Contamination of mural paintings by indoor airborne fungal spores

Summary The processes of biodeterioration on mural paintings have often been discussed, whereas the causes of contamination have seldom been examined.Many microorganisms responsible for the biodeterioration of paintings are of airborne origin. It follows that an investigation on the aerial microbial concentration and air movements in painted indoors is very useful.This paper reviews the literature of mural painting biodeterioration and the aerobiological studies of painted indoors. Hypogean environments, for their particular microclimatic conditions, are not considered.The fungal species most frequently found in the biodeterioration of wall-paintings are reported, as well as comparisons of surface contamination and aerobiological investigation.This review shows the necessity of finding the best sampling methodologies for cultural heritage studies. The control of airborne contamination and proper sampling methods are highly important in determining treatment strategies for the conservation and prevention of microbial attack on painted surfaces.     

Further studies of crania from ancient northern Africa: an analysis of crania from first dynasty Egyptian tombs, using discriminant functions.

An analysis of First Dynasty crania from Abydos was undertaken using multiple discriminant functions. The results demonstrate greater affinity with Upper Nile Valley patterns, but also suggest change from earlier craniometric trends. Gene flow and movement of northern officials to the important southern city may explain the findings.     

The bacterial aetiology of rosy discoloration of ancient wall paintings

The inventory of microorganisms responsible for biological deterioration of ancient paintings has become an integral part of restoration activities. Here, the microbial agent of rosy discoloration on medieval frescoes in the Crypt of the Original Sin (Matera, Italy) was investigated by a combination of microscopic, molecular and spectroscopic approaches. The bacterial community from three rosy-discoloured painting sites was characterized by 16S rRNA gene-based techniques. The eubacterial population was prevalently composed of Actinobacteria, among which Rubrobacter radiotolerans-related bacteria accounted for 63-87% of the 16S rRNA gene pool per sampled site. Archaea, with prevalence of Haloarchaea-related species, were detected in one of the three sites where they accounted for < 0.1% of the total 16S rRNA gene pool. Raman spectroscopy confirmed the identity between R. radiotolerans carotenoids (bacterioruberins) and pigments responsible for colour alteration of frescoes. This investigation provides the first evidence of a causal relationship between heavy contamination by Rubrobacter-related bacterioruberin-producing bacteria and rosy discoloration of ancient wall paintings.     

Characterization of vascular mural cells during zebrafish development

Development and maturation of the nascent cardiovascular system requires the recruitment of mural cells (MCs) around the vascular tree in a process called vascular myogenesis. Understanding the origin and development of vascular MCs has been hampered by difficulties in observing these cells in vivo and performing defined genetic and experimental manipulations in available model organisms. Here, we investigate the origin of vascular MCs using molecular and genetic tools in zebrafish. We show that vascular MCs are present around the lateral dorsal aortae (LDA) and anterior mesenteric arteries (AMA) of developing animals, and that they also contribute to the outflow tract of the developing heart and ventral aorta (VA). Genetic data indicate that the vascular MCs of the LDA and AMA do not arise from blood or endothelial progenitors but from other derivatives of the lateral plate mesoderm. We further show that zebrafish vascular MCs share many of the morphological, molecular and functional characteristics of vascular smooth muscle cells and pericytes found in higher vertebrates. These data establish the zebrafish as a useful cellular and genetic model to study vascular myogenesis as well as tumor angiogenesis and other MC-associated diseases.     

敦煌壁画色变中微生物因素的研究：Ⅱ.微生物对模拟石窟壁画颜料 …

通过对微生物生长后的模拟壁画的分析测定,发现微生物对壁画颜料有很大影响：微生物形成的可溶性色素直接造成壁画色度的改变,在生长代谢过程中形成大量的草酸盐,并使颜粒晶体的晶形发生变化。此外,微生物的作用使铅丹的价态改变,在铅丹的色变中起着重要的作用。     

Unidirectionality of floral colour changes

Many angiosperms have arranged their flowers in inflorescences forming a distinct signalling unit to flower visitors. In some species, the flowers of inflorescences undergo a temporal colour change corresponding exactly to a change in the reward status. Based on information obtained from the spectral reflection curves of pre-change and postchage colours of flower corollas and/or floral guides, it was possible to demonstrate that the colour phase associated with reward closely corresponds to the visual stimuli which trigger behavioural responses of inexperienced flower visitors, and that the colour phase associated with less reward corresponds to visual stimuli less attractive to naïve flower visitors. Reciprocal colour changes were not observed. It is to be assumed that the unidirectionality of floral colour changes is an adaptation of angiosperms aimed at the guidance of first-time flower visitors. Signalling reward to inexperienced flower visitors is an additional function of floral colour changes. The main function of floral colour changes, however, is to provide cues with which the flower visitors can learn to associate one colour phase with reward.     

