Pulmonary cavities colonized by actinomycetes: report of six cases

Six cases of a cavitary pulmonary ball formed by Actinomycetes are reported. They were observed in the state of Bahia, Brazil. All patients complained of cough and hemoptysis and the pathological study showed bronchiectasis and small cavities in the lungs. The lesions contained micro-colonies of Actinomyces, identified by morphology, staining properties and culture in two cases (thioglycolate media). In the six patients the disease was limited to the lungs. In one patient grains were found, within micro-abscesses in the surrounding parenchyma. Probably the invasion occurred due to ulceration of bronchial mucosa that was covered by granulation tissue. The author suggests that as in nocardiosis actinomycosys may have an invasive form, a saprophytic one may and colonize pulmonary cavities.

Antiviral property of marine actinomycetes against White Spot Syndrome Virus in penaeid shrimps

Aquaculture farms, particularly in Southeast Asia are facing severe crisis due to increasing incidences of White Spot Syndrome Virus (WSSV). Actinomycetes have provided many important bioactive compounds of high prophylactic and therapeutic value and are continually being screened for new compounds. In this communication, the results of a study made to determine the effectiveness of marine actinomycetes against the white spot disease in penaeid shrimps are presented. Twenty-five isolates of actinomycetes were tested for their ability to reduce infection due to WSSV among cultured shrimps. When these actinomycetes were made available as feed additives to the post-larvae of the black tiger shrimp Penaeus monodon for two weeks and challenged with WSSV, the post challenge survival showed variations from 11 to 83%. However, six isolates have shown to be the most potential candidates for further study.

Marine Actinomycetes as Source of Antiviral Agents and as Probionts for Penaeus monodon Culture Systems

The present study revealed the importance of marine actinomycetes as a potent source of bio active secondary metabolites. The selected isolates were capable of protecting Peaneus monodon against WSSV infection. They also proved to be inhibitory to vibrios and is a rich pool of hydrolytic enzymes. Their capacity to proliferate in saline environments and their property of non-pathogenicity to prawns makes them good candidates to be applied as probionts in penaeid shrimp aquaculture. They also enhanced the immune status of shrimps challenged with WSSV and act as a good source of antioxidants. Exploitation of the potential for the prophylactic and therapeutic measures in aquatic animal health management would be highly rewarding. This work is a preliminary study targeting marine actinomycetes as a source of antiviral compounds and as probionts in Penaeus monodon culture systems. More work is needed to understand the nature and mode of action of the bioactive compound, the various aspects of immune and antioxidant responses under challenge and when exposed to pro active treatments, and the dose and frequency of application of such compounds under rearing conditions.

Marine Actinomycetes as Source of Antimicrobial Compounds and as Probiotics and Single Cell Protein for Application in Penaeid Prawn Culture Systems

This thesis Entitled Marine actinomycetes as source of antimicrobial compounds and as probiotics and single cell protein for application in penaeid peawn culture systems. Ocean harbours more than 80% of all life on earth and remains our greatest untapped natural resource. The study revealed the potential of marine actinomycetes as a source of antimicrobial compounds. The selected streptomycetes were found to be capable of inhibiting most of the pathogenic vibrios, whichis a major problem both in hatcheries and grow out systems. The bioactive principle can be incorporated with commercial feeds and applied as medicated diet for the control of vibrios in culture systems.The hydrolytic potential inhibitory property against pathogens and non—pathogenicity to penaeid prawns make the selected Streptomycesspp.an effective probioic in aquaculture. Since there is considerably less inhibition to the natural in pond ecosystem the microbial diversityis being maintained and thereby the water quality. Actinomycetes was found to be a good source of single cell protein as an ingredient inaquaculture feed formulations. Large amount of mycelial waste (actinomycete biomassO is produced from antibiotic industries and this nutrient rich waste can be effectively used as a protein source in aquaculture feeds.This study reveals the importance of marine actinomycetes as a source of antimicrobial compounds and as a probiotic and single cell protein for aquaculture applications.

Distribution and bioactive potential of soil actinomycetes from different ecological habitats

Emergence of drug resistance among pathogenic bacteria to currently available antibiotics has intensified the search for novel bioactive compounds from unexplored habitats. In the present study actinomycetes were isolated from two relatively unexplored and widely differing habitats such as mountain and wetlands and their ability to produce antibacterial substances were analyzed. Pure cultures of actinomycetes were identified by morphological and biochemical tests. Various genera of actinomycetes encountered included Nocardia, Pseudonocardia, Streptomyces, Nocardiopsis, Streptosporangium, Micromonospora, Rhodococcus, Actinosynnema, Nocardiodes, Kitasatosporia, Gordona, Intrasporangium and Streptoalloteichus. The frequency of occurrence of each genus was found to vary with sample. About 47% of wetland isolates and 33% of mountain isolates were identified as various species of Nocardia. The isolated strains differed among themselves in their ability to decompose proteins and amino acids and also in enzyme production potential. Antibiotic activities of these actinomycetes were evaluated against 12 test pathogenic bacteria by well diffusion method using agar wells in glycerol-yeast extract agar. About 95% of actinomycete isolates from wetland ecosystem and 75% of highland isolates suppressed in different degrees the growth of test pathogens. Relatively high antibacterial activity among these isolates underlined their potential as a source of novel antibiotics.

