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Notes: Summary The physical and chemical properties and molecular structure of glycogen from Phymatotrichum omnivorum (Shear) Dugg. were studied. Glycogen samples from rabbit liver and shellfish were compared with Phymatotrichum glycogen in physicochemical properties. Analyses of purity showed the isolated glycogen was highly pure. Purified glycogen had an optical rotation of + 183.3°, and optical rotatory dispersion showed the absence of optically active substances between 200 and 600 nm. Maximum absorption of the glycogen-iodine complex was at 395 nm. I.R. spectra confirmed the α-1,4 linkage as well as α-d-glucopyranose units of the glycogen molecule. Alpha- and Beta-amylase studies indicated the average chain length was 13 glucose units with 43% limit dextrin. Results of periodate oxidation of glycogen agreed closely with the result of the amylase studies.

Notes: Summary Influences of various levels of dimethyl sulphoxide (DMSO) ranging from 0.04–1.28 M on growth, sporulation and spore germination ofRhizopus arrhizus in liquid and semi-solid media were investigated. Light enhanced the inhibitory effect of DMSO on growth and sporulation in both media. Inhibition of spore germination was observed with direct treatment with DMSO. The inhibition was higher in spores obtained from cultures grown on the DMSO semi-solid media.

Notes: Résumé La souche du virus en mosaique de la tomate et celle du virus en mosaique du tabac se sont trouvées alliées comme l'ont montré les résultats des expériences de précipitation et d'aglutination.

Notes: Zusammenfassung Die drei wachstumregulierenden Substanzen Indolessigsäure (IAA), Gibberellinsäure (GA) und Kinetin (K), wurden im Wachstumsversuch mitPhymatotrichum omnivorum (Shear) Dugg. miteinander verglichen. Die Resultate zeigen, dass Kinetin das Wachstum dieses Pilzes stärker anregt als Indolessigrenäs oder Gibberellinsäure.

Notes: Summary Growth of wheat in a nitrogen-free hydroponic co-culture with a mutant strain of the cyanobacterium Anabaena variabilitis (strain SA-1) was enhanced over plants grown with the parent strain SA-0. This increase was achieved in the dry weight, grain yield, and total nitrogen content of the plants. Nitrogenase activity of the mutant strain SA-1 was increased in a co-culture of the cyanobacterial mutant with wheat plants compared to the activity of the wild-type strain in association with wheat.

Notes: Abstract Direct association between wheat roots and an ammonia-excreting mutant of the cyanobacterium Anabaena variabilis, strain SA-1, was required for maximal enhancement of growth of wheat plants in nitrogen (N)-free, hydroponic medium. Over 85% of the cyanobacterial mutant SA-1 inoculated to the roots were adsorbed under non-saturating conditions. The adsorption process of SA-1 to wheat roots was biphasic: an initial rapid adsorption was followed by a slow phase with about 10% of the initial adsorption rate. The maximal adsorption rate of filaments observed was 1.6 mg dry wt. SA-1 adsorbed·plant−1·h−1. Bypassing CO2 fixation and sugar formation, the 14C label from [14C]sucrose was directly applied to leaf blades to study sugar translocation. The 14C label from this treatment appeared in the wheat culture medium within an hour. Nitrate-grown plants excreted about 30% of the 14C label into the medium, compared to only 10% excreted by wheat/Anabaena co-cultures. SA-1 assimilated 27% of all 14C translocated from [U-14C]sucrose applied to wheat leaves, and 14C label from this treatment was recovered from strain SA-1 after 30 min. Roots and cyanobacteria accounted for 51% of all radioactive label recovered in the plants co-cultured with SA-1 vs 20% for nitrate-grown plants. We studied the activity of β-fructosidase (invertase) in wheat of variety Yecora rojo. Roots from nitrate-grown wheat plants produced high levels of invertase activity, which converted over 85% of 3 mm sucrose into glucose and fructose in 24 h. The rate of sucrose disappearance in the medium of co-cultures using A. variabilis SA-1, was 70% of that of nitrate-grown plants, but the levels of glucose and fructose in these cultures were always very low during sucrose conversion, suggesting hexose assimilation. To study the role of diffusible metabolites, a dialysis membrane was employed to separate the ammonia-excreting SA-1 from the wheat roots. Containing SA-1 in a dialysis bag away from direct root contact, severely limited leaf growth to less than one-third of the growth rate of nitrate control cultures. Ammonia produced by mutant SA-1 in dialysis bag cultures was excreted into the medium at 0.4 mm vs 1.2 mm in free-living cultures, but ammonia was not detectable in co-cultures with or without the dialysis bag containing the mutant. The nitrogenase activity derepressed in the mutant and responsible for ammonia excretion was always higher in the association co-cultures than in either free cells or in dialysis-bag cultures. The nitrogenase activity of strain SA-1 was highest (200 μmol ethylene formed·mg−1 Chl·h−1) when the cyanobacterium was associated with the root tips. Dialysis membrane separation of plant and cyanobacterium severely inhibited growth of wheat during a complete growth cycle of 2 months. Total biomass and grain yield were very similar for control cultures without inorganic N or SA-1, and for diffusion cultures containing SA-1, kept in a dialysis bag around the roots. Total biomass of the association co-culture attained 75% of the biomass of the nitrate-grown control. It is proposed that wheat roots supplied fructose derived from sucrose for growth and nitrogen fixation of SA-1 in the light, and that ammonia excreted by SA-1 was utilized by the wheat plant for its own growth.

Notes: Abstract A simple and specific medium consisting of chitosan, trypticase, Tween-80 and agar is devised to isolate the organisms directly from the clinical specimens and to produce germ tubes and chlamydospores for rapid differentiation and identification of Candida albicans from other closely related Candida species. By manipulating the incubating conditions, the specific phase of the organism can be produced in liquid or on solid medium at different time intervals to study the physiology of the organism. Many methods and media have been proposed in the past for identification of Candida albicans and to differentiate this from the closely related species of Candida (5–8, 15). Taschdjian, Burchall&Kozinn (15) showed that C. albicans produces germ tube within an hour or two when it is grown in human or animal serum or serum substitutes. The specificity of this germ tube test was later confirmed by various workers by using different media (3–5). The distinctive feature that differentiates C. albicans from other species is the production of chlamydospores (14). However, in all these studies three types of media were required to isolate the organisms from clinical specimens and to produce germ tubes and chlamydospores for identification. Recently studies have shown that a single medium can be employed to produce both structural components of the organism from the primary isolation medium but the preparation of the medium is more exhaustive (1) and time consuming (13) than the medium to be described here. The present investigation was therefore undertaken to develop a simple and specific medium to isolate the organism directly from the clinical specimens and to produce various morphological phases of Candida albicans to differentiate from other closely related Candida species for clinical diagnosis and to provide a medium to study the physiology and metabolism of the organism under in vitro conditions.