Thermophilic Actinomycetes Research Articles

Home humidifier thermophilic actinomycete isolates

Twenty-seven thermophilic actinomycete isolates obtained from humidification systems or living-bedroom areas of individuals with suspected but unproved home environment-related respiratory disease were characterized morphologically and biochemically. All isolates were demonstrated to be members of the Thermoactinomyces genus. Two preriously misidentified isolates were reclassified as a Thermoactinomyces sp. Thus, all of our thermophilic actinomycete humidifier isolates studied to date have been identified as either Thermoactinomyces vulgaris or Thermoactinomyces sp. Large numbers of unidentified thermotolerant bacteria have also been isolated from virtually all residual humidifier water samples and their possible role in production of “humidifier-associated” respiratory disease is unknown.

Role of sulfhydryl group in the structure and function of alkaline proteases from a thermophilic actinomycete, Streptomyces rectus var. proteolyticus.

Thermophilic actinomycetes are generally defined as a group of actinomycetes which grow well above 50°C (1). It is well known that they are widely distributed in nature, inhabiting soils, composts, hay, peat, etc., and play an important role in the decomposition of organic matters.In the past decade, a considerable attention has been paid to them as active producers of thermostable extracellular enzymes such as amylase, protease, cellulase, and cell wall lytic enzymes. As for proteolytic enzymes, most of them so far studied are alkaline proteases which are produced by several species belonging to the genera Streptomyces (2–4), Thermoactinomyces (5–14), Thermomonospora (10), and Micropolyspora (15, 16).KeywordsSulfhydryl GroupAlkaline ProteaseNative EnzymeGuanidine HydrochlorideRelay SystemThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

A quantitative study on the activation of the alternative pathway of complement by mouldy hay dust and thermophilic actinomycetes.

Materials associated with the induction of farmer's lung were incubated with fresh normal human serum in the presence of magnesium ethylene glycol tetra-acetic acid (MgEGTA) or ethylene diamine tetra-acetic acid (EDTA) and results compared with material known to activate the alternative pathway of complement--zymosan. Results show that Micropolyspora faeni organisms are as active as zymosan in reducing complement (C) levels in the presence of MgEGTA, with a 50% reduction in CH50 at approximately 140 mug/ml. Thermoactinomyces vulgaris organisms produced a 50% CH50 reduction at approximately 1-25 mg/ml and two samples of respirable mouldy hay dust (MHD) at approximately 5-6 mg/ml whereas extracts of M. faeni and T. vulgaris reduced the CH50 titre by 17% and 39% respectively at 16 mg/ml in the presence of MgEGTA. Organisms and extracts did not reduce the CH50 titre in the presence of EDTA even at the maximum concentration quoted by more than 3%, thus it is considered that alternative pathway activation was responsible for C utilization in the presence of MgEGTA. Respirable MHD used less than 4% available C at 4 mg/ml in the presence of EDTA but at 8 mg/ml dust 11% and 28% available CH50 were used compared with 79% and 81% respectively in the presence of MgEGTA. The elution of immunoglobulin binding material from MHD may be responsible for apparent CH50 consumption in the presence of EDTA.

Partial characterization of a thermophilic actinomycete rennin.

The thermophilic rennin isolated from a thermophilic actinomycete which was described previously by Laxer et al. (1972) and Pinsky et al. (1973) was further purified and characterized.

Properties of proteolytic enzymes isolated from a thermophilic strain of Micromonospora vulgaris 42

Two proteolytic enzymes, protease A and protease B, were isolated in homogeneous state from the cultural broth of the thermophilic actinomycete Micromonospora vulgaris 42. Their physicochemical properties were studied, i.e., molecular weight (50 000 for protease A and 30 000 for protease B), amino acid composition, N-terminal amino acids (phenylalanine for protease A and alanine for protease B). The specificity of the action of these enzymes was assayed by splitting the B chain of oxidized insulin. Both enzymes are neutral proteases of the thermolysine type.

