Improved and contemporary agriculture relies heavily on pesticides, yet some can be quite persistent and have a stable chemical composition, posing a significant threat to the ecology. Removing harmful effects is upon their degradability. Biodegradation must be emphasized to lower pesticide degradation costs, especially in the soil. Here, a decision-making system was used to determine the best microbial strain for the biodegradation of the pyrethroid-contaminated soil. In this system, the criteria chosen as: pH (C1), Temp (C2), RPM (C3), Conc. (C4), Degradation (%) (C5) and Time required for degradation(hrs) (C6); and five alternatives were Bacillus (A1), Acinetobacter (A2), Escherichia (A3), Pseudomonas (A4), and Fusarium (A5). The best alternative was selected by applying the TOPSIS (technique for order performance by similarity to ideal solution) method, which evaluates based on their closeness to the ideal solution and how well they meet specific requirements. Among all the specified criteria, Acinetobacter (A2) was the best and optimal based on the relative closeness value (( R i ∗ ) = 0.740 (A2) > 0.544 (A5) > 0.480 (A1) > 0.403 (A4) > 0.296 (A3)). However, the ranking of the other alternatives is also obtained in the order Fusarium (A5), Bacillus (A1), Pseudomonas (A4), Escherichia (A3). Hence this study suggests Acinetobacter is the best microbial strain for biodegradation of pyrethroids; while least preference should be given to Escherichia. Acinetobacter, versatile metabolic nature with various xenobiotic compounds\' degradation ability, is gram-negative, aerobic, coccobacilli, nonmotile, and nonspore forming bacteria. Due to less study about Acinetobacter it is not in that much frame as the other microorganisms. Hence, considering the Acinetobacter strain for the biodegradation study will give more optimal results than the other microbial strains. Novelty of this study, the TOPSIS method is applied first time in selecting the best microbial strain for the biodegradation of pyrethroid-contaminated soil, considering this selection process as multi-criteria decision-making (MCDM) problem.

UNASSIGNED: Ventilator-associated pneumonia (VAP) is a nosocomial infection associated with high morbidity and mortality. This study was undertaken to monitor the trend of the demographical details, comorbid conditions, bacterial etiological agents, and their antibiogram causing VAP in adults in the year 2008, 2013 and 2018.
UNASSIGNED: A retrospective study conducted at the Department of Microbiology, Hospital Infection control and Quality Control at a tertiary care teaching hospital. All the adult patients with more than 48 h of the mechanical ventilator with endotracheal intubation with Clinical Pulmonary infection Score >6 with suspicion of VAP were included in the study at a difference of 5 years, i.e., 2008, 2013, and 2018.
UNASSIGNED: A total of 338 patients were included in the study, of which males accounted for more than two-third of the patients studied. Nearly 45% of the patients belonged to geriatric (>60 years) age group. The most common comorbid conditions were chronic obstructive pulmonary disease, hypertension and diabetes mellitus. Among the gram-negative isolates, Klebsiella pneumoniae, Acinetobacter species, and Pseudomonas aeruginosa were the most common. There is an emergence of resistance to most commonly administered antimicrobial agents like aminoglycosides, levofloxacin, piperacillin/tazobactum, and carbapenems during the study period.
UNASSIGNED: This is a ten-year study on the antibiotic resistance pattern of organisms causing VAP. As far as the authors are aware, this is the first study addressing the pattern of change in drug resistance in the organisms causing VAP over a decade. The emergence of multi-drug resistant (MDR) MDR pathogens, especially in intensive care unit (ICU), is a great concern for the intensivist and infection control physicians. Preventive measures need to be undertaken to control the spread of these pathogens to the patients in the ICU.

