Polish Journal of Microbiology 

About: Polish Journal of Microbiology is an academic journal published by Exeley Inc. The journal publishes majorly in the area(s): Medicine & Biology. It has an ISSN identifier of 1733-1331. It is also open access. Over the lifetime, 1001 publications have been published receiving 12470 citations. The journal is also known as: PJM Online.

Bacteriophage receptors, mechanisms of phage adsorption and penetration into host cell.

Abstract: Bacteriophages are an attractive tool for application in the therapy of bacterial infections, for biological control of bacterial contamination of foodstuffs in the alimentary industry, in plant protection, for control of water-borne pathogens, and control of environmental microflora. This review is mainly focused on structures governing phage recognition of host cell and mechanisms of phage adsorption and penetration into microbial cell.

The oral microbiome in dental caries.

Abstract: Dental caries is one of the most common chronic and multifactorial diseases affecting the human population. The appearance of a caries lesion is determined by the coexistence of three main factors: acidogenic and acidophilic microorganisms, carbohydrates derived from the diet, and host factors. Socio-economic and behavioral factors also play an important role in the etiology of the disease. Caries develops as a result of an ecological imbalance in the stable oral microbiom. Oral microorganisms form dental plaque on the surfaces of teeth, which is the cause of the caries process, and shows features of the classic biofilm. Biofilm formation appears to be influenced by large scale changes in protein expression over time and under genetic control Cariogenic microorganisms produce lactic, formic, acetic and propionic acids, which are a product of carbohydrate metabolism. Their presence causes a decrease in pH level below 5.5, resulting in demineralization of enamel hydroxyapatite crystals and proteolytic breakdown of the structure of tooth hard tissues. Streptococcus mutans, other streptococci of the so-called non-mutans streptococci group, Actinomyces and Lactobacillus play a key role in this process. Dental biofilm is a dynamic, constantly active metabolically structure. The alternating processes of decrease and increase of biofilm pH occur, which are followed by the respective processes of de- and remineralisation of the tooth surface. In healthy conditions, these processes are in balance and no permanent damage to the tooth enamel surface occurs.

Staphylococcal cassette chromosome mec (Sccmec) classification and typing methods: an overview

Abstract: Meticillin-resistant Staphylococcus aureus (MRSA) is one of the main causes of hospital-acquired infections, but since late 1990s also the community-acquired. For better understanding of the S.aureus epidemiology there is an urgent need for creation of new typing method for SCCmec element. The molecular typing of MRSA for epidemiological purposes is investigated by pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), spa typing and the SCCmec type assignment. In last few years not only new type of SCCmec (VI to XI) have been identified, but also additional subtypes (i.e. IVg-j) and different variants of already existed one (i.e. 5C2&5 and 2B2&5) were discovered. The aim of this review is to briefly summarize current knowledge about SCCmec classification and to discuss advantages and disadvantages of selected SCCmec typing methods.

Bacteriophages as an Alternative Strategy for Fighting Biofilm Development

Abstract: The ability of microbes to form biofilms is an important element of their pathogenicity, and biofilm formation is a serious challenge for today's medicine. Fighting the clinical complications associated with biofilm formation is very difficult and linked to a high risk of failure, especially in a time of increasing bacterial resistance to antibiotics. Bacterial species most commonly isolated from biofilms include coagulase-negative staphylococci, Staphylococcus aureus, Enterococcus faecalis, Enterococcus faecium, Escherichia coli, Proteus mirabilis, Klebsiella pneumoniae, Pseudomonas aeruginosa and Acinetobacter spp. The frequent failure of antibiotic therapy led researchers to look for alternative methods and experiment with the use of antibacterial factors with a mechanism of action different from that of antibiotics. Experimental studies with bacteriophages and mixtures thereof, expressing lytic properties against numerous biofilm-forming bacterial species showed that bacteriophages may both prevent biofilm formation and contribute to eradication of biofilm bacteria. A specific role is played here by phage depolymerases, which facilitate the degradation of extracellular polymeric substances (EPS) and thus the permeation of bacteriophages into deeper biofilm layers and lysis of the susceptible bacterial cells. Much hope is placed in genetic modifications of bacteriophages that would allow the equipping bacteriophages with the function of depolymerase synthesis. The use of phage cocktails prevents the development of phage-resistant bacteria.

Antibacterial study of the medium chain fatty acids and their 1-monoglycerides: individual effects and synergistic relationships.

Abstract: The antibacterial activity of the medium chain fatty acids and their 1-monoglycerides was evaluated towards several Gram-positive strains belonging to the genera Staphylococcus, Corynebacterium, Bacillus, Listeria and Streptococcus. The 1-monoglycerides were more active than the fatty acids with monolaurin being the most active compound. Interesting effects were observed when the streptococcal strain Streptococcus pyogenes was used as a test microorganism. First, blocking of the hydroxyl groups of the glycerol moiety of monolaurin led to a compound with remarkable antibacterial activity (MIC, 3.9 microg/ml). Secondly, synergistic relationships were observed between monolaurin and monocaprin as well as between monolaurin and the poorly active lauric acid when their two component mixtures were examined. The mixtures in which one of the components was 2-fold more predominant than the other one were much more active than the pure components taken individually. Moreover, the presence of the components in ratio 1:1 was disadvantageous. Synergistic relationships were also found between monolaurin and monomyristin towards Staphylococcus aureus 209 when monomyristin was in the same quantity as monolaurin or in shortage.