Bacteriophage infection ofLactococcusspecies can cause serious disruption of dairy fermentation processes. The most common isolates from the dairy environment areSiphoviridaelytic 936-type phages. To gain specific knowledge about this group of phages in Polish dairies, we examined 90 isolates from 8 different locations. Based on restriction fragment length polymorphism analysis, coupled with physiological and molecular studies, the isolated phages were divided into 8 distinct groups. Whole-genome sequencing of single representatives from each phage group provided data about their biology and genetic composition. The phages present an overall conserved genome organization. High sequence homology to another Polish isolate,Lactococcusphage bIBB29, indicates their close phylogenetic relatedness to this strain. Such similarity may be suggestive of a general genome conservation among phages persisting in Polish dairies. Comparative genome analyses with other 936-type phages revealed several discriminative traits, including the presence and position of HNH endonuclease genes, varying number oforfsin the early gene region, and a putative TpeX gene. Interestingly, host range of the sequenced phages was restricted toL.lactissubsp.lactisbiovar.diacetylactisstrains. The results provide new data regarding phages present in the Polish dairy environment and permit analysis of their biology, genome composition and relatedness to otherLactococcus936-type phages.
LactococcusCeduovirus (formerly c2virus) bacteriophages are among the three most prevalent phage types reported in dairy environments. Phages from this group conduct a strictly lytic lifestyle and cause substantial losses during milk fermentation processes, by infecting lactococcal host starter strains. Despite their deleterious activity, there are limited research data concerning Ceduovirus phages. To advance our knowledge on this specific phage group, we sequenced and performed a comparative analysis of 10 new LactococcuslactisCeduovirus phages isolated from distinct dairy environments. Host range studies allowed us to distinguish the differential patterns of infection of L. lactis cells for each phage, and revealed a broad host spectrum for most of them. We showed that 40% of the studied Ceduovirus phages can infect both cremoris and lactis strains. A preference to lyse strains with the C-type cell wall polysaccharide genotype was observed. Phage whole-genome sequencing revealed an average nucleotide identity above 80%, with distinct regions of divergence mapped to several locations. The comparative approach for analyzing genomic data and the phage lytic spectrum suggested that the amino acid sequence of the orf8-encoded putative tape measure protein correlates with host range. Phylogenetic studies revealed separation of the sequenced phages into two subgroups. Finally, we identified three types of phage origin of replication regions, and showed they are able to support plasmid replication without additional phage proteins.
Human milk, the gold standard in infant nutrition, is a unique fluid that provides essential nutrients such as lactose, lipids, proteins, and free oligosaccharides. While its primary role is nutritional, it also protects against pathogens. This protection mainly comes from immunoglobulins, with human milk oligosaccharides (HMOs) providing additional support by inhibiting pathogen binding to host cell ligands. The prebiotic and immune-modulatory activity of HMOs strongly depends on their structure. Over 200 individual structures have been identified so far, with the composition varying significantly among women. The structure and composition of HMOs are influenced by factors such as the Lewis blood group, secretor status, and the duration of nursing. HMO profiles are heavily influenced by maternal phenotypes, which are defined based on the expression of two specific fucosyltransferases. However, recent data have shown that HMO content can be modified by various factors, both changeable and unchangeable, including diet, maternal age, gestational age, mode of delivery, breastfeeding frequency, and race. The first part of this overview presents the historical background of these sugars and the efforts by scientists to extract them using the latest chromatography methods. The second part is divided into subchapters that examine modifiable and non-modifiable factors, reviewing the most recent articles on HMO composition variations due to specific reasons and summarizing potential future challenges in conducting these types of studies.
Rheumatoid arthritis (RA) is a prevalent autoimmune disease characterized by chronic joint inflammation. Its pathophysiology involves complex interactions among immune cells, leading to joint damage, primarily in the synovial membrane. MicroRNAs (miRs), single-stranded non-coding RNAs, play a critical role in regulating pathways affecting RA progression, particularly in fibroblast-like synoviocytes and peripheral blood mononuclear cells. Key pathways influenced by miRs include NF-κB, apoptosis, PI3K/AKT signaling, and cytokine production. Dysregulated miRs impact cell proliferation, survival, and inflammatory responses. This review explores not only the role of miRs in RA pathogenesis, but also highlights their potential as biomarkers for early detection and severity prediction. Moreover, therapeutic approaches targeting miRs, including mimics and inhibitors, show promise in animal models, with methods like intra-articular administration being favored due to better efficacy and reduced side effects. While early studies highlight potential pathways for RA treatment, challenges remain in translating these findings into safe and effective clinical therapies.
Free-living amoebae (FLA) are prevalent in diverse environments, representing various genera and species with different pathogenicity. FLA-induced infections, such as the highly fatal amoebic encephalitis, with a mortality rate of 99%, primarily affect immunocompromised individuals while others such as Acanthamoeba keratitis (AK) and cutaneous amebiasis may affect immunocompetent individuals. Despite the prevalence of FLA, there is a lack of standardized guidelines for their detection near human habitats. To date, no studies on the isolation and identification of FLA in environmental soil samples in Warsaw have been published. The aim of this study was to determine the presence of amoebae in soil samples collected from Warsaw parks and squares frequented by humans. The isolated protozoa were genotyped. Additionally, their pathogenic potential was determined through thermophilicity tests. A total of 23 soil samples were seeded on non-nutrient agar plates (NNA) at 26 °C and monitored daily for FLA presence. From the total of 23 samples, 18 were positive for FLA growth in NNA and PCR (78.2%). Acanthamoeba spp. was the most frequently isolated genus, with a total of 13 positive samples (13/18; 72.2%), and the T4 genotype being the most common. Moreover, Platyamoeba placida (3/18; 16.7%), Stenamoeba berchidia (1/18; 5.6%) and Allovahlkampfia sp. (1/18; 5.6%), also potentially pathogenic amoebae, were isolated. To our knowledge, this is the first report of FLA presence and characterization in the Warsaw area.