BACKGROUND: Acinetobacter lwoffii (A. lwoffii) is a Gram-negative bacteria common in the environment, and it is the normal flora in human respiratory and digestive tracts. The bacteria is a zoonotic and opportunistic pathogen that causes various infections, including nosocomial infections. The aim of this study was to identify A. lwoffii strains isolated from bovine milk with subclinical mastitis in China and get a better understanding of its antimicrobial susceptibility and resistance profile. This is the first study to analyze the drug resistance spectrum and corresponding mechanisms of A. lwoffii isolated in raw milk.
RESULTS: Four A. lwoffii strains were isolated by PCR method. Genetic evolution analysis using the neighbor-joining method showed that the four strains had a high homology with Acinetobacter lwoffii. The strains were resistant to several antibiotics and carried 17 drug-resistance genes across them. Specifically, among 23 antibiotics, the strains were completely susceptible to 6 antibiotics, including doxycycline, erythromycin, polymyxin, clindamycin, imipenem, and meropenem. In addition, the strains showed variable resistance patterns. A total of 17 resistance genes, including plasmid-mediated resistance genes, were detected across the four strains. These genes mediated resistance to 5 classes of antimicrobials, including beta-lactam, aminoglycosides, fluoroquinolones, tetracycline, sulfonamides, and chloramphenicol.
CONCLUSIONS: These findings indicated that multi-drug resistant Acinetobacter lwoffii strains exist in raw milk of bovine with subclinical mastitis. Acinetobacter lwoffii are widespread in natural environmental samples, including water, soil, bathtub, soap box, skin, pharynx, conjunctiva, saliva, gastrointestinal tract, and vaginal secretions. The strains carry resistance genes in mobile genetic elements to enhance the spread of these genes. Therefore, more attention should be paid to epidemiological surveillance and drug resistant A. lwoffii.

Ammonium polyphosphate (APP), a pivotal constituent within environmentally friendly flame retardants, exhibits notable decomposition susceptibility and potentially engenders ecological peril. Consequently, monitoring the APP concentration to ensure product integrity and facilitate the efficacious management of wastewater from production processes is of great significance. A fluorescent assay was devised to swiftly discern APP utilizing 4\',6\'-diamino-2-phenylindole (DAPI). With increasing APP concentrations, DAPI undergoes intercalation within its structure, emitting pronounced fluorescence. Notably, the flame retardant JLS-PNA220-A, predominantly comprising APP, was employed as the test substrate. Establishing a linear relationship between fluorescence intensity (F-F0) and JLS-PNA220-A concentration yielded the equation y = 76.08x + 463.2 (R2 = 0.9992), with a LOD determined to be 0.853 mg/L. The method was used to assess the degradation capacity of APP-degrading bacteria. Strain D-3 was isolated, and subsequent analysis of its 16S DNA sequence classified it as belonging to the Acinetobacter genus. Acinetobacter nosocomialis D-3 demonstrated superior APP degradation capabilities under pH 7 at 37 °C, with degradation rates exceeding 85% over a four-day cultivation period. It underscores the sensitivity and efficacy of the proposed method for APP detection. Furthermore, Acinetobacter nosocomialis D-3 exhibits promising potential for remediation of residual APP through environmental biodegradation processes.

The blaNDM-1 gene and its variants encode metallo-beta-lactamases that confer resistance to almost all beta-lactam antibiotics. Genes encoding blaNDM-1 and its variants can be found in several Acinetobacter species, and they are usually linked to two different plasmid clades. The plasmids in one of these clades contain a gene encoding a Rep protein of the Rep_3 superfamily. The other clade consists of medium-sized plasmids in which the gene (s) involved in plasmid replication initiation (rep)have not yet been identified. In the present study, we identified the minimal replication region of a blaNDM-1-carrying plasmid of Acinetobacter haemolyticus AN54 (pAhaeAN54e), a member of this second clade. This region of 834 paired bases encodes three small peptides, all of which have roles in plasmid maintenance. The plasmids containing this minimal replication region are closely related; almost all contain blaNDM genes, and they are found in multiple Acinetobacter species, including A. baumannii. None of these plasmids contain an annotated Rep gene, suggesting that their replication relies on the minimal replication region that they share with the plasmid pAhaeAN54e. These observations suggest that this plasmid lineage plays a crucial role in the dissemination of the blaNDM-1 gene and its variants.

