Scopelophila Cataractae Research Articles

A novel alpha-glucosidase from the moss Scopelophila cataractae.

Scopelophila cataractae is a rare moss that grows on copper-containing soils. S. cataractae protonema was grown on basal MS medium containing copper. A starch-degrading activity was detected in homogenates of the protonema, after successive extraction with phosphate buffer and buffer containing 3 M LiCl. Buffer-soluble extract (BS) and LiCl-soluble extract (LS) readily hydrolyzed amylopectin to liberate only glucose, which shows that alpha-glucosidase (EC 3.2.1.20) in BS and LS hydrolyzed amylopectin. The K(m) value of BS for maltose was 0.427. The K(m) value of BS for malto-oligosaccharide decreased with an increase in the molecular mass of the substrate. The value for maltohexaose was 0.106, which is about four-fold lower than that for maltose. BS was divided into two fractions of alpha-glucosidase (BS-1 and BS-2) by isoelectric focusing. The isoelectric points of these two enzymes were determined to be 4.36 (BS-1) and 5.25 (BS-2) by analytical gel electrofocusing. The two enzymes readily hydrolyzed malto-oligosaccharides. The two enzymes also hydrolyzed amylose, amylopectin and soluble starch at a rate similar to that with maltose. The two enzymes readily hydrolyzed panose to liberate glucose and maltose (1 : 1), and the K(m) value of BS for panose was similar to that for maltotriose, whereas the enzymes hydrolyzed isomaltose only weakly. With regard to substrate specificity, the two enzymes in BS are novel alpha-glucosidases. The two enzymes also hydrolyzed beta-limit dextrin, which has many alpha-1,6-glucosidic linkages near the non-reducing ends, more strongly than maltose, which shows that they do not need a debranching enzyme for starch digestion. The starch-degrading activity of BS was not inhibited by p-chloromercuribenzoic acid or alpha-amylase inhibitor. When amylopectin was treated with BS and LS in phosphate buffer, pH 6.0, glucose, but not glucose-1-phosphate, was detected, showing that the extracts did not contain phosphorylase but did contain an alpha-glucosidase. These results show that alpha-glucosidases should be capable of complete starch digestion by themselves in cells of S. cataractae.

Contents of heavy metal elements in copper mosses: Scopelophila ligulata, Scopelophila cataractae, and Mielichhoferia japonica and their substrates

Scopelophila ligulata (Spruce) Spruce, S. cataractae (Mitt.) Broth., and Mielichhoferia japonica Besch. (Mielichhoferia mielichhoferi (Hook.) Wijk et Marg. var. japonica (Besch.) Wijk et Marg.) are well known “copper mossess” which show peculiar ecological characteristics consisting of a preference for metal-rich soils, lithosols, rocks, etc. as their substrates. The total and water-soluble element contents in the substrates and heavy metal contents in the moss body were analyzed in this study. The results of these chemical analyses were as follows: The iron contents in the moss body and substrate of S. ligulata were higher than those of S. cataractae and M. japonica. On the contrary the copper contents of the former were lower than those of the latter. The pH values of substrate of S. ligulata were lower than those of S. cataractae and M. japonica. The concentrations of water-soluble iron and sulfate in the substrate of S. ligulata were higher than those of S. cataractae and M. japonica. On the contrary, the water-soluble copper concentrations in the substrate of S. ligulata were lower than those of the others. Although in the substrate of S. cataractae the iron content was several times higher than the copper content, in the moss body the copper content was higher than iron content.

Genetic biogeography of the rate ?copper moss?,Scopelophila cataractae (Pottiaceae)

Scopelophila cataractae, one of the so-called “copper mosses”, has a broad geographic distribution that includes North, Central, and South America, Europe, and Asia, but is rare throughout its range. A genetic analysis of 32 populations from the United States, Europe, and Asia based on 15 putative allozyme loci indicates that levels of genetic diversity vary among geographic regions. Six European populations are fixed for the same alleles at all 15 loci, consistent with the hypothesis thatS. cataractae is a recent immigrant in that region. The species is more diverse in the U.S., where it appears to be native. Five populations collected on copper-enriched soils around shrines and temples in Tokyo are genetically monomorphic, but Asian populations from another Japanese site, India, and Nepal are exceptionally diverse in terms of numbers of alleles and multilocus haplotypes, total gene diversity (HT), and in the degree of differentiation among populations (measured as Nei'sI andD). Long-distance dispersal has probably played an important role in the geographic history ofS. cataractae, but the species appears to be native in both the New and Old Worlds. Gene flow between plants disjunct on different continents is insufficient to explain the lack of geographically correlated morphological and genetic differentiation inS. cataractae.

