Total RNA was isolated by TRIzol method using the manufacturer’s protocol. Briefly, medium was removed, from 35mm dish and 1ml to TRIzol was added directly to the dish and kept at room temperature for 5 minutes. The cells were harvested by pipetting up and down three four times and transferred to a 1.5ml microfuge tube. For each 1mlTRIzol, 200μl of chloroform was added and tubes were shaken vigorously for 10 seconds to completely dissociate the nucleoprotein complexes, followed by vortexing for about 30 seconds. The mixture was kept for 3-5 minutes at room temperature and then centrifuged at maximum speed for 10 minutes. The upper aqueous phase was transferred into a fresh microcentrifuge tube and 500 μl of isopropanol was added and this was incubated at -20°C for 1 hour. The RNA was pelleted by centrifugation at maximum speed for 30 minutes at 4°C. The supernatant was decanted and the pellet washed with 1ml of 70% ethanol followed by a second wash with 1ml of 90% ethanol and centrifugation at maximum speed for 10 minutes. The supernatant was removed and the pellet air-dried for about 5 minutes and re-solubilized in 30-50 μl RNase free deionized (DEPC-treated Milli-Q) water and aliquots were stored at -70°C

Native isoelectric focusing was done using Pharmacia Phast Gel Apparatus and precast IEF gel (pH 3-9) from GE healthcare. The samples were prepared in 50 mM sodium buffer (pH 8.0) and applied in the middle portion of the gel. Gels were run as previously described(Olsson et al., 1988) that is at 15°C, pre-focusing at 2000 V (75Vh), sample loading at 200V (15Vh) and run at 2000V (500Vh). Staining was done using Coomassie Blue G-250

For determiningthe intracellular pH from fluorescence intensity values of CFDA-SE-loaded cells, anin vivocalibration curve was prepared between fluorescent intensity and pre-adjusted environmental pH values. Briefly,CFDA-SE-loaded wild-typeC. glabratacellswere incubatedwith 0.5 mM carbonyl cyanide m-chlorophenylhydrazone (CCCP; Sigma# C2759) at 30 ̊C for 10 min in 50 mM CP buffer adjusted to different pH values ranging from 4.0 to 7.5, with an interval of 0.5 unit.CCCP is an ionophore which dissipates the plasma membrane pH gradient, thus, rendering the intracellular pH similar to the extracellular pH. Fluorescent intensities were determinedand a calibration curvewas plotted between the ratio of intensity at 490 to430 nm versuspH.A polynomial distribution of fluorescent intensity signal and pH was observed for CFDA-SE probe(Figure2.1)and the graphequation was used todeterminethe intracellular pHof C. glabratacells

After 2-3 h exposure,phosphorimagerscreenwas scannedon Fuji FLA-9000 to acquire hybridization images. Next,signal intensity for each spot on the membrane for both input and outputsampleswas quantifiedusing Fuji Multi Gauge V3.0 software andpercentage intensity foreach spot relative tothe whole signal intensity ofthe membranewas determined.To identify mutants with altered survival profiles,ratio of output (Op) to input (Ip) signal for each spot (oligonucleotide tag)present on the membranewas calculated.Mutantsdisplaying at least 6-fold higher and 10-fold lower survival were selectedas “up’ (Op/Ip= 6.0) and ‘down’ (Op/Ip = 0.1) mutants, respectively

Of theligation mixture,2μl (of total volume of 10 μl reaction)was added to atube of 100μlultra competent DH5α bacterial cells and incubated in ice for 30 minutes. The tubewas quickly transferred to a water bath maintained at 42°C to give a heat shock for 90 seconds and again quickly transferred to ice. 1ml of LB broth was added to the tube and then incubated at 37°C for 1 hour. The bacterial cells were then pelletdownby centrifugation at 6000 rpm for 5 minutes and plated on LB agarcontaining appropriate antibiotic