Among the Acinetobacter genus, Acinetobacter pittii stands out as an important opportunistic infection causative agent commonly found in hospital settings, which poses a serious threat to human health. Recently, the high prevalence of carbapenem-resistant A. pittii isolates has created significant therapeutic challenges for clinicians. Bacteriophages and their derived enzymes are promising therapeutic alternatives or adjuncts to antibiotics effective against multidrug-resistant bacterial infections. However, studies investigating the depolymerases specific to A. pittii strains are scarce. In this study, we identified and characterized a capsule depolymerase, Dpo27, encoded by the bacteriophage IME-Ap7, which targets A. pittii. A total of 23 clinical isolates of Acinetobacter spp. were identified as A. pittii (21.91%, 23/105), and seven A. pittii strains with various K locus (KL) types (KL14, KL32, KL38, KL111, KL163, KL207, and KL220) were used as host bacteria for phage screening. The lytic phage IME-Ap7 was isolated using A. pittii 7 (KL220) as an indicator bacterium and was observed for depolymerase activity. A putative tail fiber gene encoding a polysaccharide-degrading enzyme (Dpo27) was identified and expressed. The results of the modified single-spot assay showed that both A. pittii 7 and 1492 were sensitive to Dpo27, which was assigned the KL220 type. After incubation with Dpo27, A. pittii strain was susceptible to killing by human serum; moreover, the protein displayed no hemolytic activity against erythrocytes. Furthermore, the protein exhibited sustained activity across a wide pH range (5.0-10.0) and at temperatures between 20 and 50°C. In summary, the identified capsule depolymerase Dpo27 holds promise as an alternative treatment for combating KL220-type A. pittii infections.

The genus Acinetobacter comprises both environmental and clinically relevant species associated with hospital-acquired infections. Among them, Acinetobacter baumannii is a critical priority bacterial pathogen, for which the research and development of new strategies for antimicrobial treatment are urgently needed. Acinetobacter spp. produce a variety of structurally diverse capsular polysaccharides (CPSs), which surround the bacterial cells with a thick protective layer. These surface structures are primary receptors for capsule-specific bacteriophages, that is, phages carrying tailspikes with CPS-depolymerizing/modifying activities. Phage tailspike proteins (TSPs) exhibit hydrolase, lyase, or esterase activities toward the corresponding CPSs of a certain structure. In this study, the data on all lytic capsule-specific phages infecting Acinetobacter spp. with genomes deposited in the NCBI GenBank database by January 2024 were summarized. Among the 149 identified TSPs encoded in the genomes of 143 phages, the capsular specificity (K specificity) of 46 proteins has been experimentally determined or predicted previously. The specificity of 63 TSPs toward CPSs, produced by various Acinetobacter K types, was predicted in this study using a bioinformatic analysis. A comprehensive phylogenetic analysis confirmed the prediction and revealed the possibility of the genetic exchange of gene regions corresponding to the CPS-recognizing/degrading parts of different TSPs between morphologically and taxonomically distant groups of capsule-specific Acinetobacter phages.