Experimental production of granulomatous pneumonitis: Comparison of immunological and morphological sequelae with particulate and soluble antigens administered via the respiratory route

Rabbits were sensitized with either a soluble protein antigen (BSA) or a particulate thermophilic actinomycete antigen ( Micropolyspora faeni) via the respiratory route, followed by monitoring of sequential morphologic changes and the humoral plus cellular immunologic response. Primary respiratory tract sensitization with BSA resulted in a humoral anti-BSA response, Arthus and delayed skin reactivity, and in some cases specific antigen-induced alveolar macrophage migration inhibition, all in the absence of pulmonary lesions. Lesions characterized by mild multifocal perivascular mononuclear cell infiltrates in the lungs developed only after secondary BSA aerosol challenge. In contrast to these findings, “primary” respiratory tract sensitization with M. Faeni particulate antigen in saline solution resulted in the gradual development of extensive and progressive pulmonary interstitial and alveolar mononuclear cell infiltrates. These lesions were uniformly associated with specific serum precipitating antibody and delayed skin reactivity. Alveolar macrophage migration was significantly inhibited by Micropolyspora faeni in virtually of these animals. These results, while not excluding a primary irritant effect or Type II or III allergic tissue injury, suggest a role for delayed (cell-mediated) hypersensitivity in the pathogenesis of particulate actinomycete-induced pulmonary lesions. They also indicate that primary immunization with soluble purified protein antigens via the respiratory route can lead to systemic humoral and cell-mediated immunity without production of pulmonary lesions.

Characterization of types of enzymatic activity in somatic extracts of selected fungi, thermophilic actinomycetes and pollen by immunoelectrophoresis.

Characterization of types of enzymatic activity in somatic extracts of selected fungi, thermophilic actinomycetes and pollen by immunoelectrophoresis.

Actinomycetes Are Bacteria

To the Editor.— A case of hypersensitivity alveolitis in an 11-year-old girl was recently reported by Marinkovich and Hill (231:944, 1975) as being caused by a thermophilic actinomycete. Actinomycetes are bacteria and not molds as the authors stated.

A scheme for the identification of thermophilic actinomycetes associated with hypersensitivity pneumonitis.

A scheme has been developed for the identification of thermophilic actinomycetes associated with hypersensitivity pneumonitis. Eighty strains, 10 Micropolyspora faeni, 6 Saccharomonospora viridis, 52 Thermoactinomyces candidus, 7 T. vulgaris, 4 T. sacchari, and 1 T. dichotomica, either isolated from patients' environment or received as authentic strains, were studied. In addition to the cultural and microscopic morphology in various media, each strain was subjected to an array of biochemical tests. These tests included decomposition of tyrosine, xanthine, hypoxanthine, gelatin, casein, esculin, and arbutin. Using a rapid thin-layer chromatography method, the isomer of diaminopimelic acid and sugar in the whole cell hydrolysate were studied. The thermophilic actinomycetes can be identified in a reasonable period of time using a combination of all these tests.

Growth and Sporulation of Thermophilic Fungi and Actinomycetes in O2-N2 Atmospheres

Growth and Sporulation of Thermophilic Fungi and Actinomycetes in O2-N2 Atmospheres

Precipitating antibodies in office workers and hospitalized patients directed toward antigens causing hypersensitivity pneumonitis.

The frequency of precipitating antibodies to Aspergillus, thermophilic actinomycetes, and pigeon serum was studied in hospitalized patients and in employees of the state of Wisconsin. Precipitins to Aspergillus were detected in 9 per cent of the hospitalized patients and 3 per cent of the state employees. The majority of the serologically reactive hospitalized patients were diagnosed as having carcinoma with metastases, lymphoma, or leukemia. No evidence of hypersensitivity pneumonitis or invasive aspergillosis was seen in these patients. The frequency of antibodies to thermophilic actinomycetes (3 per cent) and pigeon serum (1 per cent) was similar in both groups. Women from 17 to 25 years of age and men from 52 to 66 years of age demonstrated an increased incidence of positive precipitins.