Population Biology of the Rare Copper Moss, Scopelophila cataractae

The so-called copper mosses include a number of rare species that exhibit very broad intercontinental geographic distributions comprised of highly disjunct occurrences. In one species, Scopelophila cataractae, only the haploid gametophyte generation exists in the United States, although sporophytes occur in tropical America and in Asia. Gametophytic plants were sampled from all U.S. populations to determine what factors limit sexual reproduction. More than 50% of the plants in every population were devoid of gametangia, and no population contained plants with both male and female gametangia. Morphological differences between plants from putative male and female populations (when each was interpreted to be unisexual) suggested gametophytic sexual dimorphism, but generalized sexual differences were not maintained under common garden conditions. Experimental growth of plants on soils with low, moderate, or high concentrations of metals demonstrated extensive morphological variability, and thus genetic polymorphism, among five asexual populations. Morphological traits were also significantly plastic in response to differing soil types, but there was no evidence of differences in patterns of plasticity between sexes or populations. All populations produced higher cover area and individual plants formed larger leaves on the most highly metal-contaminated soil. Populations varied significantly in growth on less contaminated soil, again suggesting genetic variability.

Population biology of the rare copper moss, Scopelophila cataractae

The so‐called copper mosses include a number of rare species that exhibit very broad intercontinental geographic distributions comprised of highly disjunct occurrences. In one species, Scopelophila cataractae, only the haploid gametophyte generation exists in the United States, although sporophytes occur in tropical America and in Asia. Gametophytic plants were sampled from all U.S. populations to determine what factors limit sexual reproduction. More than 50% of the plants in every population were devoid of gametangia, and no population contained plants with both male and female gametangia. Morphological differences between plants from putative male and female populations (when each was interpreted to be unisexual) suggested gametophytic sexual dimorphism, but generalized sexual differences were not maintained under common garden conditions. Experimental growth of plants on soils with low, moderate, or high concentrations of metals demonstrated extensive morphological variability, and thus genetic polymorphism, among five asexual populations. Morphological traits were also significantly plastic in response to differing soil types, but there was no evidence of differences in patterns of plasticity between sexes or populations. All populations produced higher cover area and individual plants formed larger leaves on the most highly metal‐contaminated soil. Populations varied significantly in growth on less contaminated soil, again suggesting genetic variability.

Morphological Uniformity Among Widely Disjunct Populations of the Rare "Copper Moss," Scopelophila cataractae (Pottiaceae)

Eight morphological characters of the gametophyte generation and three of the sporophyte generation were measured in 15 plants from each of 76 populations of the rare and geographically disjunctive moss, Scopelophila cataractae, in order to assess whether subtle differences exist between plants from widely separated populations. Plants were variable in all morphological traits, but most of the variation occurred among individual stems within populations and among populations within broad geographic regions. In spite of statistically significant differences between plants from widely disjunct regions (including different continents) for eight of the 11 morphological traits, the percentage of the total variation attributable to regional differences was minimal. Little regional variation in individual traits was corroborated by multivariate analyses including UPGMA clustering and principal component analysis. Furthermore, the degree and pattern of correlations among morphological traits were remarkably similar in populations of plants separated by thousands of miles. The general rarity and habitat specificity of S. cataractae throughout its range suggest that widely disjunct populations have been continuously separated. This, combined with the present analysis of morphology, suggests that morphological diversification may occur slowly in this moss. Relative to seed plants, most species of have broad geographic ranges. Less than 25% of the of the eastern United States, for example, are endemic even in the broad regional sense, with most taxa occupying remarkably broad ranges that include Europe and/ or Asia (Crum and Anderson 1981; Schuster 1983). Even in floristically rich areas such as the Ozarks, 90% of the are widespread elsewhere in the eastern United States and 70% occur also in the Old World (Crum and Anderson 1981). Indeed, on a worldwide basis, endemism at the specific level is low in mosses. It is common knowledge among moss monographers that many species occur disjunctively on several continents and that there is often little or no morphological differentiation between widely disjunct populations. These systematic and biogeographic observations have led some bryologists to hypothesize that many species of are geologically old and that presently disjunct populations of such species have undergone little or no morphological evolution over vast amounts of time (Crum 1972; Crum and Anderson 1981; Schuster 1983). Arguments in this regard often cite the observation that many intraspecific disjunctions in correspond to the same patterns that occur at the generic level in seed plants. Such patterns (e.g., eastern Asia-eastern North America) have been widely accepted as having derived from fragmentation of the Arctotertiary flora (Herzog 1926; Crum 1972). The likelihood of more recent long-range dispersal has also been discussed for some species (e.g., van Zanten 1984; van Zanten and Pocs 1981). In spite of the common perception of monographers that little morphological differentiation exists between widely disjunct populations of many mosses, there have been few quantitative studies to determine whether subtle patterns of regional variation do in fact occur. The ecologically unique mosses provide an especially good opportunity to address this issue. The copper include about ten species of and liverworts that exhibit an ecological association with substrates with higher than average concentrations of copper or other metals (Persson 1948, 1956; Shacklette 1967). In addition to the unusual habitat of the copper mosses, these species share the characteristic of having remarkably broad and highly disjunctive geographic distributions. Furthermore, most of the copper do not reproduce sexually (as evidenced by sporophyte formation) over large portions of their ranges. One such copper moss, Scopelophila cataractae (Mitt.) Broth., occurs disjunctively in central America and Mexico, the United States, Europe, the Himalayan Mountains, and southeast Asia including the Philippine Islands northward to Japan (Zander 1967). The species is extremely rare throughout its range. In the United States, for example, it occurs at one locality each in

