Gut bacteria of Cuora amboinensis (turtle) produce broad-spectrum antibacterial molecules

• Published in: Scientific reports 2019-11, Vol.9 (1), p.17012-19, Article 17012
• Main Authors: Akbar, Noor, Khan, Naveed Ahmed, Sagathevan, K., Iqbal, Mazhar, Tawab, Abdul, Siddiqui, Ruqaiyyah
• Format: Article
• Language: English
• Subjects: 13/106; 631/326/2522; 692/308/153; 82/58; Animals; Anti-Bacterial Agents - metabolism; Anti-Bacterial Agents - pharmacology; Antibacterial activity; Antimicrobial resistance; Bacteria; Bacterial diseases; Bacterial Infections - microbiology; Bacterial Infections - prevention & control; Bactericidal activity; Cell viability; Cuora amboinensis; Drug resistance; E coli; Escherichia coli - drug effects; Escherichia coli - physiology; Flora; Gastrointestinal Microbiome; Homoserine lactones; Host-Pathogen Interactions - drug effects; Humanities and Social Sciences; Intestinal microflora; Klebsiella pneumoniae - drug effects; Klebsiella pneumoniae - physiology; L-Lactate dehydrogenase; Lactic acid; Lactones; Metabolites; Methicillin; Methicillin-Resistant Staphylococcus aureus - drug effects; Methicillin-Resistant Staphylococcus aureus - physiology; Microbial Sensitivity Tests; multidisciplinary; Neuropathology; Organic wastes; Pseudomonas aeruginosa - drug effects; Pseudomonas aeruginosa - physiology; Reptiles; Rhamnolipids; Salmonella enterica - drug effects; Salmonella enterica - physiology; Science; Science (multidisciplinary); Secondary metabolites; Serratia marcescens - drug effects; Serratia marcescens - physiology; Staphylococcus infections; Streptococcus infections; Streptococcus pyogenes - drug effects; Streptococcus pyogenes - physiology; Therapeutic applications; Turtles - microbiology
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-019-52738-w

Antimicrobial resistance is a major threat to human health, hence there is an urgent need to discover antibacterial molecule(s). Previously, we hypothesized that microbial gut flora of animals are a potential source of antibacterial molecules. Among various animals, Cuora amboinensis (turtle) represents an important reptile species living in diverse ecological environments and feed on organic waste and terrestrial organisms and have been used in folk medicine. The purpose of this study was to mine turtle’s gut bacteria for potential antibacterial molecule(s). Several bacteria were isolated from the turtle gut and their conditioned media were prepared. Conditioned media showed potent antibacterial activity against several Gram-positive ( Bacillus cereus , Streptococcus pyogenes and methicillin-resistant Staphylococcus aureus ) and Gram-negative (neuropathogenic Escherichia coli K1, Serratia marcescens, Pseudomonas aeruginosa, Salmonella enterica and Klebsiella pneumoniae ) pathogenic bacteria. Conditioned media-mediated bactericidal activity was heat-resistant when treated at 95°C for 10 min. By measuring Lactate dehydrogenase release, the results showed that conditioned media had no effect on human cell viability. Tandem Mass Spectrometric analysis revealed the presence of various secondary metabolites, i.e., a series of known as well as novel N- acyl-homoserine lactones, several homologues of 4-hydroxy-2-alkylquinolines, and rhamnolipids, which are the signature metabolites of Pseudomonas species. These findings are significant and provide the basis for rational development of therapeutic interventions against bacterial infections.