To study the virulence of Xanthomonas oryzaepv. oryzicolastrains on rice plant two different inoculation methods, syringe infiltration and wound inoculation methods, were implimented. For infiltration method, bacterial suspension comprising of 1 × 108 cells/ml were infiltrated with needleless syringe into leaves of 4 to 6 week-old rice cultivar of susceptible Taichung Native-1 (TN-1) (Hopkins et al., 1992; Wang et al., 2007). Wound inoculation method was carried out by dropping an aliquot of 20 μl bacterial suspension comprised of 1 ×108cells/ml onto fully expanded leaf of 6-8 week green-house grown Taichung Native-1 cultivar of rice, and pricking with sterile needle for facilitating the entry of Xocinside the leaves throgh wound. For inititation of disease symptom, the inoculated plants were incubated in greenhouse with minimum and maximum temperatures of approximately 25 to 30 °C, respectively, and a relative humidity of approximately 60%. Water soaking symptom and lesion development was measured 4 to 10 days after inoculation. Likewise, for infiltration by wound inoculation method, lesion length was measured 14 days after inoculation. In both the cases, no lesions were observed in control experiments in which the leaves were inoculated with sterile wate

were chosen for qPCR. For all qPCR reactions,0.4 μl of cDNA template was used in a 20 μl reaction volume. Reactionswere performed anddata wereanalysed in ABI7500 real-time qPCR machine. Amplified products were run on 2% agarose gel to confirm amplification ofthecorrect size product. CTvalues of respective products were normalized with corresponding CTvalue of the housekeeping gene CgACT1. Relative change in expression was determined by comparative CTmethod,also referred as 2-∆∆CTmethod, utilizing following equation.Fold change upon treatment=2-∆∆CT∆∆CT=∆CT Treated-∆CT Untreated∆CTTreated= CTvalue for gene of interest upon treatment-CTvalue of internal control (CgACT1)upon treatment∆CTUntreated= CTvalue for gene of interest without treatment-CTvalue of internal control (CgACT1)without treatmentThe reaction cycling conditions were as follows1)95°C for 10 min (initial activation)2)95°C for 15 sec (denaturation)3)55°C for 30 sec (annealing)4)72°C for40 sec (extension)5)Go to step 2 (40 cycles)6)72°C for 10 min (final extension)

MESA GREEN qPCR mastermix (RT-SY2X-03+WOULR) supplied by Eurogentech was used in all qPCR experiments. Primers for real-time qPCR experiments were designed by using the Primer3 plus software to obtain 120-200 bp amplification products. Standardization of optimaltemplate and primer concentrationconditionswas done in a PCR reaction and concentrations resulting in good amplification withoutprimer dimers

were chosen for qPCR. For all qPCR reactions,0.4 μl of cDNA template was used in a 20 μl reaction volume. Reactionswere performed anddata wereanalysed in ABI7500 real-time qPCR machine. Amplified products were run on 2% agarose gel to confirm amplification ofthecorrect size product. CTvalues of respective products were normalized with corresponding CTvalue of the housekeeping gene CgACT1. Relative change in expression was determined by comparative CTmethod,also referred as 2-∆∆CTmethod, utilizing following equation.Fold change upon treatment=2-∆∆CT∆∆CT=∆CT Treated-∆CT Untreated∆CTTreated= CTvalue for gene of interest upon treatment-CTvalue of internal control (CgACT1)upon treatment∆CTUntreated= CTvalue for gene of interest without treatment-CTvalue of internal control (CgACT1)without treatmentThe reaction cycling conditions were as follows1)95°C for 10 min (initial activation)2)95°C for 15 sec (denaturation)3)55°C for 30 sec (annealing)4)72°C for40 sec (extension)5)Go to step 2 (40 cycles)6)72°C for 10 min (final extension)

MESA GREEN qPCR mastermix (RT-SY2X-03+WOULR) supplied by Eurogentech was used in all qPCR experiments. Primers for real-time qPCR experiments were designed by using the Primer3 plus software to obtain 120-200 bp amplification products. Standardization of optimaltemplate and primer concentrationconditionswas done in a PCR reaction and concentrations resulting in good amplification withoutprimer dimers