Amylase of the thermophilic actinomycete Thermomonospora vulgaris

Abstractα‐Amylase of the thermophilic actinomycete Thermomonospora vulgaris was partially purified. Maximal enzyme activity was obtained at 60 °C and pH 6.0. KM value was 1.4%. The effect of some metal salts on enzyme activity was studied. Enzyme activity was inhibited by KCN, EDTA, and iodoacetate. Inhibition by EDTA was completely nullified by CaCl2, but the inhibition by iodoacetate was not overcome by 2‐mercaptoethanol. Exposure of the enzyme to pH 7.0 and 9.0 for 2hr. did not affect the enzyme, but exposure to pH 3.0 for few minutes completely inactivated the enzyme. Exposure of the enzyme to 60 °C resulted in an appreciable inactivation and exposure to 80 °C completely inactivated the enzyme. Addition of CaCl2, 2‐mercaptoethanol, or enzyme substrate did not stabilize the 60 °C exposed enzyme. However, bovine serum albumin had a protective effect when the enzyme was exposed to 60 °C but not to 80 °C. The enzyme was stable in the presence of 8 M urea.

Amylase of the thermophilic actinomycete Thermomonospora vulgaris.

alpha-Amylase of the thermophilic actinomycete Thermomonospora vulgaris was partially purified. Maximal enzyme activity was obtained at 60degreeC and pH 6.0. KM value was l.4%. The effect of some metal salts on enzyme activity was studied. Enzyme activity was inhibited by by KCN, EDTA, and iodoacetate. Inhibition by EDTA was completely nullified by CaCl2, but the inhibition by iodoacetate was not overcome by 2-mercaptoethanol. Exposure of the enzyme to pH 7.0 and 9.0 for 2 hr. did not affect the enzyme, but exposure to pH 3.0 for few minutes completely inactivated the enzyme. Exposure of the enzyme to 60degreeC resulted in an appreciable inactivation and exposure to 80degreeC completely inactivated the enzyme. Addition of CaCl2, 2-mercaptoethanol, or enzyme substrate the 60degreeC exposed enzyme. However, bovine serym albumin had a protective effect when the enzyme was exposed to 60degreeC but not to 80degreeC. The enzyme was stable in the presence of 8 M urea.

Epidemiologic studies relating thermophilic fungi and hypersensitivity lung syndromes.

This study reviews the potential relationship between exposure to thermophilic actinomycetes and hypersensitivity pneumonitis. Two hundred and seventy-two subjects were studied; they included 85 symptomatic subjects, 96 related control subjects, and 91 nonrelated control subjects: Positive cultures for Thermoactinomyces vulgaris were found in 69 of 93 suspect homes (74 per cent) and in 32 of 64 control homes (50 per cent) (difference significant). The suspect subjects, by definition, ·had a greater incidence of respiratory symptoms than all other groups. Precipitating antibodies against various thermophilic antigens were found with higher frequency among symptomatic sub­ jects (P < 0.01). No direct correlation was found among symptoms, wentgenographic findings, and the presence of precipitating antibodies.

Growth of Thermomonospora fusca on lignocellulosic pulps of varying lignin content.

The ability of the thermophilic actinomycete, Thermomonospora fusca, to degrade lignocellulose was investigated. Thermomonospora fusca was grown at 55C on lignocellulosic pulps varying in lignin content between 3% and 18%. Thermomonospora fusca was found to degrade primarily the carbohydrate fraction of these substrates. Small, and probably insignificant, losses of lignin were observed after 14 days growth on the substrates. Increasing lignin content in the pulps proportionally blocked carbohydrate utilization by T. fusca. The organism, however, could still substantially solubilize even the substrate containing 18% lignin. It is thought that T. fusca plays a role in the decomposition of lignocellulose in nature; however, it is probably involved with carbohydrate degradation, not lignin degradation.

