A variety of mutants having different colony characteristics, morphology and soluble pigmentation were generated from
Fusarium fujikuroi
by exposure to UV radiation. Mutants were selected that formed ...dry, compact, small colonies with reddish-violet pigment on regeneration agar plates. The production of bikaverin by Mut-4 was examined in shake flasks in media with different nitrogen and carbon sources. The optimal C: N ratio for the maximal bikaverin production by Mut-4 was 150:1. It produced still higher bikaverin (6.3 g l
−1
) in a medium containing defatted cottonseed meal as nitrogen source, in combination with glucose. Bikaverin produced was extracted, purified and characterized by UV-visible and NMR spectroscopy. Bikaverin production in the present investigation was substantially higher than that reported by earlier investigators in submerged and solid-state fermentations.
Microbial competition for territory and resources is inevitable in habitats with overlap between niches of different species or strains. In fungi, competition is brought about by antagonistic ...mycelial interactions which alter mycelial morphology, metabolic processes, secondary metabolite release, and extracellular enzyme patterns. Until now, we were not able study in vivo chemical interactions of different colonies growing on the same plate. In this report, we developed a fast and least invasive approach to identify, quantify, and visualize co culture-induced metabolites and their location of release within
Schizophyllum commune
. The pigments indigo, indirubin, and isatin were used as examples to show secondary metabolite production in the interaction zone with
Hypholoma fasciculare
. Using a combinatory approach of Raman spectroscopy imaging, liquid extraction surface analysis (LESA), and high-resolution mass spectrometry, we identified, quantified, and visualized the presence of indigo and indirubin in the interaction zone. This approach allows the investigation of metabolite patterns between wood degrading species in competition to gain insight in community interactions, but could also be applied to other microorganisms. This method advances analysis of living, still developing colonies and are in part not destructive as Raman spectroscopy imaging is implemented.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Archaeological excavations carried out in the ancient settlement of Sumhuram (3rd century BC–5th century AD) in the area of Khor Rori (Dhofar Governorate, southern Oman), brought to light pottery ...showing a pink-violet substance. In order to reveal the nature of this pink-violet colour, the substance was chemically examined by laser desorption-ionization mass spectrometry (LDI-MS) and high performance liquid chromatography-diode array detection (HPLC-DAD). The analytical investigations provided a detailed molecular composition of the organic fraction of the pink-violet material, highlighting the presence of 6,6′-dibromoindigo, 6-monobromoindigo, 6,6′-dibromoindirubin, 6- and 6′-monobromoindirubin, indigo and indirubin. The results revealed that shellfish purple was the source. In addition, in some of the pottery fragments, alizarin and purpurin, which are the molecular markers of madder type dyestuffs, were also ascertained by LDI-MS. The analytical results enabled us to draw hypotheses not only on the possible function of such vessels as dye baths, but also that, since Sumhuram was one of the most important harbours in southern Arabia during the pre-Islamic time, it was also possibly a centre for the production and trade of purple pigments.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
A psychrotrophic XT1 strain (CGMCC 1194) isolated from a glacier in China's Xinjiang province produced violet pigments at a high content. This strain was identified as
Janthinobacterium lividum XT1 ...by API kit and 16S rDNA analysis. The main fraction of violet pigment was violacein based on the analysis by HPLC-MS and
1H NMR. The pigment production by
J. lividum XT1 was not associated with the cell growth, and a cultivation temperature lower than 20
°C was required for the cell growth and pigment production. Sucrose was the most suitable carbon source, and casein was the best nitrogen source for cell growth and pigment formation. Mineral components in the medium, including CaNO
3, FeSO
4, riboflavin, MgSO
4 and nicotinic acid, showed different effects on the cell growth and pigment production. The maximum pigment productivity reached 0.8
g pigment per dry cell weight. The pigment production pattern by our isolate was different from that by other strains such as
J. lividum reported so far.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The aims of this work were to identify and characterize for some important technological properties the yeast species present throughout the ripening process of Pecorino Crotonese, a traditional ...cheese produced in a well defined area of Southern Italy. In particular, the strain technological properties considered include fermentation/assimilation of galactose and lactose, assimilation of lactate and citrate in the presence of different NaCl concentrations, hydrolysis of butter fat, skim milk, gelatine and casein, production of brown pigments in cheese agar and ability to produce biogenic amines. High yeast levels were recorded in cheese samples already after 5
h of brining (about 5
log
cfu/g) and these concentration remained constant during ripening. The yeast isolates belonged to restrict number of yeast species. While
Kluyveromyces lactis and
Saccharomyces cerevisiae were isolated prevalently in the first stages of Pecorino Crotonese production,
Yarrowia lipolytica and
Debaryomyces hansenii dominated during the later stages of maturation. Otherwise, the latter two were very NaCl resistant species. In fact,
D. hansenii strains conserved the ability to assimilate lactose and galactose in the presence of 10% NaCl, while almost all the strains of
