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Rivka Rudner, Professor Emerita of Biology

Email: This e-mail address is being protected from spambots. You need JavaScript enabled to view it
Office: Room 820HN
Phone: (212) 772-5233

Lab Web Site: http://rudner.bioweb.hunter.cuny.edu

Education:

  • B.A., 1957, New York University
  • Ph.D., 1961, Columbia University
  • Postdoc., 1961-1964, College of Physicians and Surgeons, Columbia University

Research Interest:

  • Differential Expression of Ribosomal and Transfer RNA Genes in Bacillus subtilis and
    Our research deals with the heterogeneity in organization of the conserved and redundant rRNA (rrn) operons and tRNA (trn) genes, their expression and the molecular mechanism involved in the regulation of ribosome synthesis in Bacillus subtilis. Specifically, we deal with the evolutionary importance for the endospore-forming bacteria for possessing a high clustering of rrn operons near the origin of replication and large tRNA gene clusters (2-21) downstream of all 10 ribosomal RNA gene sets. Studies on the differential expression of seven out of the 10 rrn operons with single-copy lacZ fusions capable of integrating at the native rrn site or at heterologus loci (amyE, thrC) have shown that all are under growth-rate control and are grouped into strong (rrnO, rrnW), intermediate (rrnA, rrnJ, rrnE), and weak (rrnD, rrnB) the latter are associated with large cluster of 16 and 21 tRNA gene clusters respectively. We are investigating the role and interaction of the tandemly arranged promoters (P1, P2), the Upstream Activating Sequences (UP and UAS) and the 7 bp discriminator sequence in growth-rate regulation and in the stringent control using cloned individual promoter elements without the UAS and after mutating critical regulatory regions of selected rrn operons. We follow stable RNA synthesis, ß-galactosidase measurements and (p)ppGpp accumulations in cells with genetic backgrounds that are relA+, relA-, relA(S) and rpoB grown as a function of different growth rates, during amino acid starvation or carbon source limitation.

    Our second project deals with how bacterial populations specifically various Bacilli can behave in an organized manner to generate highly geometrically morphologies or morphotypes on solid and semi-solid surfaces. Five morphotypes have been generated for B. subtilis under nutrient scarcity and hardness of the agar surface: 1) the common compact round colonial growth with rough edges, (B); 2) tree branches with tip splitting growth, (T); 3) curled or chiral growth with the same handedness branches, (C); 4) vortex branched growth led by bacteria droplets that spin around a common center, (V); that 5) at times become spiral vortex (SV). These forms are stably inherited exhibiting many physiological and genetic properties distinct from B. subtilis. Sequencing of the 16S rDNA gene and Southern hybridization suggests that the colonial patterns may be the result of another Bacilli coexisting with B. subtilis which is activated during certain hostile conditions. Work is on going to understand the genetic basis of morphotypes and the role played by chemotaxis in generating and maintaining these striking differentiated structures.

Selected Publications:

  • Kearns, D.B., Chu, F., Rudner, R., and Losick R. Genes governing swarming in Bacillus subtili and evidence for a new phase variation mechanism controlling surface motility. Molecular Microbiology 52:357-369 (2004).
  • Shaver, Y. J., Nagpal, M.L., Fox, K. F., Rudner, R., and Fox, A. Variation in the 16S- 23S rRNA intergenic spacer regions among Bacillus subtilis 168 isolates. Molecular Microbiology 42:101-110 (2001).
  • Feinberg L., Jogensen, J., Haselton, A., Pitt, A., Rudner, R, and Margulis, L. Arthromitus (Bacillus cereus symbionts) in cockroach Blaberus giganteus: Dietary influences on bacterial develop and population density. Symbiosis 27: 109- 123 (1999)
  • Rudner, R. Murray, A., and Huda, N. Is there a link between mutation rates and the stringent response in Bacillus subtilis. In Molecular Strategies in Biological Evolution. L.H. Caporale (ed) Ann. of the New York Academy of Sciences, pp 418-422 (1999)
  • Rudner, R., Martsinkevich, O., Leung, W., and Jarvis E. D. Classification and genetic characterization of pattern-forming Bacilli. Molecular Microbiology 27: 687-703 (1998).
  • Rudner, R. , Martsinkevich, O., Leung, W., and Jarvis, E.D. 1998. Classification and genetic characterization of pattern-forming Bacilli. Submitted to Mol. Microbiol. 27:687-703.
  • Rudner , R. , Studamire, B., and Jarvis,E. D. Determination of restriction fragment length polymorphism in bacteria with ribosomal RNA genes. In Methods of Enzymology: Bacterial Pathogenesis vol.235 Part A Identification and regulation of virulence factors. Clark V. L. and Bavoil P.M. (eds.) pp184. Academic Press, In .San Diego,California (1994) 2nd Ed (1997)
  • Gropp, M., Eizenman, E., Glaser, G., Rudner, R. 1994 A relA(s) suppressor mutant allele of Bacillus subtilis which maps to relA and responds only to carbon limitation. Gene, 140: 91-96.
  • Rudner, R., Studamire, B., Jarvis, E.D. 1994 Determination of restriction fragment length polymorphism in bacteria with ribosomal RNA genes. Bacterial Pathogenesis, Vol 235. Methods in Enzymology: p.184. Clark, V.L., Pavoli, P.M.(ed) Academic Press Inc., San Diego, CA.
  • Rudner, R., Chevrestt, A., Buchholz, S.R., Studamire, B., White, A.-M, Jarvis, E.D. 1993 Two tRNA gene associated with rRNA operons rrnD and rrnE in Bacillus subtilis. J. Bacteriol. 175: 503-509.
  • Rudner, R., Martsinkevich, O., Leung, W., and Jarvis E. D. Classification and genetic characterization of pattern-forming Bacilli. Molecular Microbiology 27: 687-703 (1998).

Last Updated ( Tuesday, 25 May 2010 14:26 )