The occurrence in soil of a large group of bacteria which require vitamin B12 has been reported by Lochhead and Thexton (1952). Thirty cultures obtained from 534 isolates showed dependence upon vitamin B12 for growth. Lochhead and Burton (1954) grouped these 30 cultures into 10 types, based on morphological and physiological characteristics. A study of the nature of the vitamin B12 requirements...

Cell-free extracts of Streptomyces bikiniensis contain an adenosine 5'-triphosphate-dependent kinase which inactivates streptomycin (Sm) and dihydrostreptomycin by phosphorylation. The products have been identified as streptomycin 6-phosphate and dihydrostreptomycin 6-phosphate. Activity was not present in logarithmic-phase cells, which were susceptible to 25 mug of Sm per ml. In stationary-pha...

The dominant aerobic microorganism in cattle feedlot waste (FLW) is a corynebacterium. It is ubiquitous to FLW except on sites where antibiotics are a constant part of the animals' diet. The organism requires DL-aspartic acid as its nitrogen source for growth, and individual strains also require or are stimulated by L-tyrosine; acetate serves as the carbon source. Amylolytic activity is weak; p...

Microorganisms, such as bacteria, microphytes (tiny plants such as microscopic algae), and protists (a diverse group of single cell organisms), are present in every part of the biosphere: giant plankton blooms in the oceans, protozoa in our lakes and ponds, beneficial or pathogenic bacteria in our bodies are but a few examples that we are all familiar with. The ability of microorganisms to move...

Few quantitative measures of genome architecture or organization exist to support assumptions of differences between microorganisms that are broadly defined as being free-living or pathogenic. General principles about complete proteomes exist for codon usage, amino acid biases and essential or core genes. Genome-wide shifts in amino acid usage between free-living and pathogenic microorganisms r...

Lipid droplet (LD) is a cellular organelle that stores neutral lipids as a source of energy and carbon. However, recent research has emerged that the organelle is involved in lipid synthesis, transportation, and metabolism, as well as mediating cellular protein storage and degradation. With the exception of multi-cellular organisms, some unicellular microorganisms have been observed to contain ...

From a biological perspective, a dynamic model describing the cultivation and flocculation of a microorganism that uses two different kinds of nutrients (carbon source and nitrogen source) is proposed. For the proposed model, there always exists a boundary equilibrium, i.e., Rhodopseudomonas palustris -free equilibrium. Furthermore, under additional conditions, the model also has five positive ...

The influence of rhizosphere/rhizoplane culture conditions on the ability of various rhizobia to bind soybean seed lectin (SBL) was examined. Eleven strains of the soybean symbiont, Rhizobium japonicun4 and six strains of various heterologous Rhizobium species were cultured in root exudate of soybean ( Glycine max IL.I Merr.) and in association with roots of soybean seedlings which were growing...

Triclosan, a synthetic antimicrobial agent, has been considered as an emerging environmental contaminant. Here we reported a triclosan-degrading wastewater bacterial isolate, Sphingopyxis strain KCY1, capable of dechlorinating triclosan with a stoichiometric release of chloride. The stain can degrade diphenyl ether but not 2,4,4'-tribromodiphenyl ether and 2,2',4,4'-tetrabromodiphenyl ether, de...