ABSTRACT
To evaluate the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in the pig population in Ireland, nasal swabbing was employed in three abattoirs to screen 440 pigs from 41 geographically distributed farms. One hundred individuals involved in the pig industry were also nasally screened. No MRSA isolates were recovered from the pigs and only two of the humans tested were identified as MRSA carriers. Importantly, MRSA was not obtained from pig producers, veterinarians or abattoir employees, but was isolated from individuals working in the wider pig industry. Multi-locus sequence typing revealed that these isolates belonged to sequence types (ST) ST22 and ST1307; the latter is a previously unreported single locus variant of ST5. Five dust samples from each of the three slaughterhouses were culture-negative for MRSA. These results indicate that porcine colonisation by MRSA, and in particular the animal-related strain MRSA-ST398, was not common in Ireland during the period of study.
Subject(s)
Agriculture , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Occupational Exposure , Swine/microbiology , Animals , Bacterial Typing Techniques/veterinary , Humans , Ireland/epidemiology , Methicillin-Resistant Staphylococcus aureus/classification , Multilocus Sequence Typing/veterinary , Prevalence , Staphylococcal Infections/epidemiology , Staphylococcal Infections/veterinary , Swine Diseases/epidemiologyABSTRACT
The temperate phages PhiCD6356 and PhiCD6365 were isolated and characterised following mitomycin C induction of 43 Clostridium difficile strains. Both phages belong to the Siphoviridae family and have genome sizes of 37,664 bp for PhiCD6356 based on sequence data and approximately 50 kb for PhiCD6365 based on restriction analysis. Protein analysis revealed similar protein profiles and indicated posttranslational processing of the PhiCD6356 major capsid protein. The genome sequence of PhiCD6356 is substantially different from other previously reported phage sequences and a putative function could be assigned to only 21 out of 59 predicted open reading frames. However, the genome organisation closely resembles that of other members of the Siphoviridae family which infect low GC-content Gram-positive bacteria. The modular organisation, genome synteny, presence of cohesive ends and posttranslational processing of the capsid protein suggest PhiCD6356 is a member of the proposed Sfi21-like genera. To our knowledge, this report represents the first C. difficile phage of the Siphoviridae family to be sequenced.
Subject(s)
Bacteriophages/classification , Bacteriophages/genetics , Siphoviridae/genetics , Base Composition/genetics , Base Sequence , Clostridioides difficile/classification , Clostridioides difficile/genetics , Clostridioides difficile/virology , Genome , Open Reading Frames , Siphoviridae/classification , SyntenyABSTRACT
A truncated derivative of the phage endolysin LysK containing only the CHAP (cysteine- and histidine-dependent amidohydrolase/peptidase) domain exhibited lytic activity against live clinical staphylococcal isolates, including methicillin-resistant Staphylococcus aureus. This is the first known report of a truncated phage lysin which retains high lytic activity against live staphylococcal cells.