Diversity of Bacillus And Actinomycetes in the water and sediment samples from Kumarakom region of Vembanadu lake

Diversity of different groups of Bacillus and Actinomycetes in the water and sediment samples from kumarakom estuary was analysed to find out potential strains for further application. Bacillus genera was identified and grouped into five phenogroups .Phenogroups show differences in the shape of the spore,position of the spore,and swelling of the sporangium.Ability of the isolates to elaborate various hydrolytic enzymes and their ability to reduce nitrate and ferment various carbohydrate sources were also studied.

Biochemical and physiological characteristics of actinomycetes isolated from high altitude shola soils of tropical Montane forest

Actinomycetes are gram-positive, free-living, saprophytic bacteria widely distributed in soil, water and colonizing plants showing marked chemical and morphological diversity. They are potential source of many bioactive compounds, which have diverse clinical effects and important applications in human medicine. In the present work, we have studied some of the physiological and biochemical characteristics of 36 actinomycete strains isolated from the shola soils of tropical montane forest; a relatively unexplored biodiversity hotspot. Ability of actinomycetes isolates to ferment and produce acids from various carbohydrate sources such as innositol, mannose, sorbitol, galactose, mannitol, xylose, rhamnose, arabinose, lactose and fructose were studied. Almost all the carbon compounds were utilized by one or other actinomycete isolates. The most preferred carbon sources were found to be xylose (94.44%) followed by fructose and mannose (91.66%). Only 41.76% of the isolates were able to ferment lactose. The ability of actinomycetes isolates to decompose protein and amino acid differ considerably. 72.22% of the isolates were able to decompose milk protein casein and 61.11% of the isolates decompose tyrosine. Only 8.33% of the strains were able to decompose amino acid hypoxanthine and none of them were able to decompose amino acid xanthine. Potential of the actinomycetes isolates to reduce esculin, urea and hippurate and to resist lysozyme was also checked. 91.66% of the isolates showed ability to decompose esculin and 63.88% of the isolates had the capacity to produce urease and to decompose urea. Only 25% of the isolate were able to decompose hippurate and 94.44% showed lysozyme resistance

SPATIOTEMPORAL VARIATION AND ANTIBACTERIAL ACTIVITY OF ACTINOMYCETES ISOLATED FROM HIGH ALTITUDE GRASSLAND SOILS OF TROPICAL MONTANE FOREST – KERALA, INDIA

TThe invention of novel antibiotics and other bioactive microbial metabolites continues to be an important aim in new drug discovery programmes. Actinomycetes have the potential to synthesize lots of diverse biologically vigorous secondary metabolites and in the last decades actinomycetes became the most productive source for antibiotics. Therefore in the present study we analyze the antibacterial activity of the actinomycetes isolated from grassland soil samples of Tropical Montane forest. A total of 33 actinomycete strains isolated were characterized and screened for antibacterial activities using well diffusion method against six specific pathogenic organisms. Identification of the isolates revealed that the majority of them were belonging to Streptomycetes followed by Nocardia, Micromonospora, Pseudonocardia, Streptosporangium, Nocardiopsis and Saccharomonospora. Among the 33 isolates, Gr1 strain showed antagonistic activity against all checked pathogens. Nine strains showed antibacaterial activity against Listeria, Vibrio cholera, Bacillus cereus, Staphylococcus aureus and Salmonella typhi and only 2 strains (Gr1and Gr25) showed antagonism to E. coli. The overall percentage of activity of actinomycetes isolates against each pathogenic bacterium was also calculated. While 63.63% of the actinomycetes were antagoinistic against Listeria, Vibrio cholerae, and Bacillus cereus, 60.6% of them were antagonistic to Staphylococcus aureus. Very few isolates (6.06%) showed antibacterial activity against E. coli. In general most of the actinomycetes isolates were antagonistic to grampositive bacteria such as Listeria, Bacillus and Staphylococcus than Gram-negative bacteria Vibrio cholerae, E. coli and Salmonella

Occurrence of hyphomycetes and actinomycetes in red-yellow latosol from a cerrado region in Brazil

A study to quantify the populations of filamentous fungi and actinomycetes was undertaken in a cerrado area, in Corumbatai county, São Paulo, at different depths of medium-textured red-yellow latosol, correlating them to humidity, organic matter, pH of the soil and climatic factors. The technique used was the serial dilution of composite soil samples (n=4), using Martin's medium with streptomycin for filamentous fungi and a starch medium for actinomycetes. The number of filamentous fungi was more abundant in the first soil layer, 0-5 cml compared to the other depths. The number of actinomycetes was higher between 5 cm and 50 cm depth. There were two-monthly variations in the number of filamentous fungi and actinomycetes. A sharp drop in fungi was found in May 1988 at all depths of the soil, when there was lower air temperature and an atypically high monthly rainfall for this period in the cerrado. Statistically significant and directly proportional correlations were obtained between the number of actinomycetes and the rainfall at depths of 0 to 5 cm and 50 to 100 cm. The results obtained in the different soil layers to 100 cm depth demonstrated the importance of the first 5 cm layer due to the heavy concentration of microorganisms, mainly the filamentous fungi, together with the highest organic matter content.

