Recovery of Staphylococcus aureus in Gray Mugil cephalus Roe (Bottarga): Investigation by an Integrated Cultural/Molecular Approach

First description of Vibrio harveyi as the causative agent of morbidity and mortality in farmed flathead grey mullet Mugil cephalus

Flathead grey mullet Mugil cephalus is an important species in the aquaculture industry in the Mediterranean basin and throughout the world. During the last 10 yr, M. cephalus breeding stocks, larvae, and juveniles cultured in Eilat (Israel) have shown neurological signs such as uncoordinated circular swimming, while also presenting oral hemorrhages. Death follows days after the onset of the clinical signs, and mortality rates may reach 80% in some cases, causing high economical losses. Bacteriology isolations from different organs, including the brain, and a Koch's postulate experiment, confirmed Vibrio harveyi as the causative agent. Histological analyses showed the presence of the bacterium in different organs. However, in the brain, the bacterium was observed only within blood vessels and meninges. In some samples, mild to severe brain tissue damage was seen. In order to understand the virulence and lethality of V. harveyi, a median lethal dose was calculated, and the result was 106 colony-forming units fish-1. To the best of our knowledge, this is the first report that describes V. harveyi isolated from the brain of M. cephalus and validates it as an etiological agent causing neurological signs in this fish species.

Design of FRET Probes for SNP RS1006737, Related to Mood Disorder

Background:

Several studies have shown that the Single Nucleotide Polymorphism (SNP) in the CACAN1C gene, rs1006737, is related to different mood disorder illnesses, such as bipolar disorder and schizophrenia. Current day molecular procedures for allele detection of this gene can be very expensive and time consuming. Hence, a sensitive and specific molecular procedure for detecting these mutations in a large number of subjects is desirable, especially for research groups who have no complex laboratory equipment.

Objective:

The possibility of using a Fluorescence Resonance Energy Transfer (FRET) probe was evaluated by means of bioinformatic tools, designed for forecasting the molecular behavior of DNA probes used in the research field or for laboratory analysis methods.

Method:

In this study we used the DINAMelt Web Server to predict the Tms of FRET oligo in the presence of the A and/or G allele in rs1006737. The PCR primers were designed by using oligo 4 and oligo 6 primer analysis software,

Results:

The molecular probe described in this study detected a Tm difference of 5-6°C between alleles A and G in rs1006737, which also showed good discrimination for a heterozygous profile for this genomic region.

Conclusion:

Although in silico studies represent a relatively new avenue of inquiry, they have now started to be used to predict how a molecular probe interacts with its biological target, reducing the time and costs of molecular test tuning. The results of this study seem promising for further laboratory tests on allele detection in rs1006737 region.

Sodium Chloride Does Not Ensure Microbiological Safety of Foods: Cases and Solutions

Addition of salt or salt-containing water to food is one of the oldest and most effective preservation methods in history; indeed, salt-cured foods are generally recognized as microbiologically safe due to their high salinity. However, a number of microbiological risks remain. The microbiological hazards and risks associated with salt-cured foods must be addressed more in-depth as they are likely to be underestimated by previous studies. This review examined a number of scientific reports and articles about the microbiological safety of salt-cured foods, which included salted, brined, pickled, and/or marinated vegetables, meat, and seafood. The following subjects are covered in order: (1) clinical cases and outbreaks attributed to salt-cured foods; (2) the prevalence of foodborne pathogens in such foods; (3) the molecular, physiological, and virulent responses of the pathogens to the presence of NaCl in both laboratory media and food matrices; (4) the survival and fate of microorganisms in salt-cured foods (in the presence/absence of additional processes); and (5) the interaction between NaCl and other stressors in food processes (e.g., acidification, antimicrobials, drying, and heating). The review provides a comprehensive overview of potentially hazardous pathogens associated with salt-cured foods and suggests further research into effective intervention techniques that will reduce their levels in the food chain.