ISOLATION, MOLECULAR CHARACTERIZATION AND ANTIBIOTICS SUSCEPTIBILITY PATTERNS OF METHYLOTROPHIC BACTERIA OCCURING IN HUMAN MOUTH

Abstract

Methylotrophic bacteria are ubiquitous bacteria that are capable of using one carbon compounds such as methane, methanol, halogenated methane, and methylated amine as sources of carbon and energy for their diverse metabolic activities. The study isolated methylotrophic bacterial isolates from the tongue, and supra- and subgingival plaque in the mouths of volunteers and patients with periodontitis. The bacteria were identified and their antibiotics susceptibility pattern evaluated before carrying out their molecular characterization from 150 volunteers and patients with periodontitis using standard methods. Nutrient agar fortified with methylamine as a growth factor was used to aid the growth of these bacterial.The results showed that a total of twelve(12) bacteria were identified. These were Bacillus licheniformis, Neisseria flava, Neisseria meningitis, Micrococcus flava, Pseudomonas aeruginosa, Streptococcus pneumoniae, Methylobacteria radiotolerance, Methylotrophic thiocynatum, Methylococcus capsulatum, Methylotrophic rubra and Branhamella catarhalis. The antibiotics susceptibility test showed that B. licheniformis, N. meningitis and P. aeruginosa exhibited the highest resistance against the antibiotics. The most susceptible bacterium was Methylobacterium radiotolerance. The antibiotics that exert the highest zone of inhibition on the bacteria wereceftiaxone and ofloxaxin, exerting a zone of inhibition of 29-10± 1.40mm diameter.The 12 bacteria were characterized molecularly with Polymerase chain reaction PCR amplified methodusing primers for the virulence genes ofMethylotroph. The mxaFgene of methanol dehy- drogenaseMxaF was detected in 3 bacterial isolates: pilc ofpilin gene in 3 bacteria,stx1 of shiga toxin.nana of neuraminidase and pila of pilin gene was detected in all the bacteria This result will assist in the design and construction of additional oligo-nucleotides probes for the determination of which methylotrophic species are present as ubiquitous members of mouth biofilm communities .The results obtained in this research showed that methylotrophs may be responsible for periodontitis and that healthy people are carriers.