Little leaf of brinjal is one of the devastating disease effecting brinjal cultivars worldwide. So far no report is available on molecular detection and characterization of phytoplasma associated with brinjal from South India. Aims and objectives- This study was conducted to detect characterize and group phytoplasma associated with little leaf of brinjal from Karnataka. Materials and methods –Field survey was conducted to collect symptomatic, asymptomatic and healthy samples. Genomic DNA was isolated and subjected to nested PCR with universal primer pairs P1/P7 and R16nF2/R16nR2 respectively for amplification of highly conserved 16SrRNA gene. The amplified products were analyzed on 1.5% agarose gel and the expected nested PCR product of 1250 bp were purified, sequenced in both the directions by Sanger sequencing method and were assembled using Codon Code Aligner software. Multiple sequence alignment was done. Virtual RFLP pattern, restriction map was obtained and phylogenetic tree was constructed. Results and Conclusion - The nBLAST search and phylogenetic analysis of the sequence showed that, all the three samples shared maximum similarity with Clover proliferation (16SrVI) group. The virtual RFLP pattern obtained using iPhyclassifier revealed the association of a new 16SrVI subgroup phytoplasma with one isolate and 16SrVI-D group phytoplasma with other two isolates. This study reports the association of 16SrVI-D and a new sub-group phytoplasma associated with little leaf of brinjal from Karnataka.

It has been largely hypothesized, but never probed, that PBPs and β-lactamases come from an ancient common ancestor, although, there are examples of cross enzymatic reactions (DD-peptidase and β-lactamase) for both types of enzymes. This work aimed to characterize the effect of point mutations [R2→G (AmpC-F2), P243→L (AmpC-F4:C3) and I51→T (AmpC-F4:C6)] on β-lactamase activity of AmpC (Pae-AmpC) from Pseudomonas aeruginosa PAO1 strain; also to track the effect of AmpC activity on peptidoglycan composition, as a consequence of DD-peptidase activities . So, periplasmic and cytoplasmic forms of these Pae-AmpC mutants and the wild type Pae-AmpC were cloned, purified by Ni-affinity chromatography, and then tested for their β-lactamase activities and their effect on PG composition from wild type and mutants of E. coli and P. aeruginosa. In vitro assay for β-lactamase activities showed that both point mutations P243→L and I51→T caused 5-fold decrease, while R2→G change caused 2.5-fold decrease in β-lactamase activity when compared with AmpC-F4. On the other hand the cytoplasmic form (AmpC-F3) displayed 8-fold increase in β-lactamase activity. Moreover, AmpC-F3 displayed a secondary DD-endopeptidase/DD-carboxypeptidase on the whole PG in vitro, and DD-endopeptidase activity on individual purified muropeptides. Data obtained from HPLC analysis of PG composition support previous suggestions that AmpC can elicit DD-carboxypeptidase or DD-endopeptidase activity most probably due to structural similarities of the active site with DD-peptidase enzymes having these activities (LMM-PBPs).