When primers were applied to detect acetylation-associated genes, it was established that the primers designed to target aac (3)-I, aac (3)-II, and aac (3)-III homologues did not generate amplicons. In each of these PCR reactions the positive controls successfully amplified, thus we are satisfied that the lack of amplification products
for our metagenomic sample is a true result. However, a number of distinct aac (6) and aac (3)-VI homologues were selleck chemicals detected and were found to resemble genes from a variety of genera, including Acinetobacter, Pseudomonas and Enterobacter (Table 3). The presence of aminoglycoside acetylation genes within these genera has been noted previously [50–53]. The detection of resistance genes resembling those seen in A. baumannii is a concern, as many strains of this species have been shown to exhibit multi-drug resistance Selonsertib chemical structure [54, 55]. In addition, homologues of genes from Collinsella and Salmonella were also detected. Primers designed to amplify bifunctional aac (6′)-Ie-aph (2′) genes were also employed. Our investigations revealed the
presence of homologues of such genes, resembling those from S. aureus, E. faecium and S. epidermidis, all of which are known sources of these genes [27, 56, 57]. Table 3 Homologues of aminoglycoside resistance genes detected in the human gut microbiota via PCR techniques Accession Selleckchem Vactosertib # Gene description Closest homologue E value % identity aac (6)
AAA25680.1 AG 6′-N-acetyltransferase Pseudomonas fluorescens 4 e-48 98 WP_006234103.1 Hypothetical protein Colaer00186 Collinsella aerofaciens 0.0 95 AAS45464.1 6′-N-acetyltransferase A. baumannii 3e-33 75 aac (6′)- Ie-aph (2″) WP_002304968.1 Phosphotransferase E. faecium 9e-108 100 WP_001028140.1 Acetyltransferase GNAT S. aureus 1e-107 99 WP_001028143.1 Acetyltransferase GNAT S. aureus 1e-107 99 WP_010729367.1 Bifunctional AAC/APH partial sequence E. faecium 5e-106 99 AAX82584.1 Bifunctional AG modifying enzyme Enterococcus faecalis 2e-112 100 WP_002417297.1 6′ AG acetyltransferase E. faecalis 3e-111 97 AFR11868.1 Bifunctional AG 6′-N acetytransferase/2′-AG phosphotransferases S. epidermidis HAS1 1e-43 99 AFM29914.1 Gentamycin resistance protein Enterococcus sp. 7e-45 97 aph (2″) Id 3SG8_A Chain A crystal structure AG 2′ phosphotransferases E. casseliflavus 1e-110 98 3N4T_A Aph2″ chain a E. casseliflavus 2e-110 99 AAT77696.1 AG modifying enzyme E. faecium 1e-68 94 Aph (2″)-Ic 3TDVA AG phosphotransferase Enterococcus gallinarum 2e-83 97 ant (2″) Ia YP_005176240.1 AG 2′–O-adenyltransferase Pasturella mutocida 2e-97 100 WP_000314377.1 2′ AG nucleotidlytransferase A. baumannii 3e-94 99 WP_000946493.1 2′ AG A. baumannii 1e-94 99 ACJ47203.1 AG adenyltransferase E. coli 6e-94 99 ACA48663.14 AG adenyltransferase Morganella morganii 2e-96 99 aac (3)-VI AAA16194.