Shiga-like toxin (Stx) is an important factor in the pathogenesis of Escherichia coli O157:H7 infection and is responsible for some severe complications. Stx2 is usually associated with hemolytic uremic syndrome in humans. Its expression is regulated by elements located upstream of the stx2 gene, including stx2-promoter sequence, ribosome binding site, and the antiterminator q gene. The present study aimed to find the correlation between regulatory elements and the expression level of Stx2 in two local isolates of E. coli O157:H7. Two local E. coli O157:H7 strains SM-25(1) and KL-48(2), originating from human and cattle feces, respectively, and an E. coli reference strain, ATCC 43894, were investigated. The complete stx2 gene covering the sequences of promoter, ribosome binding site, and open reading frame and q gene of each strain was analyzed. The magnitude of Stx2 production was detected with a reverse passive latex agglutination method and Stx mediated cellular damage was determined with the Vero cell assay. A comparison of the complete stx2 gene contained stx2-promoter, ribosome binding site, and q genes of two local strains KL-48(2) and SM25(1), and the E. coli ATCC 43894 showed that the amino acid sequences were identical. Both local isolates were Stx negative in the reverse passive latex agglutination test and nontoxic in the Vero cell assay. The expression level of Shiga-like toxin of the two local isolates of E. coli O157:H7 did not only depend on the regulatory elements of the stx2 gene.

ObjectiveTo evaluate the zoonotic potency of Escherichia coli O157:H7 through arbitrarily primed-PCR (AP-PCR) methods as one of the DNA fingerprinting methods.MethodsA total of 14 isolates consisted of 11 isolates originated from human feces with renal failure symptoms, 2 isolates originated from cattle feces, and 1 control isolate were used in this study. DNA of each isolate was extracted, and their profiles were studied by using AP-PCR method with M13 F and M13 R arbitrary primers.ResultsThe results founded that all of 14 isolates had similarity range from 54.6% to 88.5%. Isolates KL-106(3) and KL-55(6) originated from humans showed the degree of similarity with isolates SM-25(1) and SM-7(1) originated from cattle as high as 85% and 77%, respectively.ConclusionsThe high degree of similarity between isolates originated from cattle and human indicated the high potency of zoonoses. The results also concluded AP-PCR method as a briefly fingerprinting method in order to trace the epidemiological of E. coli O157:H7

Background and Aim: The nasal cavity of a pig serves as an entry point and a habitat for the colonization of commensal microbes and pathogenic bacteria. Based on biochemical and serological tests, Streptococcus β-hemolytic Group C was identified as the Gram-positive bacteria, which resulted in the 1994 outbreak and death of thousands of pigs in Bali. Furthermore, this agent is zoonotic and frequently results in the development of meningitis lesions in the infected pig. Recently, a meningitis outbreak in humans was also reported after the consumption of pig-derived foods at Sibang Kaja, Badung-Bali. This study aimed to identify and characterize Gram-positive β-hemolytic organisms collected from nasal swab of pigs from the outbreak area, as well as to compare API Kit and 16S rRNA gene analysis methods. Materials and Methods: This study commenced with the cultivation of two isolates, Punggul Swab Nasal (PSN) 2 and PSN 19, which were characterized by β-hemolysis activity. These samples were then conventionally and molecularly identified using Kit API 20 Strep and 16S ribosomal RNA (rRNA) gene primers, respectively. Results: Using the Kit API 20 Strep, both isolates were identified as Enterococcus faecium, which was previously classified as Group D Streptococci. Based on the 16S rRNA gene sequencing, PSN 2 and PSN 19 were molecularly confirmed to have 99 and 98.1% similarities with E. faecium (NR042054), respectively. Furthermore, both isolates share the same clade in the phylogenetic tree analysis. Conclusion: Using Kit API 20 Strep and 16S rRNA gene analysis, the PSN 2 and PSN 9 Gram-positive isolates with β-hemolysis activity from pig nasal swabs were identified as E. faecium.