Production of transglutaminase by Streptomyces isolates in solid-state fermentation

Aims:  To screen Streptomyces isolates for transglutaminase (TGase) production in solid-state fermentation (SSF) on various substrates.
Methods and Results:  Streptomyces mobaraensis NRRL B-3729, Streptomyces paucisporogenes ATCC 12596 and Streptomyces platensis NRRL 2364 strains were screened for extracellular TGase production in SSF on different substrates. High-protein-content beans, peas and lentils proved to be the best substrates. Good TGase production was obtained on liver kidney beans and green mung beans in a 4- to 6-day SSF. Temperature optima of the enzymes varied between 45 to 50°C. Molecular weight determined by sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS PAGE) indicated similar size (∼37 kDa) for all three enzymes. TGase was the dominating protein band on SDS PAGE for two Streptomyces strains in SSF extracts. Other enzymes were present in smaller quantities.
Conclusions:  Streptomyces mobaraensis NRRL B-3729, S. paucisporogenes ATCC 12596 and S. platensis NRRL 2364 strains were successfully propagated under SSF conditions on crushed/milled liver kidney bean and green mung bean to obtain good level of TGase.
Significance and Impact of the Study:  Owing to much reduced production cost and direct applicability, SSF TGase without downstream processing (cheap in situ enzyme, crude enzyme) may be an excellent candidate for some nonfood applications.     

Distribution of microorganisms on ancient wall paintings as related to associated faunal elements

Knowledge of the bioreceptivity of wall paintings to microbially induced decay processes has increased considerably in the last few years. Indoor wall paintings are widely recognised as a favourable environment for microbial biofilms in general and for microscopic fungi in particular. This environment also provides a suitable substrate for insects, spiders and other arthropodas. A combination of mycological and entomological studies of indoor wall paintings demonstrates an important ecological correlation between fungi and arthropods in the developmental processes of this complex microbial community. The co-existence of microscopic fungi and arthropods on the surface of wall paintings suggests an ecological interaction between them. Faunal impacts on the growth of biofilms due to grazing and propagule dispersal cannot be overlooked. Along with the above-mentioned perturbations, arthropods can directly damage the wall paintings by bioabrasion during grazing on the biofilm, as well as by the production of dwelling cavities. In this publication, we present the ecological connections between the major microscopic inhabitants of these important objects of cultural heritage. The additional role of arthropods as a remarkable source of organic substrate (e.g., chitin, spidersilk and faecal pellets) available for many micromycetes is discussed.     

Production of L-leucine aminopeptidase by selected Streptomyces isolates

Aims: To screen various Streptomyces cultures producing l ‐leucine aminopeptidase (LAP). Methods and Results: Twenty‐one Streptomyces strains were screened for LAP production. The best three producers were found to be Streptomyces mobaraensis NRRL B‐3729, Streptomyces gedanensis IFO 13427, and Streptomyces platensis NRRL 2364. pH optima of the three enzymes were in the range of 8·0–8·5 and the temperature optima varied between 50 and 65°C. LAP of S. mobaraensis was stable at 60°C and pH 8·5 for 60 min. Metal ion salts, CoCl₂.6H₂O and ZnSO₄.7H₂O in 0·7 mmol l^?1 concentration enhanced the relative enzyme activity in all three enzymes. Molecular mass of LAP of S. mobaraensis was found to be approx. 37 kDa. Conclusions: Streptomyces mobaraensis NRRL B‐3729, S. gedanensis IFO 13427, and S. platensis NRRL 2364 were found to be good producers of extracellular LAP. The approx. 37 kDa enzyme of S. mobaraensis is considerably thermostable. Significance and Impact of the Study: A good number of Streptomyces were screened and the ability of the aminopeptidases to release a particular N‐terminal amino acid along with its good thermal stability makes them interesting for controlling the degree of hydrolysis and flavour development for a wide range of substrate.     

Rapid identification of Streptomyces isolates by MALDI-TOF MS

The recent emergence of multidrug-resistant bacteria over the last decade has led to a renewal in the discovery of new antimicrobial drugs. Streptomyces members are practically unlimited sources of new antibiotics. However, the identification of Streptomyces species is difficult and time-consuming. Therefore, there is a need for alternative methods for their rapid identification. In this study, an efficient protocol of identification using Matrix-Assisted Laser Desorption Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF MS) was developed and applied for the rapid identification of Streptomyces isolates from the El Kala lakes in northeastern Algeria. A collection of 48 Streptomyces isolates were used for this study. The optimized procedure allowed us to obtain specific and reproducible protein spectra for each Streptomyces isolate tested. The spectra generated were used to build a preliminary local database based on their initial 16S rRNA identification. The blind test used for the identification of 20 Streptomyces strains already available in our created database and 20 unknown Streptomyces isolates showed that all (100%) of the Streptomyces strains listed in the database were rapidly (<30 min) identified with high scores of up to 2.8. Here, for the first time we showed that MALDI-TOF MS could be used as a cost-effective tool for the rapid identification of Streptomyces isolates.     

