The fatty acid profile and lipid content of four strains of Salmonellatyphimurium were evaluated. The fatty acid profiles are characterized by the production of hexadecanoic acid (16:0), cyclic fatty acids (C17, C19) and hydroxytetradecanoic acids. Quantitative differences in the amounts of phospholipid were observed among the strains. The total extractable lipid and fatty acid contents were similar, but the presence of 3-hydroxytetradecanoic acid and small amounts of 2-hydroxytetradecanoic acid in all strains suggest the presence of lipid A. The quantities of phosphatidylserine (PS), the presence of 2- and 3-hydroxytetradecanoic and small amounts of a third isomeric 14:0 hydroxy fatty acid methyl ester may provide some insight into the relative difference in the strains. However, the amounts of quantified PS were the only observed differences among the strains.
Myrothecium verrucaria produced high levels of chitinases in a medium containing chitin used as a sole carbon source. Adding 0.03% urea increased the enzyme yield 4-fold in 7 days compared to the control. Adding oxgall (0.1%) to the growth medium gave the maximum activity (acid-swollen chitin-degrading activity, 2.0IU/ml) in 7 days. The biochemical characterization of the chitinase revealed its broader temperature (25-55°C) and pH (4.0-6.5) profiles of activity which showed its potential application in fungal mycelia degradation. Compared to commercial lytic enzyme preparations (NovoZym 234 and Onozuka R-10), M, verrucaria culture filtrate had 5-6 times more chitinase activity. And this produced significantly higher levels of N-acetyl-D-glucosamine from the fungal mycelia preparations under study.
In an attempt to elucidate the phylogeny of the C1-compound-utilizing bacteria, dendrograms were drawn for gram negative obligate and facultative methanol-utilizing bacteria, a methane-utilizing bacterium, and other gram negative bacteria on the basis of their 5S ribosomal RNA sequences published to date. Phylogenetic distances were calculated using Knuc, a parameter for phylogenetic distance based on the number of nucleotide substitutions reported by Kimura, and Dnuc, a modified form of Knuc proposed by Hori and Osawa. The dendrograms were drawn using the unweighted pair-group (UPG) average clustering method. Obligate methanol-utilizing bacteria belong to one cluster of gram negative bacteria, while facultative methanol-utilizers are members of another. There is no close phylogenetic relationship between obligate and facultative methanol-utilizing bacteria.
The qualitative and quantitative distribution and seasonal variation of luminous bacteria in the sediments of Vellar estuary, Porto Novo, South India (11° 29′N, 79°46′E) was studied. The luminous bacterial population ranged from 5.1×103 to 3.2×104CFU/g dry weight in station I and 2.4×103 to 9.1×103CFU/g dry weight in station II. The salinity of the estuarine water appeared to have an indirect relationship with luminous bacterial counts in the sediment. The maximum number of luminous bacteria were recorded during summer followed by a decline before the monsoon. The counts were at a low level during monsoon and then started to increase after the monsoon season. Vibrio harveyi, V. fischeri and Photobacterium leiognathi were the species recorded in the sediments. V. harveyi was the dominant species being present throughout the year.
Metabolically active heterocysts isolated from Anabaena sp, strain CA showed high rates of light-dependent nitrogenase activity. When these active heterocysts were incubated under light of various wavelengths, they were most active under blue light, followed by yellow and red light respectively. Involvement of phycobiliproteins in transferring light energy to photosystem I in isolated heterocysts is discussed. Aldolase, phosphofructokinase and catalase activities were also studied in extracts of vegetative cells as were heterocysts from Anabaena sp. strain CA.
Eight strains of the Q9-equipped heterobasidiomycetous yeast species, Rhodosporidium malvinellurn, Rhodosporidium toruloides, and Leucosporidiumscottii and the Q9-equipped anamorphic yeast species, Rhodotorulalactosa were examined as to the partial sequence determinations of 18S rRNA and 26S rRNA. The positions determined were 1451 through 1618 of 18S rRNA and 492 through 625 of 26S rRNA. The two determinations of the partial sequences of 18S rRNA and 26S rRNA showed that the four species mentioned above constituted their own separate clusters. Rhodosporidium malvinellum occupied a unique situation. The phylogenetic relationship between R. malvinellum and R. toruloides was more distant than that between R. toruloides and L. scottii. The data indicated that these three heterobasidiomycetous yeast species are distinguished from each other at the generic level. The new genus Kondoa was proposed for R. malvinellum.