L-ascorbic acid (Vitamin C, AsA) is an important component of human nutrition. Plants and several animals can synthesize their own ascorbic acid, whereas humans lack the gene essential for ascorbic acid biosynthesis and must acquire from their diet. In the present study, we developed transgenic potato (Solanum tuberosum L. cv. Taedong Valley) over-expressing L-gulono-gamma-lactone oxidase (GLOase gene; NCBI Acc. No. NM022220), isolated from rat cells driven by CaMV35S constitutive promoter that showed enhanced AsA accumulation. Molecular analyses of four independent transgenic lines performed by PCR, Southern and RT-PCR revealed the stable integration of the transgene in the progeny. The transformation frequency was ca. 7.5% and the time required for the generation of transgenic plants was 6-7 weeks. Transgenic tubers showed significantly enhanced AsA content (141%) and GLOase activity as compared to untransformed tubers. These transgenics were also found to withstand various abiotic stresses caused by Methyl Viologen (MV), NaCl or mannitol, respectively. The T(1) transgenic plants exposed to salt stress (100 mM NaCl) survived better with increased shoot and root length when compared to untransformed plants. The elevated level of AsA accumulation in transgenics was directly correlated with their ability to withstand abiotic stresses. These results further demonstrated that the overexpression of GLOase gene enhanced basal levels of AsA in potato tubers and also the transgenics showed better survival under various abiotic stresses.

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Ocular infections are common and vary from self-limiting to sight-threatening. All the structures of the eye can be infected by various microbes.The present study was undertaken to determine the prevalence of bacterial and fungal infections of the eye and also to assess the antibiotic susceptibility pattern of bacterial isolates at an eye care hospital in Bangalore, India. Material and Methods:Two hundred thirty five samples were received from infections of the eye-conjunctivitis including dacrocystis, corneal ulcers, endophthalmitis and post-traumatic infections. Culture, Gram's stain and potassium hydroxide (KOH) mount was done for allclinical specimens. Giemsa staining was done occasionally as required. Antibiotic susceptibility testing was performed for bacterial growth.Results: Out of 235 samples processed, 81(34.5%) yielded bacterial growth and 32 (13.6%) yielded fungal growth. One corneal scraping showed the presence of Acanthamoeba by microscopy. Predominant bacterial isolates wereStaphylococcus species 36 (39.9%), Pseudomonas species 20 (22.2%) and Escherichia coli 12 (13.3%). Among 25 fungal isolates, Aspergillus flavus 11(44%) and Fusarium 8 (32%) predominated. Bacterial strains were sus ceptible to gatifloxacin (86.4%), tetracycline (65.4%), chlorampenicol (69.1%) and least sensitive to the beta-lactam group like amoxicillin (23.5%). Conclusion:Conjunctival specimens yielded mainly bacterial growth with Staphylococcus species being the predominant isolate followed by Pseudomonas species. Maximum fungal isolates were from corneal scrapings with Aspergillus flavus and Fusarium being predominant. Majority of the bacteria were susceptible to gatifloxacin.

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