Cross reactions to antigens causing hypersensitivity pneumonitis

The sera of patients with asthma, aspergillosis, pigeon breeder's disease, farmer's lung, and a hypersensitivity pneumonitis in textile plant workers were screened by gel diffusion against a variety of fungal antigens and dust extracts. Patients with hypersensitivity pneumonitis were especially prone to develop precipitating antibody to numerous airborne antigens. From the results it was concluded that patients with hypersensitivity pneumonitis form precipitating antibodies to definite groups of antigens in their environment. Most of the patients had precipitins to house dust that formed lines of identity with fungi and thermophilic actinomycetes.

Serologic studies in farmer's lung. Precipitins to the thermophilic actinomycetes.

Two separate studies were conducted to determine the incidence of antibodies to different isolates of the thermophilic aotinomycetes in patients with fanner's lung. Micropolyspora fa!eni accounted for slightly more than one-half of the sensitization, but sensitivity to more than I antigen was also seen. The most frequent combination was M. faeni and Thermomonospora viridis. It also appears that Thermoactinomyces vulgaris strains differ in antigenicity. Three strains of T. vulgaris tested differed, and currently all are in use as test reagents. The recommendation is made that testing for farmer's lung, particularly on a screening basis, include as a minimum, M. faeni, T. vulgaris (3 strains), T. viridis, Thermoactinomyces sacchari, and the air conditioner microorganism.

Biological and biochemical studies on a keratinolytic thermo philic actinomycete, isolated from Egyptian soil

A thermophilic actinomycete was isolated from Egyptian soil by an enrichment technique. The organism was identified as a strain of Thermomonospora vulgaris , capable of d gesting native as well as autoclaved keratin (chicken feather). The effect of some factors on the growth of the organism and the percentage of feather hydrolysis was examined. A possible mechanism for keratin hydrolysis was discussed.

Moulding of sugar‐cane bagasse and its prevention

SUMMARYWhen fresh sugar‐cane bagasse containing about 50% water and 3% sugar was baled and stacked, it quickly heated to over 50°C and remained hotter than 40°C for 50 days. The residual sucrose was utilized by microbial growth and the content of fungal, bacterial and actinomycete spores increased to more than 108/g dry wt. The spores in heated bagasse were mostly of thermophilic actinomycetes and fungi, and included two actinomycetes implicated in bagassosis. Thermoactinomycetes sacchari occurred in 40% of samples examined, some of which yielded up to 5 × 106 colonies/g, while T. vulgaris occurred in 80% of samples, but these rarely yielded more than 105 colonies/g. Other organisms were cellulolytic and caused fibre deterioration. Heating and moulding could be much decreased either by drying to about 25% water content, which halved the spore content after storage, mostly at the expense of the actinomycetes, or by adding 2% by weight of propionic acid, which decreased the spore content to 4 × 106 spores/g or less even after 18 months' storage. Sometimes adding only 0·6% of propionic acid or 2% of propionic acid applied as a 50% aqueous solution had a similar effect. Treatment with propionic acid thus decreased the deterioration of bagasse, permitted its storage between harvests and prevented the hazard of bagassosis to workers.

Precipitating Antibodies Against Organic Dust Antigens in Human Sera by Counterimmunoelectrophoresis

Serum precipitating antibodies against certain organic dusts and fungi are thought to play a role in pathogenesis of hypersensitivity pneumonitis, allergic bronchopulmonary aspergillosis, and possibly “late onset” bronchial asthma by means of complement mediated hypersensitivity reactions, but nothing is known concerning their possible presence in the population at large. We employed the technique of counterimmunoelectrophoresis to determine their incidence in groups of “atopic” asthmatic and “nonatopic” normal individuals. A high incidence of precipitins was demonstrated in all subject categories against ubiquitous organic dust antigens which included several house dust preparations, a locally prevalent vegetable dust, a thermophilic actinomycete and human dandruff. Precipitins against a seasonal pollen antigen (giant ragweed) were only occasionally detected. These data provide the first evidence that antiorganic dust IgG serum precipitins are frequently present in the population at large. Our findings likely reflect the normal host response to prolonged environmental inhalant organic dust exposure. The biologic significance of antiorganic dust serum precipitins is unknown but their presence per se cannot be considered as evidence of pulmonary disease.