Protein synthesis elongation factor EFTu from streptomyces collinus producing kirromycin

Elongation factor EFTu of Streptomyces collinus has been purified. The molecular weight of the factor determined by SDS-polyacrylamide gel electrophoresis is 52,500 (±1,500). The factor shares common immunochemical determinants with EFTu of Streptomyces aureofaciens and Escherichia coli. The factor is not involved in the mechanism of resistance to the drug produced, since translation of poly(U) in the presence of EFTu and ribosomes of S. collinus is sensitive to the kirromycin effect.     

Construction of multiple herbicide resistant ammonia excreting strains of cyanobacteriumNostoc muscorum

Summary Machete resistant (Mat ^r), basalin resistant (Bas ^r), 3(3,4 dichlorophenyl)-1,1-dimethyl urea resistant (DCMU ^r), atrazine resistant (Atr ^r) and propanil resistant (Prp ^r) phenotypes ofGloeocapsa sp. were cotransformed toNostoc muscorum at high frequency. Spontaneously occurring mutants of the multiple herbicide resistant transformant containing L-methionine-DL-sulfoximine resistant (Msx ^r), ethylene diamine resistant (Eda ^r), or phosphinothricin resistant (Ppt ^r) glutamine synthetase (GS) showed extracellular liberation of ammonia resulting from fixation of N₂ under photosynthetic conditions. Results suggest a definite role of GS activity in regulation of extracellular ammonia.     

Optimization and characterization of an extracellular polysaccharide produced byPaecilomyces lilacinus

Summary A new strain of the fungusPaecilomyces lilacinus has been isolated which produces a viscous extracellular polysaccharide in a simple medium. The polysaccharide consists of glucose and galactose moieties. The viscosity of the polysaccharide was unchanged by a range of temperature and pH.     

Optimization and characterization of an extracellular polysaccharide produced byMoniliella pollinis

Summary A yeast strainMoniliella pollinis produces an extracellular highly viscous gum-like polysaccharide of glucan type in a simple mineral medium. Optimum conditions for its production and properties are described. The viscosity decreased after lyophilization.     

Extracellular L-glutaminase production by marine bacteria

Summary Four species of bacteria which includedPseudomonas fluorescens,Vibrio cholerae andVibrio costicola were observed to produce glutaminase both as extracellular and intracellular fractions. Comparatively both the fractions were higher in mineral media supplemented with 1% glutamine than in nutrient broth added with or without glutamine. Extracellular glutaminase production was about 2.6–6.8 times greater than the intracellular production by all the tested strains.     

Conditions for production of extracellular protein byBacillus brevis 47

Bacillus brevis 47 was grown in shake flasks under varying conditions of agitation, culture volume, inoculum size, medium supplementation, and initial pH. It was found to have a high demand for oxygen, and, under appropriate conditions, could produce up to 9 g/l of two extracellular wall proteins in 24 h.     

Optimization and characterization of an extracellular polysaccharide produced byGlomerella cingulata

Summary A new strain of the fungusGlomerella cingulata has been isolated, which produces an extracellular highly viscous polysaccharide in a simple mineral medium. Optimum conditions for its production and properties are described. The polysaccharide produced was a glucan type. The viscosity remained stable during storage over a period of seven days. Large changes in temperature and pH have no effect on viscosity.     

Bioemulsifier production by an oleaginous yeastRhodotorula glutinis IIP-30

Summary A locally isolated oleaginous strain ofRhodotorula glutinis strain IIP-30 produced a growth associated extracellular emulsifying agent while utilizing glucose during fed batch fermentation under nitrogen limitation at 30°C and pH 4. 0. Similar optimum conditions were also noted for intracellular lipid accumulation.     

Cadmium adsorption by bacterial capsular polysaccharide coatings

Conclusions Excretion of a polysaccharide capsular coating byP.putida provided enhanced cadmium uptake when compared to the noncapsularP.cruciviae. As this advantage is most significant for cadmium concentrations below 2.5 mg/l, levels which are commonly found in waste discharges, it does suggest a potential role for extracellular polysaccharide producers as biosorbents. These encouraging results have led to further work to determine the desorption characteristics, by pH adjustment, ofP.putida along with long term viability after successive cycles of adsorption and desorption.     

The structure of nicotine blue from Arthrobacter oxidans

Summary Nicotine blue was separated into two major components. Their chromophores are anions of the diazadiphenoquinones (1) (nicotine blue I) and (2) (nicotine blue II). The dihydrate of the potassium salt of (1) is the major component of the extracellular crystals which are excreted on a solid medium. The acid-labile nicotine blue II is water-soluble and the main coloring agent of the agar and culture broth respectively.     

A method for estimating biomass ofAgaricus bisporus in a solid substrate,composted wheat straw

Summary Growth ofAgaricus bisporus mycelium in liquid cultures, or linear growth in compost, was directly proportional to the quantity of extracellular laccase. Laccase activity measured during the mycelial colonisation of composted straw can therefore be used to quantify the mycelial growth. Immunological methods indicate that the laccase appears to be a specific product ofA. bisporus or very closely related species.     

Production of extracellular 5-aminolevulinic acid byClostridium thermoaceticum grown in minimal medium

Summary A growth associated formation of extracellular 5-aminolevulinic acid (ALA) was found in the homoacetogenesis of glucose byClostridium thermoaceticum grown in minimal defined medium. The growth and ALA production was enhanced by L-cysteine HCl both in complex medium (UM) and minimal defined medium (MDM). The amount of ALA produced extracellularly in MDM wasca. 15 mg/L after 90-h anaerobic cultivation (cell-mass: 1.5 g/l; glucose consumed: 20 g/l).     

