Conditions for Competence in the Bacillus licheniformis Transformation System

Some variables in the Bacillus licheniformis transformation system, such as inoculum size, initial cell density in transformation medium, and time of optimal competence, have been explored, and a methodology has been developed to obtain greater reproducibility and maximal competence for transformation. The transformation system in B. licheniformis has been shown to be similar to that of B. subtilis in a number of respects, including "dormancy" of transformed cells and the concentration of transforming deoxyribonucleic acid required for saturation.     

Persistence of Salmonella typhimurium on Fabrics

The objective of this study was to determine the feasibility of using airborne T3 coliphage as a viral tracer in microbial aerosols. Although T3 coliphage was relatively stable when stored either at temperatures ranging from 21 to 37 C or in the frozen state at -20 C, there was a 2-log loss in infectivity when stored for 72 days at 4 C. Either agitation of stored coliphage suspensions held at 31 C or wide fluctuations in storage temperature produced an increased loss of infectivity. In the airborne state, freshly prepared coliphage and stored coliphage behaved similarly, with survival diminishing as the relative humidity (RH) was lowered. The greatest loss occurred during the first five min following aerosolization. The results showed that only under certain conditions of temperature and relative humidity can T3 coliphage be used as a satisfactory aerosol tracer.     

Specific Learning Disorders—Natural History and Current Views

Each professional, whether pediatrician, neurologist, psychiatrist, psychologist or teacher, in evaluating behavioral, neuromuscular, and emotional factors with the tools of his discipline, can arrive independently at very similar views regarding etiology and diagnosis of learning and language disorders. Even though this is possible, it is essential to have the many disciplines work together. This manner of sharing information is not only supportive to the patient, but to the physician as well.The pediatrician''s role does not stop, however, with the diagnosis, but continues with the working through of problems that the child and parents present to one another.     

Amino acid sequences around the cystine residues in horse growth hormone

The cystine-containing peptides of horse growth hormone were isolated and their amino acid sequences determined. Four unique half-cystine residues occur in two peptides, one containing 11 and the other, at the C-terminus of the protein, 15 amino acids. These sequences are compared with published data on growth hormones from other species.     

About phoma liliana Chandra & Tandon

Summary In vitro,Phoma liliana could not be distinguished from the later-describedP. ehretiae and two incidental isolates fromMangifera andChrysanthemum. Starting from the principle of the classification in the Deuteromycetes, our conclusion is that we must speak of one and the same form-species, which can be found on different plants.     

Ultrastructural evidence for the biflagellate origin of the uniflagellate fungal zoospore

Summary The morphological similarities between the kinetosome and the second centriole of the zoospores of Phlyctochytrium kniepii and P. punctatum (Chytridiomycetes) suggest that the second centriole in the chytrid zoospore is a vestigial flagellum base. It is suggested that the term vestigial kinetosome may also be used when referring to the structure which is presently termed the second centriole of the chytrid zoospore. Morphological similarities between the chytrid zoospores of P. kniepii and P. punctatum and the zoospores of Rhizidiomyces apophysatus (Hyphochytridiomycetes) are noted. The possible biflagellate origin of fungi with uniflagellate zoospores is discussed. The third fiber (C fiber) of the kinetosome triplet is shown to form as an outgrowth of the B fiber of the kinetosome doublet.     

THE FINE STRUCTURE OF BLASTOCLADIELLA EMERSONII ZOOSPORES

The zoospore of Blastocladiella emersonii has been re-examined with the electron microscope. The following new findings were made. A double unit-membrane system surrounds all cell organelles except γ-bodies, vacuoles and a few fragments of membranes. Lipid granules on one side of the large mitochondrion alternate with vesicles. The kinetosome of the posterior flagellum does not have any central fibrils as previously reported; a small, cylindrical structure is found within its anterior end. An associated centriole is located next to the kinetosome. Three striated rootlets pass from the kinetosome by separate channels through the mitochondrion. There appears to be no connection between the striated rootlets and the mitochondrion. Microtubules originating at the anterior end of the kinetosome pass into the cytoplasm between the mitochondrion and the nuclear cap. Long, dense strands were observed in some nuclei. The axoneme is taken up into the spore during encystment and is found in the freshly encysted spore. No trace of the flagellar sheath has been found in the encysted spore.