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A Neisseria gonorrhoeae multilocus sequence type (MLST) ST7363 strain was isolated from a patient at the Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand, in 2010 and completely sequenced. This strain is susceptible to ceftriaxone and cefixime. A complete circular chromosome and circular plasmids were assembled from combined Oxford Nanopore Technologies (ONT) and Illumina sequencing.

Background: Invasive pneumococcal disease remains an important health priority owing to increasing disease incidence caused by pneumococci expressing non-vaccine serotypes. We previously defined 621 Global Pneumococcal Sequence Clusters (GPSCs) by analysing 20 027 pneumococcal isolates collected worldwide and from previously published genomic data. In this study, we aimed to investigate the pneumococcal lineages behind the predominant serotypes, the mechanism of serotype replacement in disease, as well as the major pneumococcal lineages contributing to invasive pneumococcal disease in the post-vaccine era and their antibiotic resistant traits. Methods: We whole-genome sequenced 3233 invasive pneumococcal disease isolates from laboratory-based surveillance programmes in Hong Kong (n=78), Israel (n=701), Malawi (n=226), South Africa (n=1351), The Gambia (n=203), and the USA (n=674). The genomes represented pneumococci from before and after pneumococcal conjugate vaccine (PCV) introductions and were from children younger than 3 years. We identified predominant serotypes by prevalence and their major contributing lineages in each country, and assessed any serotype replacement by comparing the incidence rate between the pre-PCV and PCV periods for Israel, South Africa, and the USA. We defined the status of a lineage as vaccine-type GPSC (≥50% 13-valent PCV [PCV13] serotypes) or non-vaccine-type GPSC (>50% non-PCV13 serotypes) on the basis of its initial serotype composition detected in the earliest vaccine period to measure their individual contribution toward serotype replacement in each country. Major pneumococcal lineages in the PCV period were identified by pooled incidence rate using a random effects model. Findings: The five most prevalent serotypes in the PCV13 period varied between countries, with only serotypes 5, 12F, 15B/C, 19A, 33F, and 35B/D common to two or more countries. The five most prevalent serotypes in the PCV13 period varied between countries, with only serotypes 5, 12F, 15B/C, 19A, 33F, and 35B/D common to two or more countries. These serotypes were associated with more than one lineage, except for serotype 5 (GPSC8). Serotype replacement was mainly mediated by expansion of non-vaccine serotypes within vaccine-type GPSCs and, to a lesser extent, by increases in non-vaccine-type GPSCs. A globally spreading lineage, GPSC3, expressing invasive serotypes 8 in South Africa and 33F in the USA and Israel, was the most common lineage causing non-vaccine serotype invasive pneumococcal disease in the PCV13 period. We observed that same prevalent non-vaccine serotypes could be associated with distinctive lineages in different countries, which exhibited dissimilar antibiotic resistance profiles. In non-vaccine serotype isolates, we detected significant increases in the prevalence of resistance to penicillin (52 [21%] of 249 vs 169 [29%] of 575, p=0·0016) and erythromycin (three [1%] of 249 vs 65 [11%] of 575, p=0·0031) in the PCV13 period compared with the pre-PCV period. Interpretation: Globally spreading lineages expressing invasive serotypes have an important role in serotype replacement, and emerging non-vaccine serotypes associated with different pneumococcal lineages in different countries might be explained by local antibiotic-selective pressures. Continued genomic surveillance of the dynamics of the pneumococcal population with increased geographical representation in the post-vaccine period will generate further knowledge for optimising future vaccine design. Funding: Bill & Melinda Gates Foundation, Wellcome Sanger Institute, and the US Centers for Disease Control. Fil: Lo, Stephanie W.. Wellcome Sanger Institute; Reino Unido Fil: Gladstone, Rebecca A.. Wellcome Sanger Institute; Reino Unido Fil: van Tonder, Andries J.. Wellcome Sanger Institute; Reino Unido Fil: Lees, John A.. University Of New York. School Of Medicine; Estados Unidos Fil: du Plessis, Mignon. National Institute For Communicable Diseases; Sudáfrica Fil: Benisty, Rachel. Ben Gurion University of the Negev; Israel Fil: Givon Lavi, Noga. Ben Gurion University of the Negev; Israel Fil: Hawkins, Paulina A.. University of Emory. Rollins School of Public Health; Estados Unidos Fil: Cornick, Jennifer E.. Malawi liverpool wellcome trust; Malaui Fil: Kwambana Adams, Brenda. University College London; Estados Unidos Fil: Law, Pierra Y.. University of Hong Kong; China Fil: Ho, Pak Leung. University of Hong Kong; China Fil: Antonio, Martin. Medical Research Council Unit The Gambia; Gambia Fil: Everett, Dean B.. University of Edinburgh; Reino Unido Fil: Dagan, Ron. Ben Gurion University of the Negev; Israel Fil: Von Gottberg, Anne. National Institute For Communicable Diseases; Sudáfrica Fil: Klugman, Keith P.. University of Emory. Rollins School of Public Health; Estados Unidos Fil: McGee, Lesley. Centers for Disease Control and Prevention; Estados Unidos Fil: Breiman, Robert F.. University of Emory. Rollins School of Public Health; Estados Unidos Fil: Bentley, Stephen D.. Wellcome Sanger Institute; Reino Unido Fil: Brooks, Abdullah W.. The Global Pneumococcal Sequencing Consortium; Reino Unido Fil: Corso, Alejandra. The Global Pneumococcal Sequencing Consortium; Reino Unido. Dirección Nacional de Institutos de Investigación. Administración Nacional de Laboratorios e Institutos de Salud. Instituto Nacional de Enfermedades Infecciosas. Área de Antimicrobianos; Argentina Fil: Davydov, Alexander. The Global Pneumococcal Sequencing Consortium; Reino Unido Fil: Maguire, Alison. The Global Pneumococcal Sequencing Consortium; Reino Unido Fil: Pollard, Andrew. The Global Pneumococcal Sequencing Consortium; Reino Unido Fil: Kiran, Anmol. The Global Pneumococcal Sequencing Consortium; Reino Unido Fil: Skoczynska, Anna. The Global Pneumococcal Sequencing Consortium; Reino Unido Fil: Moiane, Benild. The Global Pneumococcal Sequencing Consortium; Reino Unido Fil: Beall, Bernard. The Global Pneumococcal Sequencing Consortium; Reino Unido Fil: Sigauque, Betuel. The Global Pneumococcal Sequencing Consortium; Reino Unido Fil: Aanensen, David. The Global Pneumococcal Sequencing Consortium; Reino Unido Fil: Lehmann, Deborah. The Global Pneumococcal Sequencing Consortium; Reino Unido Fil: Faccone, Diego Francisco. Dirección Nacional de Institutos de Investigación. Administración Nacional de Laboratorios e Institutos de Salud. Instituto Nacional de Enfermedades Infecciosas. Área de Antimicrobianos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

