GENOTYPING OF QUORUM SENSING AND BIOFILM VIRULENCE FACTORS GENES IN LOCAL ISOLATES OF ACINETOBACTER BAUMANNII

Abstract

Objective: The current investigation focused on Acinetobacter baumannii (A. baumanni), due to its growing significance as a hospital infection-causing pathogen and its resistance to several medications.

Material and Method: Sixty-five isolates of A. baumannii were isolated from wound samples of patients admitted to different hospitals in Baghdad between January and April of 2023. Two types of methods were used in the detection of biofilm formation: the first one was Congo red agar method and the second one was microtiter plate method. Genotypic detection of various virulence factors associated with A. baumannii was performed using monoplex, multiplex, and ERIC-PCR.

Result and Discussion: To use the PCR method to examine virulence genes like biofilm and quorum sensing (QS). The genes responsible for biofilm formation were identified by the PCR method, followed by ompA 63/65 (96.92%) and bap 48/65 (73.84%), whereas the genes responsible for chemical signals were found to be rhlI 43/65 (66.15%), LasI 58/65 (89.23%), LasR 56/65 (86.15%), and rhlR was 39/65 (60%) after quorum sensing (QS) system genes. ERIC-DNA fingerprinting's phylogenetic analysis illustrated the variety of all isolates by utilizing the Dice coefficient and the UPGM of phylogenetic analysis. Based on statistical analysis, the ERIC-PCR genotyping method correlation coefficient with the study virulence genes, antibiotic sensitivity test, and other variables of virulence was significant at p <0.05.

Keywords

• Acinetobacter baumannii
• biofilm formation
• multidrug resistance
• virulence factors

YEREL ACİNETOBACTER BAUMANNİİ İZOLATLARINDA ÇOĞUNLUĞU ALGILAMA VE BİYOFİLM İLE İLİŞKİLİ VİRÜLANS GENLERİNİN GENOTİPLENDİRİLMESİ

Abstract

Amaç: Mevcut araştırma, hastane enfeksiyonuna neden olan patojen olarak artan önemi ve çeşitli ilaçlara karşı direnci nedeniyle Acinetobacter baumannii (A. baumanni) üzerine odaklanmıştır. 

Gereç ve Yöntem: Ocak-Nisan 2023 tarihleri arasında Bağdat'taki farklı hastanelere başvuran hastaların yara örneklerinden altmış beş A. baumannii izole edilmiştir. Biyofilm oluşumunun tespitinde iki tür yöntem kullanılmıştır: Birincis Kongo kırmızısı agar yöntemi ve ikincisi mikrotitre plaka yöntemi. A. baumannii’ ye ait ait çeşitli virülans faktörlerinin genotipik tespiti monopleks, multipleks ve ERIC-PCR kullanılarak gerçekleştirilmiştir.

Sonuç ve Tartışma: PCR yöntemiyle biyofilm ve çoğunluğu algılama (quorum sensing; QS) ilişkili virülans genleri incelenmiştir. Biyofilm oluşumundan sorumlu genlerden ompA 63/65 (%96.92) ve bap 48/65 (%73.84) oranında tespit edilmiştir. Kimyasal sinyal mekanizmalarından sorumlu çoğunluğu algılama genlerinde ise rhlI 43/65 (%66.15), LasI 58/65 (%89.23), LasR 56/65 (%86.15) ve rhlR 39/65 (%60) bulunmuştur. ERIC-DNA parmak izi analizi, Dice katsayısı ve UPGMA filogenetik analiz yöntemiyle izolatların çeşitliliğini göstermiştir. İncelenen türler iki ayrı kümeye (A ve B) ayrılmıştır. İstatistiksel analizlere göre ERIC-PCR genotiplendirme yönteminin virülans genleri, antibiyotik duyarlılık testi ve diğer virülans değişkenleriyle korelasyon katsayısı anlamlı bulunmuştur (p < 0.05).

Keywords

• Acinetobacter baumannii
• biyofim oluşumu
• çoklu ilaç direnci
• virülans faktörleri

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