A self-referential model for the formation of the genetic code

A model for the formation of the genetic code is presented where protein synthesis is directed initially by tRNA dimers. Proteins that are resistant to degradation and efficient RNA-binders protect the RNAs. Replication becomes elongational producing poly-tRNAs from which the mRNAs and ribosomes are derived. Attributions are successively fixed to tRNAs paired through the perfect palindromic anticodons, with the same bases at the extremities (5′ANA: UNU 3′; GNG: CNC; principal dinucleotides, pDiN). The 5′ degeneracy is then developed. The first pairs to be encoded correspond to the hydropathy correlation outliers (Gly-CC: Pro-GG and Ser-GA: Ser-CU) and to the sector of homogeneous pDiN, composed by two pyrimidines or two purines. These amino acids are preferred in the N-ends of proteins, stabilizers of proteins against catabolism and strong RNA-binders. The next pairs complete the sector of homogeneous pDiN (Asp, Glu-UC: Leu-AG and Asn, Lys-UU: Phe-AA). This set of nine amino acids forms the protein cores with the predominant aperiodic conformation. Next enter the pairs with mixed pDiN (one purine and one pyrimidine), the RY attributions composing the protein N-ends and the YR attributions the C-ends. The last pair contains the main punctuation signs (Ile, Met, iMet-AU: Tyr, Stop-UA). The model indicates that genetic information emerged during the process of formation of the coding/decoding system and that genes were defined by the proteins. Stable proteins constructed the nucleoprotein system by binding to the RNAs that produced them. In this circular rationale, genes are memories in a metabolic system for production of proteins that stabilize it. The simplicity and the highly deterministic character of the process suggest that the Last Universal Common Ancestor populations could be composed, in early stages, of lineages bearing similar genetic codes.     

Characterization of extracellular substrate specific glucose and xylose isomerases of Chainia

Summary Specific glucose and xylose isomerases have been identified in cell-free culture filtrates of a Chainia species. Treatment with DEAE-cellulose selectively adsorbed xylose isomerase activity while only the glucose isomerase was adsorbed on CM-cellulose. Glucose isomerase was completely inhibited by xylose at 1.3 × 10^-4 M concentration. The differential identity of the extracellular glucose and xylose isomerases, unique to Chainia, is discussed.(NCL Communication 3562)     

Effect of media composition on the production of extracellular amylase from the thermophilic fungusThermomyces lanuginosus

Summary The production of extracellular amylase by the thermophilic fungusThermomyces lanuginosus was studied in shake flask cultures with different carbon sources in the growth medium. Maximum amylase production was obtained with dextran as carbon source. The greatest yield of amylolytic activity was found when low molecular weight dextrans were used as carbon source.     

A constitutive endoglucanase (CMCase) from Bacillus licheniformis-1

Summary Bacillus licheniformis-1 elaborated a constitutive extracellular CMCase. The temperature and pH optima of the enzyme were 55°C and 6.1 respectively. Its production was enhanced in the presence of easily metabolisable sugars and was lower when cellulosic sources were used.Abbreviations used CMC Carboxy Methyl Cellulose. - CP-60 Cellulose Powder 60 - CP-100 Cellulose Powder 100 - CP-X Cellulose Powder X     

Isolation and characterization of AStreptomyces C5 mutant strain hyperproductive of extracellular protease

Summary A pleiotropic streptomycete mutant was isolated that overproduced extracellular protease activity on azocasein, whereas the parent strain,Streptomyces C5, produced only negligible extracellular azocaseinase activity. Also unlike the parent strain, the mutant, designated C5-A13, was nonpigmented, and was unable to sporulate or produce antibiotics.     

Screening of yeast strains capable of hyperproducing amylolytic enzymes

Summary Fifteen strains of yeast, which produced an extracellular amylolytic enzymes, were isolated from nature. One of them produced more than 100 times the enzyme activity in comparison with the 14 strains and the extremely hyperproducing strain of yeast was identified asCandida sp. 347. Paper chromatograms of the amylolytic enzyme demonstrated activity of amyloglucosidase. The optimum pH for activity of the enzyme was 5.5–6.0 and optimum temperature was 60°C.     

Callus culture as substrate for the production of specific cell wall degrading enzymes for derived protoplast isolation

Callus culture of spruce (Picea excelsa LINK) appears to be a suitable substrate for the fungusTrichoderma reesei to produce an efficient extracellular lytic system for protoplast isolation. In comparison with Onozuka R-10 cellulase, a yield of protoplasts from the spruce callus 2·5 higher was obtained. Another testea commercial cellulase DK was less efficient. The addition of Macerozyme R–10 significantly enhanced release of protoplasts within all tested enzyme preparations. No difference in the viability of protoplasts has been observed.     

Lipase production byCandida rugosa: Fermentation behaviour

Summary Extracellular lipase production byCandida rugosa growth has been studied. The main growth parameters, and the lipase activity in the culture broth were determined in order to identify the maximum of enzyme activity.The effect of lipidic material and size and growth phase of the inoculum on enzymatic production have been studied. Maximum extracellular lipase activity was associated with an increase in enzyme production when the number of viable cells started to decrease.