Relationship between Biofilm Regulating Operons and Various Β-Lactamase Enzymes: Analysis of the Clinical Features of Infections caused by Non-Fermentative Gram-Negative Bacilli (Nfgnb) from Iran

Abstract

Bacteria are capable of evolving high doses of the drug in various infections by forming biofilms. Perhaps, biofilm regulator genes have different frequencies in β-lactam producing non-fermentative Gram-negative Bacilli (NFGNB). In this study, we investigated the role of biofilm operons of Pseudomonas aeruginosa and Acinetobacter baumannii on the prevalence of different β-lactamase enzymes. One-hundred twenty (120) nosocomial NFGNB isolates were collected from different clinical samples of patients. PCR method was used for the amplification of resistance genes. Isolates were collected, including 50 isolates (41.66%) of P. aeruginosa and 70 isolates (58.33%) of A. baumannii. The distribution of ESBL, AmpC, KPC, and MBL β-lactamase enzymes in P. aeruginosa and A. baumannii isolates were 64%, 58%, 38%,44%, and 57.14%, 60%, 32.85%, 34.28%, respectively. The frequency of csuABC, pgaABC operon in A. baumannii were as follows: pgaA (45.71%), pgaB (32.85%), pgaC (42.85%), csuA (34.28%), csuB (32.85%), csuC (41.42%), and ompA (38.57%). Further, the prevalence of pslABC and pelABC operons in P. aeruginosa isolates were as follows: pslA (58%), pslB (58%), pslD (60%), pelA (64%), pelB (38%), pelC (44%), and algD (68%). This study revealed that the abundance of biofilm regulator genes in NFGNB strains is affected by different β-lactamase enzymes.

High prevalence of multidrug-resistant non-fermentative Gram-negative bacilli harboring bla and bla metallo-beta-lactamase genes in Birjand, south-east Iran

“…A similar pattern of results was obtained in many studies, which reported a high frequency of MDR and XDR strains in NFGNBs, especially among A. baumannii isolates ( 23 , 27 – 29 ). In contrast to our findings, some studies reported the different prevalence of MDR and XDR strains in NFGNBs ( 5 , 6 , 21 , 30 ). This difference could be attributed to factors such as geographical area, type of patients, hospitalization status, and history of antibiotic use.…”

“…Ever-increasing resistance to trimethoprim/sulfamethoxazole in S. maltophilia isolates has been reported interestingly in some studies ( 22 , 24 – 26 ), and the emergence of resistance to this antibiotic, as the firstline therapy for S. maltophilia infection, threatens the treatment of infections caused by them. Overall, the increasing emergence of antibiotic resistance in NFGNB isolates is a serious problem in developing countries, especially because of the relatively easy access to over-the-counter antibiotics ( 2 , 21 ).…”

Assessing the Involvement of Selected Phenotypes of Pseudomonas simiae PICF7 in Olive Root Colonization and Biological Control of Verticillium dahliae

“…In silico analysis of the PICF7 genome revealed the presence of different gene clusters presumably involved in biofilm formation such as pelABCDEFG, pslADEFGHJKL and pgaABD [ 14 ]. The implication of pel , psl and pga genes in biofilm-forming bacteria has been described elsewhere [ 59 , 60 , 61 , 62 ]. However, mutants Bfm8 and Bfm9 here reported were disrupted in genes other than the previous ones, unveiling that additional loci in the PICF7 genome are relevant for biofilm formation.…”

High Incidence of MDR and XDR Pseudomonas aeruginosa Isolates Harboring blaGES, blaVEB, and blaPER Extended-Spectrum Beta-Lactamase Genes in Iran

“…Similar an-timicrobial resistance patterns have been reported for P. aeruginosa in previous studies [19][20][21] . The ever-increasing incidence of antibiotic resistance in P. aeruginosa isolates has become a global health concern, especially in developing countries, which could be due to the relatively high level of over-the-counter antibiotic sales and frequent self-medication with antibiotics [19,22] . The findings indicated that the prevalence rate of MDR and XDR P. aeruginosa isolates was 60.8 and 53.3%, respectively.…”