Table 2 Occurrence and prevalence of class 1 integron in Gram-positive microorganisms

1998

Corynebacterium glutamicum

First class 1 integron evidence in G⁺ microorganisms

InCg on pCG4 (29-kb), identical to InC on pSA1700

[42]

1999

Enterococcus faecalis

First class 1 integron report within Enterococcus and the species of E. faecalis

aadA was found via hotizontal transfer between E. faecalis

[43]

2002

Corynebacterium glutamicum

On pTET-3 (27.8-kb), with a novel aadA9 detected

2001–2004

Enterococcus faecalis

First class 2 integron evidence in G⁺ microorganisms and first report of class 1 integron on the species of E. Faecium

Three arrays (dfrA12-orfF-aadA2, dfrA17-aadA5 and aadA2) for class 1 integron and array dfrA1-sat1-aadA1 for class 2 integron

[44]

Enterococcus faecium

2001–2002

Streptococcus

First class 1 integron report within Streptococcus

Array of dfrA12-orfF-aadA2 detected

[44]

2004

Corynebacterium ammoniagenes

First class 1 integron report on Aerococcus spp. and the species of, C. ammoniagenes, C. casei, Brevibacterium thiogenitalis; also the first identification of class 1 integron from envirnmental G⁺ microorganisms

Such integrons carried various antibiotic resistance genes and may serve as the potentially large reservior of class 1 integron

[36]

Corynebacterium casei

Corynebacterium glutamicum

Aerococcus

Brevibacterium thiogenitalis

Staphylococcus

2001–2006

Staphylococcus aureus

First class 1 integron evidence from clinical G⁺ microorganisms from a large scale and a long study duration; first class 1 integron identification from clinical S. aureus and the species of S. epidermidis, S. haemolyticus, S. hominis and S. warneri

Typically class 1 integrons were observed, with intI1 and 3′CS of ∆qacE, a sulI gene and ORF5. Four arrays (dfrA12-orfF-aadA2, dfrA17-aadA5, aacA4-cmlA1 and aadA2) detected

[3]

Staphylococcus epidermidis

Staphylococcus haemolyticus

Staphylococcus hominis

Staphylococcus warneri

2009

Staphylococcus epidermidis

With 78 % homologous int1 and the cassette arrays of aac6

[45]

2013

Staphylococcus aureus

First class 1 integron report on the species of S. saprophyticus

With identification rate of class 1 integron as 40.5 % (81/200)

[46]

Staphylococcus epidermidis

Staphylococcus saprophyticus