We surveyed group C and group G β-hemolytic streptococci for emm and emmL (emm -like) genes which encode the M protein, as well as determined their antimicrobial susceptibilities. A total of 97 isolates 79 GCS/GGS isolates and 18 isolates from other groups were tested for the M protein gene by PCR. Focusing on invasive infections with group A (GAS), group C (GCS), and group G (GGS) β-hemolytic streptococci isolated from blood, the M protein gene was found in 90.0%, 84.6%, and 78.3% of isolates, respectively. The hypervariable N terminal region of the emm was sequenced from 62 isolates, and 26 types of the emm gene were identified. Based on these results, type emm222.2 may be endemic to Thailand. The results of antimicrobial susceptibility testing of groups C, G, and non-groups A to G isolates indicated high susceptibility (range 82-100%) to penicillin, cefotaxime, chloramphenicol, clindamycin, erythromycin, linezolid, ofloxacin, and vancomycin, whereas the isolates showed low susceptibility (range 0-15.6%) to tetracycline.

We studied the antimicrobial susceptibility and prevalence of the blaTEM-1 and blaTEM-135 genes in Neisseria gonorrhoeae isolates obtained in Thailand. The isolates were tested using the disk diffusion method, and 100% of 370 isolates were found susceptible to cefixime, ceftriaxone, cefotaxime, ceftazidime, cefepime, spectinomycin, and azithromycin. Some of the isolates were resistant to penicillin (85.7%), ciprofloxacin (88.0%), ofloxacin (97.4%), or tetracycline (89.1%). Penicillinase-producing N. gonorrhoeae accounted for 83.8% of isolates, with 70.0% of these further identified as penicillinase-producing plus tetracycline resistant N. gonorrhoeae. Penicillin, tetracycline, and ciprofloxacin are not recommended for treatment because of the high prevalence (89.7%) of multidrug resistant gonococci. A study of genes controlling enzyme of beta-lactamase production (blaTEM-1 and blaTEM-135) was performed using mismatch amplification mutation assay PCR method and DNA sequencing. Beta-lactamase positive N. gonorrhoeae carried blaTEM-1 (69.6%) and blaTEM-135 (30.4%), indicating that there is a significant increase and spread of blaTEM-135 among gonococci in Thailand.