BACKGROUND: Acinetobacter lwoffii (A.lwoffii) is a serious zoonotic pathogen that has been identified as a cause of infections such as meningitis, bacteremia and pneumonia. In recent years, the infection rate and detection rate of A.lwoffii is increasing, especially in the breeding industry. Due to the presence of biofilms, it is difficult to eradicate and has become a potential super drug-resistant bacteria. Therefore, eradication of preformed biofilm is an alternative therapeutic action to control A.lwoffii infection. The present study aimed to clarify that baicalin could eradicate A.lwoffii biofilm in dairy cows, and to explore the mechanism of baicalin eradicating A.lwoffii.
RESULTS: The results showed that compared to the control group, the 4 MIC of baicalin significantly eradicated the preformed biofilm, and the effect was stable at this concentration, the number of viable bacteria in the biofilm was decreased by 0.67 Log10CFU/mL. The total fluorescence intensity of biofilm bacteria decreased significantly, with a reduction rate of 67.0%. There were 833 differentially expressed genes (367 up-regulated and 466 down-regulated), whose functions mainly focused on oxidative phosphorylation, biofilm regulation system and trehalose synthesis. Molecular docking analysis predicted 11 groups of target proteins that were well combined with baicalin, and the content of trehalose decreased significantly after the biofilm of A.lwoffii was treated with baicalin.
CONCLUSIONS: The present study evaluated the antibiofilm potential of baicalin against A.lwoffii. Baicalin revealed strong antibiofilm potential against A.lwoffii. Baicalin induced biofilm eradication may be related to oxidative phosphorylation and TCSs. Moreover, the decrease of trehalose content may be related to biofilm eradication.

The emergence of antibiotic resistance in Acinetobacter spp. is a rising public health concern worldwide. The objective of this study was to investigate the prevalence of antibiotic-resistance genes and the virulence of Acinetobacter spp. isolated from soil and crops obtained from agricultural fields in South Korea. Eight Acinetobacter spp. isolates carried various antibiotic resistance genes, such as emrAB (100%), cat/craA (100%), and aadA gene (87.5%). Minimum inhibitory concentration (MIC) analysis revealed that strains harboring antibiotic resistance genes exhibited high resistance to the respective antibiotics, such as colistin, chloramphenicol, and streptomycin. Interestingly, most of these isolates had high capability of biofilm formation and swarming motility, along with faster growth rates. Taken together, our study demonstrated that antibiotic-resistant Acinetobacter isolated from agricultural settings in South Korea not only frequently carries antibiotic resistance genes but also has virulence-related traits.
UNASSIGNED: The online version contains supplementary material available at 10.1007/s10068-023-01496-7.

Globally, drought stress poses a significant threat to crop productivity. Improving the drought tolerance of crops with microbial biostimulants is a sustainable strategy to meet a growing population\'s demands. This research aimed to elucidate microbial biostimulants\' (Plant Growth Promoting Rhizobacteria) role in alleviating drought stress in oil-seed crops. In total, 15 bacterial isolates were selected for drought tolerance and screened for plant growth-promoting (PGP) attributes like phosphate solubilization and production of indole-3-acetic acid, siderophore, hydrogen cyanide, ammonia, and exopolysaccharide. This research describes two PGPR strains: Acinetobacter calcoaceticus AC06 and Bacillus amyloliquefaciens BA01. The present study demonstrated that these strains (AC06 and BA01) produced abundant osmolytes under osmotic stress, including proline (2.21 and 1.75 µg ml- 1), salicylic acid (18.59 and 14.21 µg ml- 1), trehalose (28.35 and 22.74 µg mg- 1 FW) and glycine betaine (11.35 and 7.74 mg g- 1) respectively. AC06 and BA01 strains were further evaluated for their multifunctional performance by inoculating in Arachis hypogaea L. (Groundnut) under mild and severe drought regimes (60 and 40% Field Capacity). Inoculation with microbial biostimulants displayed distinct osmotic-adjustment abilities of the groundnut, such as growth parameters, plant biomass, photosynthetic pigments, relative water content, proline, and soluble sugar in respective to control during drought. On the other hand, plant sensitivity indexes such as electrolyte leakage and malondialdehyde (MDA) contents were decreased as well as cooperatively conferred plant drought tolerance by induced alterations in stress indicators such as catalase (CAT), ascorbate peroxidase (APX), and superoxide dismutase (SOD). Thus, Acinetobacter sp. AC06 and Bacillus sp. BA01 can be considered as osmolyte producing microbial biostimulants to simultaneously induce osmotic tolerance and metabolic changes in groundnuts under drought stress.