Streptomyces brevispora sp nov and Streptomyces laculatispora sp nov., actinomycetes isolated from soil

The taxonomic positions of two actinomycetes isolated from a hay meadow soil sample were determined using a polyphasic approach. The isolates had chemical and morphological properties typical of streptomycetes and formed a distinct 16S rRNA gene subclade together with the type strain Streptomyces drozdowiczii NRRL B-24297(T). DNA DNA relatedness studies showed that the three strains belonged to different genomic species. The organisms were also distinguished using a combination of phenotypic properties. On the basis of these data it is proposed that the isolates be assigned to the genus Streptomyces as Streptomyces brevispora sp. nov. and Streptomyces laculatispora sp. nov., with BK160(T) (=KACC 21093(T) =NCIMB 14702(T)) and BK166(T) (=KACC 20907(T) =NCIMB 14703(T)) as the respective type strains.

Amycolatopsis thermophila sp nov and Amycolatopsis viridis sp nov., thermophilic actinomycetes isolated from arid soil

The taxonomic positions of two thermophilic actinomycetes isolated from an arid Australian soil sample were established based on an investigation using a polyphasic taxonomic approach. The organisms had chemical and morphological properties typical of members of the genus Amycolatopsis and formed distinct phyletic lines in the Amycolatopsis methanolica 16S rRNA subclade. The two organisms were distinguished from one another and from the type strains of related species of the genus Amycolatopsis using a range of phenotypic properties. Based on the combined genotypic and phenotypic data, it is proposed that the two isolates be classified in the genus Amycolatopsis as Amycolatopsis thermophila sp. nov. (type strain GY088(T)=NCIMB 14699(T)=NRRL B-24836(T)) and Amycolatopsis viridis sp. nov. (type strain GY115(T)=NCIMB 14700(T)= NRRL B-24837(T)).

Amycolatopsis granulosa sp nov., Amycolatopsis ruanii sp nov and Amycolatopsis thermalba sp nov., thermophilic actinomycetes isolated from arid soils

The taxonomic positions of three thermophilic actinomycetes isolated from arid soil samples were established by using a polyphasic approach. The organisms had chemical and morphological features that were consistent with their classification in the genus Amycolatopsis. 16S rRNA gene sequence data supported the classification of the isolates in the genus Amycolatopsis and showed that they formed distinct branches in the Amycolatopsis methanolica subclade. DNA-DNA relatedness studies between the isolates and their phylogenetic neighbours showed that they belonged to distinct genomic species. The three isolates were readily distinguished from one another and from the type strains of species classified in the A. methanolica subclade based on a combination of phenotypic properties and by genomic fingerprinting. Consequently, it is proposed that the three isolates be classified in the genus Amycolatopsis as representatives of Amycolatopsis granulosa sp. nov. (type strain GY307(T)=NCIMB 14709(T)=NRRL B-24844(T)), Amycolatopsis ruanii sp. nov. (type strain NMG112(T)=NCIMB 14711(T)=NRRL B-24848(T)) and Amycolatopsis thermalba sp. nov. (type strain SF45(T)=NCIMB 14705(T)=NRRL B-24845(T)).

The gastric caeca of pentatomids as a house for actinomycetes

Abstract Background Microbes are extensively associated with insects, playing key roles in insect defense, nutrition and reproduction. Most of the associations reported involve Proteobacteria. Despite the fact that Actinobacteria associated with insects were shown to produce antibiotic barriers against pathogens to the hosts or to their food and nutrients, there are few studies focusing on their association with insects. Thus, we surveyed the Actinobacteria diversity on a specific region of the midgut of seven species of stinkbugs (Hemiptera: Pentatomidae) known to carry a diversity of symbiotically-associated Proteobacteria. Results A total of 34 phylotypes were placed in 11 different Actinobacteria families. Dichelops melacanthus held the highest diversity with six actinobacteria families represented by nine phylotypes. Thyanta perditor (n = 7), Edessa meditabunda (n = 5), Loxa deducta (n = 4) and Pellaea stictica (n = 3) were all associated with three families. Piezodorus guildini (n = 3) and Nezara viridula (n = 3) had the lowest diversity, being associated with two (Propionibacteriaceae and Mycobacteriaceae) and one (Streptomyceataceae) families, respectively. Corynebacteriaceae and Mycobacteriaceae were the most common families with phylotypes from three different insect species each one. Conclusions Many phylotypes shared a low 16S rRNA gene similarity with their closest type strains and formed new phyletic lines on the periphery of several genera. This is a strong indicative that stinkbug caeca can harbor new species of actinobacteria, which might be derived from specific associations with the species of stinkbugs studied. Although the well-known role of actinobacteria as a source of biomolecules, the ecological features of these symbionts on the stinkbugs biology remain unknown.