Molecular characterisation of Bacillus thuringiensis isolates from the Egyptian soils

Molecular characterisation of nine different Bacillus thuringiensis isolates from the soil of different Egyptian governorates and with varying activities against some lepidopterous insects was carried out using sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE), polymerase chain reaction (PCR) and randomly amplified polymorphic DNA (RAPD)-PCR analysis. Molecular weights of the major components of the crystal proteins of the tested strains revealed that those strains with bands 39 and 141 KDa would be possibly potent against the cotton leafworm Spodoptera littoralis (Biosduval) (Lepidoptera: Noctuidae), those with bands 39–73 and 104–178 KDa showed toxicity against the American bollworm Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) and those with bands 25–3 and 135 KDa may be toxic to the pink bollworm Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae). PCR analysis indicates that the frequency of the cry 1 genes predominated 72.41% of isolates amplifying cry 1 gene. DNA fingerprinting-based randomly amplified polymorphic DNA (RAPD) techniques proved to be a reliable method for identification of different B. thuringiensis strains at the DNA level.     

Characterization of multiple changes of antibiotic resistance characters in Streptomyces coelicolor A3(2)

Among mutants of Streptomyces coelicolor A3(2) studied which were sensitive to chloramphenicol (Cmls), strains sensitive to a number of antibiotics (ristomycin, tetracycline, polymyxin, lincomycin) amount of 46%. Antibiotic-sensitive mutants are capable to form different classes of resistant revertants with frequency varying from 10(-2) to 10(-6) in independent strains. Ristomycin-sensitive clones (Rims) have been found to occur with high frequency in Cmls strains and Cmlr revertants. Mutations mediating the Rims phenotype are mapped in a locus linked to the gene for resistance to chloramphenicol. The results obtained are discussed, in accordance with the notion about possible role of cml mutation in induction of secondary mutational changes in the genome of S. coelicolor A3(2).     

Biodeterioration of mural paintings in a rocky habitat: The Crypt of the Original Sin (Matera, Italy)

The biological colonization of mural paintings in rocky habitats is a widely recurring phenomenon and should be considered for restoration activities. In order to plan conservation treatment of the Crypt of the Original Sin (Matera, Italy), biodeterioration problems were analysed taking into account their impact on the substrate and their relationship with environmental factors. The mural paintings showed a phenomenology of alteration varying from brilliant green, dark green, brown, and black duff patinas with powdery aspect, to rosy discoloration. These phenomena were linked to different microbial colonizations by Cyanobacteria (Chlorogloea microcystoides, Chroococcus lithophilus, Gloeocapsa spp., Gloeothece rupestris, Pseudocapsa dubia) and green algae (Apatococcus lobatus, Chlorella vulgaris, Chlorococcum sp., Muriella terrestris). The rosy discoloration was connected to pigment production by Actinobacteria related to Rubrobacter radiotolerans. Grey-green patinas, limited to more ventilated areas, were caused by lichen growth (Dirina massiliensis f. sorediata). Vascular plants (Adiantum capillus-veneris) were also detected in wall areas affected by rising damp. To control the growth of microflora, biocide treatment and intervention to reduce humidity and sunlight exposure of mural paintings were suggested. To choose the correct biocide, different products were tested, evaluating their efficiency on Cyanobacteria and algae as well as possible effects on the calcarenite stone.     

A brief review of studies and comments on ancient Egyptian biological relationships

A review of studies covering the biological relationship of the ancient Egyptians was undertaken. An overview of the data from the studies suggests that the major biological affinities of early southern Egyptians lay with tropical Africans. The range of indigenous tropical African phenotypes is great; and this range of variation must be considered in any discussion of the Nile Valley peoples. The early southern Egyptians belonged primarily to an African descent group which gained some Near Eastern affinity through gene flow with the passage of time.     

Evidence-based palaeopathology: Meta-analysis of PubMed-listed scientific studies on ancient Egyptian mummies

There is a plethora of published scientific studies on ancient Egyptian mummies. Surprisingly, hitherto there is no systematic review of this research, which would help to assess the quality of this vast body of published literature and thus to increase “evidence” in palaeopathological research. The aim of this study was to review all PubMed-listed scientific studies performed on Ancient Egyptian mummies. A total of 131 studies were found in the database for the selected time period, 1977-2005. Our “meta-analysis” showed that the number of publications per year varies enormously. The majority of mummies examined date to the third intermediate and Ptolemaic periods; data from other time periods were lacking. Identification of the cause of death and ¹⁴C-dating of the mummy or funeral goods were rarely addressed. There was a tendency towards an increased use of non-invasive examination methods in more modern times. Our meta-analysis addressed both scientific content (e.g. palaeopathological findings/examination methods) and publication issues (e.g. location of the first author or year of publication) in these studies. Based on our experience, we recommend some minimum publication standards for palaeopathologic studies on ancient mummies, which shall improve evidence-based research in palaeopathology in general.