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The phytopathogen Pseudomonas syringae pv. actinidiae ( Psa) is the causal agent of bacterial canker of kiwifruit. In the last years, it has caused severe economic losses to Actinidia spp. cultivations, mainly in Italy and New Zealand. Conventional strategies adopted did not provide adequate control of infection. Phage therapy may be a realistic and safe answer to the urgent need for novel antibacterial agents aiming to control this bacterial pathogen. In this study, we described the isolation and characterization of two bacteriophages able to specifically infect Psa. φPSA1, a member of the Siphoviridae family, is a temperate phage with a narrow host range, a long latency, and a burst size of 178; φPSA2 is a lytic phage of Podoviridae family with a broader host range, a short latency, a burst size of 92 and a higher bactericidal activity as determined by the TOD value. The genomic sequence of φPSA1 has a length of 51,090 bp and a low sequence homology with the other siphophages, whereas φPSA2 has a length of 40 472 bp with a 98% homology with Pseudomonas putida bacteriophage gh-1. Of the two phages examined, φPSA2 may be considered as a candidate for phage therapy of kiwifruit disease, while φPSA1 seems specific toward the recent outbreak's isolates and could be useful for Psa typing. [ABSTRACT FROM AUTHOR]

The increased antibiotic use (for humans/animals, in clinics and agriculture) leads to the propagation of resistant variants in microbial communities. This phenomenon has been verified for bacterial communities in water and sediments of Tiber River. The heterotrophic aerobic isolates were checked for resistance to ampicillin, chloramphenicol, streptomycin, sulfadimethoxine and tetracycline. From 1 to 5 resistances were found in more than 80% of isolates. Sulfadimethoxine and tetracycline were ascertained to be the most and the least diffuse resistances, respectively. Resistance incidence is independent from the variation in total microbial count. Multiresistance was also observed, and 5-antibiotic-resistant isolates were mainly found in sediments. The resistance pattern has been explained in term of use and persistence of the different antimicrobials. [ABSTRACT FROM AUTHOR]

Vibrio vulnificus is a gram-negative, opportunistic human pathogen associated with life-threatening wound infections and is commonly found in warm coastal marine water environments, globally. In this study, two fishing harbors and three tributaries of the river basin were analyzed for the prevalence of V. vulnificus in the water bodies and shellfish that are under the pressure of external pollutions. The average detection rate of V. vulnificus in the river basins and fishing harbors was 8.3% and 4.2%, respectively, in all seasons. A total of nine strains of V. vulnificus were isolated in pure cultures from 160 samples belonging to river basins and fishing harbors to analyze the antibiotic susceptibility, virulence gene profiles, and enterobacterial repetitive intergenic consensus PCR (ERIC-PCR) fingerprinting. All isolates were susceptible to 10 tested antibiotics. The genotypic characterization revealed that 11.1% (n = 1/9) strain was nonvirulent, whereas 88.9% (n = 8/9) isolates were virulent strains, which possessed the four most prevalent toxin genes such as vcgC (88.9%), 16S B (88.9%), vvhA (88.9%), and manIIA (88.9%), followed by nanA (77.8%), CPS1 (66.7), and PRXII (44.4%). Additionally, ERIC-PCR fingerprinting grouped these nine isolates into two main clusters, among which the river basin isolates showed genetically diverse profiles, suggesting multiple sources of V. vulnificus. Ultimately, this study highlighted the virulent strains of V. vulnificus in the coastal aquatic environments of Taiwan, harboring a potential risk of infection to human health through water-borne transmission. [ABSTRACT FROM AUTHOR]

Although extensive efforts have been made to investigate the dynamics of the occurrence and abundance of antibiotic resistance genes (ARGs) in wastewater treatment plants (WWTPs), understanding the acquisition of antibiotic resistance based on the WWTP scale and the potential effects on WWTPs is of relatively less interest. In this study, metagenomic analysis was carried out to investigate whether the WWTP scale could be affected by the prevalence and persistence of ARGs and mobile genetic elements (MGEs). As a result, 152 ARG subtypes were identified in small-scale WWTP samples, while 234 ARG subtypes were identified in large-scale WWTP samples. Among the detectable ARGs, multidrug, MLS (macrolide–lincosamide–streptogramin), sulfonamide, and tetracycline resistance genes had the highest abundance, and large and small WWTPs had similar composition characteristics of ARGs. In MGE analysis, plasmids and integrons were 1.5–2.0-fold more abundant in large-scale WWTPs than in small-scale WWTPs. The profile of bacteria at the phylum level showed that Proteobacteria and Actinobacteria were the most dominant bacteria, representing approximately 70% across large- and small-scale WWTPs. Overall, the results of this study elucidate the different abundances and dissemination of ARGs between large- and small-scale WWTPs, which facilitates the development of next-generation engineered wastewater treatment systems. [ABSTRACT FROM AUTHOR]

Leather products, used in many ways over centuries, can easily undergo biodeterioration. Modern hides are often damaged by red patches, known as red heats; historical parchments show similar signs of biodeterioration, the purple spots. A two-phases ecological succession explained the parchment biodeterioration process, identifying Halobacterium salinarum as the main culprit of purple spots, entering together with salt into the hide during the brining, in the first phase; whilst the second phase changes with the history of each parchment (Migliore et al., 2017, 2019). To evaluate if similar biodeterioration dynamics can be identified in both leather and parchment, a multidisciplinary study was performed on present-day leathers. This approach consisted of standard cultivation methods and molecular, chemical and physical updated technologies, as Next-Generation Sequencing (NGS), Raman spectroscopy and Transmitted Light Analysis (LTA). As a whole, (i) NGS demonstrated that leathers share the same triggering halophilic agents responsible for the parchment damage; (ii) Raman analyses detected bacteriorhodopsin in red patches; (iii) LTA showed that chrome tanning, conversely to parchment procedure, chemically stabilizes even the damaged areas, making leather products persistent. [ABSTRACT FROM AUTHOR]

A yellow pigmented and agar-pitting colony was isolated from a water sample obtained from a drainage ditch within a disused system of constructed wetlands. The strain was purified and named MCT13 T . This rod-shaped, Gram-negative, oxidase- and catalase-positive, aerobic, non-spore-forming, and non-motile strain formed round colonies and grew optimally at pH 7.5±0.2, at 28-30 °C on LB agar, with 0-0.5 % NaCl. The 16S rRNA gene sequence analysis placed the MCT13 T isolate within the Sphingomonas (sensu stricto) cluster. The DNA G+C content was 65.3 %. The only observed ubiquinone was Q10. The major fatty acids included C17 : 1ω6c and C18 : 1ω7c/C18 : 1ω6c. The major polar lipids were sphingoglycolipid, diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. The major polyamine was spermidine. The 16S rRNA gene phylogenetic analysis performed on the whole sequence, showed the closest relative of MCT13 T to be Sphingomonas koreensis (98.52 %); however, there are several genotypic and phenotypic differences between the novel isolate and the type strain JSS26 T of S. koreensis. On the basis of these results, strain MCT13 T represents a novel species in the genus Sphingomonas, for which the name Sphingomonas turrisvirgatae sp. nov. is proposed. The type strain is MCT13 T (=DSM 105457 T =BAC RE RSCIC 7 T ).