Research Publications (Food Safety)

In Actinobacteria , protein O-mannosyl transferase (Pmt)-mediated protein O-glycosylation has an important role in cell envelope physiology. In S.

Maintaining membrane integrity is of paramount importance to the survival of bacteria as the membrane is the site of multiple crucial cellular processes including energy generation, nutrient uptake and antimicrobial efflux. The DedA family of integral membrane proteins are widespread in bacteria and are associated with maintaining the integrity of the membrane. In addition, DedA proteins have been linked to resistance to multiple classes of antimicrobials in various microorganisms.

Campylobacter is the leading bacterial pathogen that causes human foodborne illnesses worldwide and outbreaks have been associated with consumption of under-cooked chicken livers.  The objectives of this study were to compare two PCR assays for speciation of 250 Campylobacter isolates, to assess antibiotic resistance of the isolates, and to analyze genetic diversity of the quinolone resistance determining regions (QRDR) of the isolates.

Abstract

The emergence of multidrug-resistant bacteria, viruses and tumors is a serious threat to public health. Among natural peptides, indolicidin, a 13-residue peptide belonging to the cathelicidin family, deserves special attention. Indolicidin has a broad spectrum of biological activity and is active against a wide range of targets, such as bacteria (Gram+  and Gram−), fungi and viruses.

Author(s): Carmen Igualada, Jennifer Giraldo, Guillermina Font, Vicent Yusà

Author(s): Gulnihal Ozbay, Balaji Kubandra Babu, Eric Peatman, Zohreh Mazaheri Kouhanastani

Author(s): L. Guardone, L. Tinacci, A. Armani, M. Trevisani

Recently reported peptidomimetics with increased resistance to trypsin were shown to sensitize priority multidrug-resistant (MDR) Gram-negative bacteria to novobiocin and rifampicin. To further optimize proteolytic stability, β-amino acid-containing derivatives of these compounds were prepared, resulting in three dioctanoyl ultrashort tetrabasic β-peptides (dUSTBβPs).

The fungal phosphatidylserine (PS) synthase, a membrane protein encoded by the CHO1 gene, is a potential drug target for pathogenic fungi, such as Candida albicans. However, both substrate-binding sites of C. albicans Cho1 have not been characterized. Cho1 has two substrates: cytidyldiphosphate-diacylglycerol (CDP-DAG) and serine. Previous studies identified a conserved CDP-alcohol phosphotransferase (CAPT) binding motif, which is present within Cho1.

β-defensins are antimicrobial peptides presenting in vertebrate animals. They participate in innate immunity, but little is known about them in reptiles, including snakes. Although several β-defensin genes were described in Brazilian snakes, their function is still unknown.

Antimicrobial peptides (AMPs) constitute a broad range of bioactive compounds in diverse organisms, including fish. They are effector molecules for the innate immune response, against pathogens, tissue damage and infections. Still, AMPs from African Catfish, Clarias gariepinus, skin mucus are largely unexplored despite their possible therapeutic role in combating antimicrobial resistance.

Maintaining membrane integrity is of paramount importance to the survival of bacteria as the membrane is the site of multiple crucial cellular processes including energy generation, nutrient uptake and antimicrobial efflux. The DedA family of integral membrane proteins are widespread in bacteria and are associated with maintaining the integrity of the membrane. In addition, DedA proteins have been linked to resistance to multiple classes of antimicrobials in various microorganisms.

Anoplin is a linear 10-amino acid amphipathic peptide (Gly-Leu-Leu-Lys-Arg-Ile-Lys-Thr-Leu-Leu-NH2) derived from the venom sac of the solitary wasp. It has broad antimicrobial activity, including an antibacterial one. However, the inhibition of bacterial growth requires several dozen micromolar concentrations of this peptide. Anoplin is positively charged and directly interacts with anionic biological membranes forming an α-helix that disrupts the lipid bilayer.

Abstract

Author(s): Yayun Ma, Xiaojian Liu, Xiangyang Zhou, Jingjing Tang, Hongxiang Gan, Juan Yang

Author(s): Yan Yang, Guobing Lin, Lijing Liu, Tainan Lin

by Shiva Izadi, Mokhtar Jalali Javaran, Sajad Rashidi Monfared, Alexandra Castilho

by Clifton K. Fagerquist, Claire E. Dodd

Author(s): Kamran Banan, Dara Hatamabadi, Hanif Afsharara, Bahar Mostafiz, Hadise Sadeghi, Soheil Rashidi, Amirreza Dowlati Beirami, Mohammad-Ali Shahbazi, Rüstem Keçili, Chaudhery Mustansar Hussain, Fatemeh Ghorbani-Bidkorbeh

Campylobacter is the leading bacterial pathogen that causes human foodborne illnesses worldwide and outbreaks have been associated with consumption of under-cooked chicken livers.  The objectives of this study were to compare two PCR assays for speciation of 250 Campylobacter isolates, to assess antibiotic resistance of the isolates, and to analyze genetic diversity of the quinolone resistance determining regions (QRDR) of the isolates.

Microbial species occupying the same ecological niche or codeveloping during a fermentation process can exchange metabolites and mutualistically influence each other’s metabolic states. For instance, yeast can excrete amino acids, thereby cross-feeding lactic acid bacteria unable to grow without an external amino acid supply. The yeast membrane transporters involved in amino acid excretion remain poorly known.

In this study, the dihydropteroate synthase of Staphylococcus aureus was obtained, and its recognition mechanisms for 31 sulfonamide drugs were studied. Results showed that their core structure matched well with the binding pocket of para-aminobenzoic acid, and all the sulfonamide side chains were out of the binding pocket. Hydrogen bonds and hydrophobic interactions were the main intermolecular forces, and the key amino acids were Gly171 and Lys203.

This study aimed to investigate the testicular function of Mugil cephalus that inhabit Wadi El-Rayan lakes. Testes of fish inhabiting the upper lake (site 2) and the lower lake (site 3) of Wadi El-Rayan showed significant decreases in gonadosomatic index, high accumulation levels of six metals, and eight organochlorine pesticide residues.

Microfluidic chip analysis has great potential advantages such as high integration, fast speed analysis, and automatic operation and is widely used not only in biological fields but also in many other analytical areas such as agriculture and food safety. Herein, a fully automatic multi-class multi-residue analysis of veterinary drugs simultaneously in an integrated chip-mass spectrometry (chip-MS) platform was developed.