FUNCTlONAL ANALYSIS OF THE PHOB/COTA REGlON OF THE BACILLUS SUBTILIS CHFDMOSOME

The phoB-rrnE-groESL-gutR-cotA region (70kb) of the Bacillus subtilis genome contains several operons of unknown or not well known function. We disrupted 57 or fs of unknown functlon and determhed their transcriptional activity wuh lacZ and Northern analysts. Some features of the operons found are as follows. A large operon involved in degradation and ncorpolation of konjac glucomannan consists of eight orfs whose predicted products include PTS system proteins as well as mannan digestng extracellular enzyme. The expression of thls operon was induced by konlac glucomannan. especially by dissaccharides and repressed by glucose or mannose. Inherent restrictlon/modificatlon system genes hsdMR/hsdMM consist of tandemly locating modification genes ydiO and ydiP. and separately located restriction gene ydiS which make an operon with two other genes. ydiR and ydjA. ydiO and ydiP make an operon and they were co-transcribed with upstream groESL gene at TO and T1 stage. Five orfs, ydiA to ydiE, make an operon down stream of rrnE operon. YdiA and YdiD were not essential for growth but YdiB. YdiC, and YdiE are essential. The last gene codes for an protein similar to P.haemolytica osialoglycoprotein endopeptidase. This oporon is transcribed during growth. The expression of ydjF.ydiG,ydiH. and ydjl showed a peak at T1 stage. LacZ activity and the signal of Northern analysis coincided. They constitute an operon down stream of glucitol utilization operon. Some genes such as ydgK, ydhJ, and ydhL are transcribed during growth and other genes and operons such as ydhD, ydhF. ydhU and ydjP/Q are transcribed aner T4 stage.