Mutations in the 23S rRNA Gene of Helicobacter pylori Associated with Clarithromycin Resistance

Abstract

Among 12 clarithromycin-resistant Helicobacter pylori strains isolated in Guri, Korea,8 showed an adenine to guanine mutation at position 2143 (formerly A2144G or E. coli 2059) in the 23S rRNA gene by the PCR-restriction fragment length polymorphism (RFLP) method. The remaining 4 strains, digested by neither BsaI nor BbsI, showed a thymine to cytosine mutation at position 2182 (T2182C) by direct sequencing of the PCR products. The T2182C mutants showed a tendency of higher levels of minimum inhibitory concentration to clarithromycin than the A2143G mutants. In conclusion, either the A2143G or the T2182C mutation was present in 100% of clarithromycin-resistant H. pylori isolates examined. The PCR-RFLP technique with restriction enzymes BbsI and BsaI was a rapid and relatively simple method to detect the clarithromycin resistance. But undigested isolates were quite frequent among our isolates (33.3%), the PCR-RFLP method with restriction enzymes BbsI and BsaI should not be used alone, and development of other rapid detection method for clarithromycin resistance is mandatory.

T2182C Mutation Is Not Associated with Clarithromycin Resistance in Helicobacter pylori

“…Mutations at other positions or no mutation in the 23S rRNA has also been associated with different levels of Cla r . We would like to respond to points raised by Burucoa et al The association of the T2182C mutation and Cla r was first reported by Kim et al (7), and in our study we confirmed the earlier finding by transformation and sequencing of 23S rRNA from single-colony isolates. It is apparent from the letter that Burucoa et al performed all of their initial analysis (isolation, MIC determination, DNA extraction, PCR, sequencing, and transformation) with pooled isolates and subsequently realized that they were working with mixed isolates.…”

Determinación de mutaciones de un solo nucleótido en el gen 23S rRNA de Helicobacter pylori relacionadas con resistencia a claritromicina en una población del departamento del Cauca, Colombia

“…La frecuencia de H. pylori con mutaciones resistentes a la claritromicina varía entre áreas geográficas: en Estados Unidos, entre 48 y 53 % porta la mutación A2142G; en Europa se ha reportado entre 23 y 33 % para A2142G, 44 y 67 % para A2143G y para A2142C, de 2 a 10 %. Algunos estudios en Japón demuestran que más de 90 % de las mutaciones tiene el genotipo A2143G y en China indican que 100 % de ellas es A2143G (19,22).…”

“…El juego de iniciadores amplifica un fragmento de 425 pb en donde se ubican las mutaciones de las posiciones 2142, 2143, 2144. Se usaron los iniciadores previamente reportados por Occhialini, et al, para la amplificación de esta región: K1 (5'-CCA CAG CGA TGT GGT CTC AG-3', complementaria a la posición 2191 a 2210) y K2 (5'CTC CAT AAG AGC CAA AGC CC-3', complementaria a la posición 2596 a 2615) (19 Los productos de amplificación de 425 pb se evidenciaron en geles de agarosa al 2 % por tinción con bromuro de etidio bajo luz ultravioleta y por comparación con la banda de amplificación de la cepa NCTC 11637 de H. pylori. Como control de calidad, los productos de PCR (425 pb) se purificaron para eliminar restos de cebadores, de dNTP y de enzimas que pudiesen causar ruido de fondo en las secuencias.…”

T2182C Mutation in 23S rRNA Is Associated with Clarithromycin Resistance in Helicobacter pylori Isolates Obtained in Bangladesh

“…Alteration in either one or both copies of the H. pylori 23S rRNA gene is associated with resistance to clarithromycin, and the mechanism is a point mutation (an adenine-to-guanine transition at either position 2142 or 2143 or an adenine-to-cytosine transversion at position 2142) of the 23S rRNA (2,8,15,18,19,23). However, a T2182C mutation has also been proposed to be associated with clarithromycin resistance (10). In the present study we have examined clarithromycin-resistant (Cla r ) H. pylori (CRHP) isolates and characterized a T2182C mutation involved in clarithromycin resistance.…”