Background: Siderophore is an iron chelator produced by microorganism. Pseudomonas aeruginosa produces two siderophores (pyoverdin and pyochelin). Desferrioxamine is a siderophore used in thalassemia patients to treat an iron overload of vital organs. Objective: Compare the ability of pyoverdin, pyochelin, and desferrioxamine for iron mobilization from ferritin. Materials and Methods: In vitro experiment, the ability of P. aeruginosa siderophores and desferrioxamine for iron mobilization from ferritin was compared by using a dialysis membrane assay at pH values of 7.4 and 6.0. Stimulation of P. aeruginosa PAO1 growth by all siderophores was studied in glucose minimum medium. Results: All three compounds were capable of iron mobilization at both pHs. At pH 6.0, the most effectiveness compound was desferrioxamine (31.6%), followed by pyoverdin (21.5%) and pyochelin (13.7%) compared on weight basis, each at 10 μg/mL. At equimolar concentration, their activities were desferrioxamine (38.5±1.2%), followed by pyoverdin (32.0±4.8%) and pyochelin (26.7±1.9%), respectively. Conclusion: The most effective compound in iron mobilization from ferritin was desferrioxamine, followed by pyoverdin and pyochelin respectively.

Neisseria gonorrhoeae is a major public health problem globally, especially because the bacterium has developed resistance to most antimicrobials introduced for first-line treatment of gonorrhea. In the present study, 96 N. gonorrhoeae isolates with high-level resistance to penicillin from 121 clinical isolates in Thailand were examined to investigate changes related to their plasmid-mediated penicillin resistance and their molecular epidemiological relationships. A β-lactamase (TEM) gene variant, bla TEM-135 , that may be a precursor in the transitional stage of a traditional bla TEM-1 gene into an extended-spectrum β-lactamase (ESBL), possibly causing high resistance to all extended-spectrum cephalosporins in N. gonorrhoeae , was identified. Clonal analysis using multilocus sequence typing (MLST) and N. gonorrhoeae multiantigen sequence typing (NG-MAST) revealed the existence of a sexual network among patients from Japan and Thailand. Molecular analysis of the bla TEM-135 gene showed that the emergence of this allele might not be a rare genetic event and that the allele has evolved in different plasmid backgrounds, which results possibly indicate that it is selected due to antimicrobial pressure. The presence of the bla TEM-135 allele in the penicillinase-producing N. gonorrhoeae population may call for monitoring for the possible emergence of ESBL-producing N. gonorrhoeae in the future. This study identified a bla TEM variant ( bla TEM-135 ) that is a possible intermediate precursor for an ESBL, which warrants international awareness.

Many essential oils have antibacterial activity with a potential use in medicine. Citrus hystrix DC, or makrut lime, contains two essential oils, makrut leaf oil and makrut (fruit peel) oil, of which we determined the inhibitory effect against respiratory pathogens and evaluated their active components. Gas chromatography-mass spectrometry was used to analyse the chemical composition of the essential oils. The antibacterial activities were tested by disc-diffusion and broth microdilution methods against 411 isolates of groups A, B, C, F, G streptococci, Streptococcus pneumoniae, Haemophilus influenzae, Staphylococcus aureus (methicillin-resistant and -sensitive S. aureus) and Acinetobacter baumannii, obtained from patients with respiratory tract infections. Makrut leaf oil and makrut oil were both effective against all the pathogens with minimal inhibitory concentration (MIC) ranges of 0.06-68 mg/ml and 0.03-17.40 mg/ml, respectively. Citronellal was found to be the major component (80.04%) in makrut leaf oil and had the lowest MIC. In contrast, makrut oil consisted of several components (limonene 40.65%, terpinene-4-ol 13.71%, -terpineol 13.20%), and the most active component was -terpineol, followed by terpinene-4-ol, and limonene. These results suggest that makrut leaf oil, makrut oil, and their components (citronellal, -terpineol, terpinene-4-ol) may be alternative natural source medicine to prevent and treat many bacterial diseases.