The B. subtilis DhelD allele rendered cells proficient in transformational recombination and moderately sensitive to methyl methanesulfonate when present in an otherwise Rec strain. The DhelD allele was introduced into rec-deficient strains representative of the a (recF strain), b (addA addB), g (recH), « (DrecU), and z (DrecS) epistatic groups. The DhelD mutation increased the sensitivity to D...

The chemical composition of the essential oil obtained from the aerial flowering parts of Ziziphora clinopodioides subsp. bungeana (Juz.) Rech. f. was analyzed by GC and GC-MS. Thirty-two components representing 97.1% of the total oil were identified. Oxygenated monoterpenes (94.3%) were the predominant fraction of the oil with pulegone (65.2%), isomenthone (11.9%), 1,8-cineole (7.8%) and piper...

The cytotoxic chloroform fraction of Euphorbia aellenii afforded two cycloartane type triterpenes — cycloart-25-en-3,24-diol (1) and 24-methylene-cycloartan-3-ol (2) — for the first time from this plant. Preparation of cycloartane derivatives, 3, 24-O-diacetyl-cycloart-25-en as compound 3 and 3-O-acetyl-24-methylene-cycloartan (4) were conducted by acetylating of 1 and 2, respectively. The ...

The hydrodistilled essential oil from flowers of Hymenocrater platystegius Rech. f., which isendemic to Iran, was analyzed by GC and GC/MS. Twelve compounds representing 80.4%of the flowers oil of H. platystegius were identified. This oil was particularly rich in α-pinene(25.8%) and limonene (20.9%); another major component of the oil was β-pinene (12.2%).

Bacillus subtilis recombination-deficient mutants were constructed by inserting a selectable marker (cat gene) into the yppB and ypbC coding regions. The yppB:cat and ypbC:cat null alleles rendered cells sensitive to DNA-damaging agents, impaired plasmid transformation (25- and 100-fold), and moderately affected chromosomal transformation when present in an otherwise Rec+ B. subtilis strain. Th...

In this survey, the chromosome counts of eight Nepeta L. species were investigated and karyotypic diversity among these was studied. The examined belong to N. cephalotes Boiss. group, namely eremokosmos Rech.f., gloeocephala Rech. f., Boiss., pungens (Bunge) Benth., ispahanica mahanensis Jamzad & Simonds, hormozganica denudata Benth. collected from different habitats in Iran. ploidy levels,...