Lactic acid bacteria are the type of bacteria that has benefits in food and health industries as a biopreservative, fermentative, or probiotics. Bali cattle are known as potential host for specific lactic acid bacteria. The aim of this study is to identify phenotypically lactic acid bacteria 9A isolated from bali cattle’s colon, that producing a substance which known has potency as antimicrobial. In this study, phenotypic identification included conventional method and API 50 CHL. The result of this study showed that lactic acid bacteria isolate 9A was Streptococcus sp., whereas identification by kit API 50 CHL showed isolate 9A as Lactobacillus fermentum with 83% identity. The difference between the results of conventional method and kit API 50 CHL, may indicate the difference in sensitivity and specificity of the two methods, hence it needs further confirmation.

An antigen will be able to stimulate an immune response if the antigen has been presented and recognized by T-cells. Major Histocompatibility Complex (MHC) molecules are molecules that will recognize and present the peptides of the antigen. In humans, two classes of MHC are known to carry out this role, namely Class-I MHC and Class-II MHC, while Class-III MHC has a function that is not directly related to peptide binding. The genes that code for MHC molecules are so polymorphic that each individual is certain to have a different allele (heterozygous). In Class-I MHC, only the α-chain is polymorphic while in Class-II MHC both α and β-chains are polymorphic. MHC polymorphism will affect (1) the ability to create immune responses including antibody production, (2) resistance or susceptibility to infectious diseases, and (3) resistance or susceptibility to autoimmune and allergic diseases. That is why MHC is so polymorphic. The immune system has to fight many different pathogens. By having many different MHC molecules, one can present widely different antigens and can spur an effective immune response.

Backgrounds: Pseudomonas aeruginosa can form a biofilm in less than 24 hours that is resistant to antibiotics. The pslA gene is exopolysaccharides involved in biofilm formation. Biofilm formed by pslA gene can increase opportunity for acquired resistance mechanisms to occur due to gene transfer between bacteria in the biofilm. This study purpose is to determine the prevalence of pslA gene in MDR and non-MDR P. aeruginosa clinical isolates at Prof. Dr. I.G.N.G. Ngoerah for period July 2022 - June 2023. Methods: This research is qualitative descriptive study to determine the presence of pslA gene which detected using PCR method. Samples were taken using cross-sectional technique, available clinical isolates for period July 2022 - June 2023 at RSUP Prof. Dr. I.G.N.G. Ngoerah, with identification test VITEK-2 Compact and probability level ≥90%. Obtained data were analyzed descriptively by grouping based on research variables in the form of frequency distribution table. Results: pslA gene is detected in 37 (88,09%) P. aeruginosa isolates, with 19 (90,47%) among them in MDR isolates, and 18 (85,71%) in non-MDR isolates. Conclusion: pslA gene is found in MDR and Non-MDR P. aeruginosa isolates. Latar Belakang: Pseudomonas aeruginosa membentuk biofilm kurang dari 24 jam yang resistan antibiotik. Gen pslA merupakan eksopolisakarida yang terlibat dalam pembentukan biofilm. Dengan adanya biofilm yang terbentuk oleh gen pslA dapat meningkatkan kesempatan terjadinya acquired resistance mechanisms akibat transfer gen antarbakteri dalam biofilm. Penelitian ini bertujuan mencari prevalensi gen pslA pada isolat klinis P. aeruginosa MDR dan non-MDR di RSUP Prof. Dr. I.G.N.G. Ngoerah Periode Juli 2022 - Juni 2023. Metode: Penelitian adalah deskriptif kualitatif untuk mengetahui keberadaan gen pslA yang terdeteksi menggunakan metode PCR. Sampel penelitian diambil dengan teknik cross-sectional, yaitu isolat klinis yang tersedia selama periode Juli 2022 - Juni 2023 di Laboratorium Mikrobiologi RSUP Prof. Dr. I.G.N.G. Ngoerah, dengan tes identifikasi VITEK-2 Compact dan tingkat probabilitas identifikasi bakteri ≥90%. Data yang didapatkan dianalisis secara deskriptif dengan dikelompokkan berdasarkan variabel penelitian dalam bentuk tabel distribusi frekuensi. Hasil: Terdeteksi gen pslA pada 37 (88,09%) isolat P. aeruginosa, dengan 19 (90,47%) diantaranya isolat MDR dan 18 (85,71%) pada isolat non-MDR. Kesimpulan: Bakteri P. aeruginosa terdeteksi pada isolat klinis dari pasien di RSUP Prof. Dr. I.G.N.G. Ngoerah. Gen pslA ditemukan pada isolat P. aeruginosa MDR dan non-MDR.