Y. lipolytica isolated assimilated citrate and lactate up to 7.5% NaCl.
Y. lipolytica isolates evidenced also the highest proteolytic and lipolytic activities and the capability to catabolize tyrosine producing brown pigment. In addition they resulted in the highest aminobiogenic potential decarboxylating ornithine, phenylalanine, tyrosine and lysine. However, they were not able to produce histamine, biogenic amine produced by three strains of
D. hansenii.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Pigment production, Nanoparticles, Extraction of pyocyanin pigment, and purification of pyocyanin pigment. 1-Introduction Pseudomonas aeruginosa is a significant opportunistic pathogen that ...significantly affects immunocompromised patients and burn victims and induces lung infections in patients with serious underlying diseases such as cystic fibrosis (CF), bronchectasis and chronic obstructive pulmonary disease (1), and possesses a natural resistance to many antibiotics and it causes widespread deaths in immunocompromised patients (2). Preparation of gold nanoparticles (AuNPs): The gold nanoparticles were prepared according to (23) as follows: 1.Preparation stock solution (12 mM) of HAuCl4 Dissolved 1gram of HAuCl4 (99% Germany) in 200 ml distilled water in a flask of 500 ml to obtain a solution of HAuCl4 (12 mM), and it was stored in a brown bottle. 2.Preparation of black tea leaves the solution Using 0.34 gram from black tea leaves in 100 ml of distilled water on the magnetic hot plate for 15 min at 70-80 °C, then filtered with Whatman filter paper No.1. - Synthetic AuNPs were synthesized by reducing HAuCl4 to Au. 100 ml of HAuCl4 solution (12 mM) were mixed with black tea leaves extract (100 ml) on a magnetic stirrer hotplate at 80°C, the color of the mixture turned purple within 10-15 minutes, indicating the production of gold nanoparticles, then sterilize the solution using a filter syringe 0.22pm. Gold nanoparticles have been subject to FTIR analysis to know functional groups of the nanoparticles after being deposited on a glass slide to dry and then mixing them with potassium bromide (KBr) granules at a ratio of 1:100 until they are in the form of a disk, and then the model was measured by (FTIR-4100; Shimadzu-Japan) spectrophotometer (22).
Abstract
Carotenoids represent large group of various natural pigments ensuring typical coloration of plants, microorganisms and several animals. It was confirmed by many studies, that consuming ...these biological active compounds has positive impact for human life. Therefore, they are applied in different industrial fields, such as pharmacy, cosmetic, food, and feed industry. Due to high demand for carotenoids we would like to discover new microorganisms overproducing carotenoids. We focused on yeasts of genus
Rhodotorula sp.
(forty isolates), that we screened according to growth and carotenoid production on Petri dishes and production media. After cultivation on Petri dishes we selected five strains (denoted as KF-4, KF-6, KF-24, KF-31, KF-104) with interesting pigment production and quick growth. The secondary screening on production media identified KF-104 as the best producer of carotenoid pigments with massive pigment accumulation (1.15 mg/g DCW) and yield (9.69 mg/L). The main carotenoid of KF-104 isolate was β-carotene (35.4 %) with the accumulation of 408.7 μg/g DCW and the yield of 3.4 mg/L. The rest were torularhodin, torulene and γ-carotene (62.7–79.0 %). Production of torularhodin in the cells was low (0.4 to 1.4 mg/L) as was its accumulation in cells (31.2–121.0 μg/g DCW). We continue the experimental analyses of these isolates in order understand differences in the content of individual pigments.
Stachybotrys was found to be associated with idiopathic pulmonary hemorrhage in infants in Cleveland, Ohio. Since that time, considerable effort has been put into finding the toxic components ...responsible for the disease. The name Stachybotrys chartarum has been applied to most of these isolates, but inconsistent toxicity results and taxonomic confusion prompted the present study. In this study, 122 Stachybotrys isolates, mainly from water-damaged buildings, were characterized and identified by combining three different approaches: morphology, colony characteristics, and metabolite production. Two different Stachybotrys taxa, S. chartarum and one undescribed species, were found in water-damaged buildings regardless of whether the buildings were in Denmark, Finland, or the USA. Furthermore, two chemotypes could be distinguished in S. chartarum. One chemotype produced atranones, whereas the other was a macrocyclic trichothecene-producer. The second undescribed taxon produced atranones and could be differentiated from S. chartarum by its growth characteristics and pigment production. Our results correlate with different inflammatory and toxicological properties reported for these same isolates and show that the three taxa/chemotypes should be treated separately. The co-occurrence of these three taxa/chemotypes in water-damaged buildings explains the inconsistent results in the literature concerning toxicity of Stachybotrys isolated from that environment.
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BFBNIB, GIS, IJS, KISLJ, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
Phosphomannose isomerases (PMIs) in bacteria and fungi catalyze the reversible conversion of
d
-fructose-6-phosphate to
d
-mannose-6-phosphate during biosynthesis of GDP-mannose, which is the main ...intermediate in the mannosylation of important cell wall components, glycoproteins, and certain glycolipids. In the present study, the kinetic parameters of PMI from
Streptomyces coelicolor
were obtained, and its function on antibiotic production and sporulation was studied.
manA
(SCO3025) encoding PMI in
S
.
coelicolor
was deleted by insertional inactivation. Its mutant (
S
.
coelicolor
∆
manA
) was found to exhibit a
bld
-like phenotype. Additionally,
S
.
coelicolor
∆
manA
failed to produce the antibiotics actinorhodin and red tripyrolle undecylprodigiosin in liquid media. To identify the function of
manA
, the gene was cloned and expressed in
Escherichia coli
BL21 (DE3). The purified recombinant ManA exhibited PMI activity (
K
cat
/
K
m
(mM
−1
s
−1
= 0.41 for
d
-mannose-6-phosphate), but failed to show GDP-
d
-mannose pyrophosphorylase GMP (ManC) activity. Complementation analysis with
manA
from
S
.
coelicolor
or
E
.
coli
resulted in the recovery of
bld
-like phenotype of
S
.
coelicolor
∆
manA
. SCO3026, another ORF that encodes a protein with sequence similarity towards bifunctional PMI and GMP, was also tested for its ability to function as an alternate ManA. However, the purified protein of SCO3026 failed to exhibit both PMI and GMP activity. The present study shows that enzymes involved in carbohydrate metabolism could control cellular differentiation as well as the production of secondary metabolites.
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CEKLJ, DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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