Background Enterococci are nosocomial pathogen. They can develop high-level resistance to aminoglycoside by producing aminoglycoside modifying enzymes (AMEs). In enterococci, high level resistance to aminoglycosides is mediated by acquisition of plasmid mediated genes encoding for aminoglycoside modifying enzymes (AMEs). High level gentamicin resistance (MIC ≥ 500μg /mL) is predominantly mediated by aac(6′)-Ie-aph(2″)-Ia, encoding the bifunctional aminoglycoside modifying enzyme AAC(6′)-APH(2″). This enzyme eliminates the synergistic activity of gentamicin when combined with a cell wall active agent. Other AME genes such as aph(2″)-Ib, aph(2″)-Ic, aph(2″)-Id and ant(4′)-1a have also been detected in enterococci. Objective This study was carried out to determine the diverse prevalence of AME and their pattern of occurrence in the clinical isolates of Enterococci. Materials and Methods A total number of 150 clinical isolates were included in this study. Susceptibility to various antibiotics was determined by disc diffusion. Minimum Inhibitory Concentration (MIC) was ascertained by agar dilution method. Polymerase chain reaction was done to screen the following AMEs (aac(6′)-Ie-aph(2″)-Ia; aph(2″)-Ib; aph(2″)-Ic; aph(2″)-Id and aph(3′)- IIIa genes). Results 51.3% of the study isolates exhibited high level gentamicin resistance. Polymerase chain reaction revealed that aph(3′)-111a is the most prevalent AME, followed by aac(6′)-1e-aph(2″)-1a. The combination of both the genes were detected in 44.1% of the study isolates. The rest of the AMEs and their combinations were not encountered in this study. 8.6% of the study isolates did not harbour any AME genes screened for, but was phenotypically resistant to gentamicin. In contrast 31.3% anchored the AME genes but phenotypically appeared susceptible to gentamicin. Conclusion This study indicates the high- level aminoglycoside resistance disseminated among Enterococci in our geographical region. It also emphasizes the detection of AMEs by PCR is mandatory because strains that appear susceptible by disc diffusion and/or MIC method may harbour one or more AMEs genes leading to therapeutic failure.

Pulmonary infections are the most common clinical manifestations of Nocardia species. There is an increase in cases of nocardial infections occurring worldwide attributable to the increase in the immunosuppressed population. The availability of molecular methods has aided the detection of more number of cases as well as unusual species. Still, it remains one of the most underdiagnosed pathogens. Recognition of drug resistance in this organism has now mandated early and precise identification with speciation for effective treatment and management. Nocardial species identity can predict antimicrobial susceptibility and guide clinical management. Here, we report two cases of pulmonary nocardiosis caused by unusual species of Nocardia, namely, N. cyriacigeorgica and N. beijingensis identified by 16S rRNA gene-based sequencing. These cases are being reported for their rarity.

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Clustered Regularly Interspaced Short Palindromic Repeats or CRISPR‐associated protein 9 (CRISPR‐Cas9) is a genome editing tool that can remove, modify, or add sections of DNA. It is made up of two main molecules: the Cas9 protein and the guide‐RNA (gRNA), which is used to match a target gene to the CRISPR‐Cas9 molecule. The desired sequence of DNA must be between 2 and 5 nucleotides and must be followed by the protospacer adjacent motif (PAM) at the 3’ end of the gRNA. This enables the target gene to be found and cut by the Cas9 endonuclease. Once cut, the DNA can be repaired using non‐homologous end joining (where a random insertion or deletion of DNA occurs) or homology directed repair (where a homologous piece of DNA is used as a template to repair the DNA). The latter is used for genome editing, as the target sequence can be changed with the CRISPR‐Cas9 system. Sickle Cell Disease (SCD) is an autosomal recessive hereditary disorder that affects erythrocytes and is caused by a single base substitution of adenine to thymine on the hemoglobin beta (HbB) gene. Currently two different groups are examining two different techniques to treat SCD. One group has shown that by deleting the BCL11A gene, fetal hemoglobin production can occur, which greatly diminishes the amount of Sickle hemoglobin (HbS). An example of this application of CRISPR‐Cas9 for treating SCD is the story of Victoria Gray, the first person to have received genome editing treatment for SCD.