a long time to develop potential anti-CRKP drug agents. Methods After such efforts, we finally found a novel Lactobacillus sakei PMC104 derived from kimchi, a probiotic strain suitable for treating CRE infection. Next, as part of our expansion into therapeutic development, we did media optimization at food grade and then established a scale-up process to pilot scale. A lyophilizate was then obtained, which was subsequently used in a mouse model infected with CRKP. Results Data showed that treatment with L. sakei powder remarkably diminished the body weight loss, mortality, and illness severity in CRKP-infected mice which shows the preventive effect of our PMC 104 against CRKP infection. Discussion Our results exhibit the potential therapeutic effect of our candidate probiotic strain opposed to the CRKP, advocating that L. sakei can be congested as an antimicrobial candidate for treating CRKP infections. However, extensive studies such as toxicity tests and clinical trials are still needed to develop it as a new anti-CRE therapeutic agent.

Optimizing of Culture Conditions for the Isolation and Characterization of Extracellular Vesicles Derived from Lactobacillus crispatus PMC201

“…The function of EVs varies not only depending on the type and origin of bacteria, but also on the quantity of EVs themselves and conditions of bacteria and their culture methods [28]. Therefore, we used food-grade media [24] instead of conventional MRS media. The secretion of EVs particles was more effectively achieved with the food-grade media than with the MRS media.…”

“…In addition, the corresponding proteome was confirmed. For L. crispatus PMC201, EVs were isolated using food-grade medium [24], a selfdeveloped medium rather than commercial media. Proteomic analysis was then performed using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) [25,26].…”