Wave-like protonemal colonies of the mossScopelophila cataractaeand their consequences in light capture

AbstractLight-capture efficiency of the microstructure of protonemal colonies of Scoplophila cataractae, was investigated. Colonies situated at shaded locations and not facing the direction of canopy openings showed a wave-like structure, consisting of mostly parallel laminae extending 2–12 mm from the vertical surface of the substrate. Light irradiance was estimated to be 2.0–2.5 times higher on the upper surfaces of the laminae than on the stone base on which the moss was growing. The wave-like structure is a result of the growth of fibrous protonemal cells perpendicular to the main direction of the incident light. A correlation was found between the height of a lamina and its distance from the adjacent lamina, indicating self-thinning processes during formation of the lamina structure.

Scopelophila cataractae (Mitt.) Broth. in Pennsylvania

The rare copper moss, Scopelophila cataractae was recently collected in the vicinity of a zinc smelter at Palmerton, Pennsylvania. The plants and their substrates were highly enriched with zinc and cadmium, but not copper. Scopelophila cataractae and Anomobryum filiforme are new to Pennsylvania.

Scopelophila cataractae in Texas

Scopelophila cataractae (Mitt.) Broth. is reported for the first time from Texas on a collection from an igneous substrate in Brewster Co., in Big Bend National Park. Small gemmae are borne on branching, green, protonema-like filaments in leaf axils of the Texas plants. Locality records in the United States of Scopelophila cataractae (Mitt.) Broth., a rare copper moss, include Arizona, California, North Carolina, Pennsylvania, and Tennessee (Shaw & Beer 1989). Copper mosses are noted for growing on substrates enriched with metals. The present collection is sterile, as are all others from North America (Shaw & Beer 1989). TEXAS. BREWSTER CO.: Big Bend National Park, Burro Mesa, in Apache Canyon near its head, ca. 29*17'N, 103*25'W, on moist igneous detritus and in seepage cracks below intermittent waterfall, Reese 17344 (BUF, DUKE, LAF, MICH, MO, NY, US). Burro Mesa is largely composed of volcanic material, including lava and ash beds (Maxwell 1968). The general area of the collection site is composed of soft, tuff-like strata with brilliant hues varied from reddish through yellow-orange to violet, perhaps indicative of mineral enrichment. Apache Canyon is relatively remote from human influences today, although it was apparently heavily used by Indians (based on abundant artifactual evidence in the vicinity) and, more recently, by cattle ranchers (Maxwell 1968). Mercury (cinnabar-HgS) mines and smelters-no longer operating-are located in Brewster Co., including one in the Park itself, but there has never been mining activity at Apache Canyon. The nearest mercury mine site is at Study Butte, ca. 11.5 km NW of Apache Canyon. Thus the Apache Canyon population of S. cataractae is growing on a presumably metal-rich subtrate that has not been modified by human activity, as is the case for some locales for this moss. Although protonemal gemmae have apparently not been reported for American material of S. cataractae, they have been reported for this moss from other parts of the world (reviewed by Arts 1988, with illustrations). What may be termed protonemal gemmae (Fig. 1) are produced sparingly on ascending, green, branching, protonema-like structures in leaf axils of the Texas plants; they readily dehisce from the filaments that bear them. The minute gemmae, to ca. 14.5 x 60 #Am, are composed of 1-3 cells in linear arrangement, and have thick walls and dense contents. Some of the larger gemmae are FIGURE 1. Outlines of protonemal gemmae of Scopelophila cataractae (Mitt.) Broth., one still attached to protonemal filament; all from Reese 17344. Scale bar = 50

Scopelophila cataractae(Mitt.) Broth. in North Wales

Abstract Scopelophila cataractae (Mitt.) Broth., discovered in abundance at its third British site, is highly gemmiferous. The plants attain a height of 5 cm, up to twice that previously known, and morphologically differentiated inner perigonial bracts occur. A gametophytic chromosome number of n = 13 is discussed in the wider context of the Pottiaceae.

Copper accumulation and location in the mossScopelophila cataractae

An investigation was carried out on the distribution of a ‘copper moss’ Scopelophila cataractae (Mitt.) Broth in Japan, followed by a semi-quantitative survey of elements present in samples collected using energy-dispersive X-ray fluorescence spectrometry (EDXRF). On the basis of this survey, quantitative studies on the concentrations of Cu and 15 other elements (Na, Mg, AI, P, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, Pb) in the copper-rich samples were carried out using inductively coupled plasma atomic emission spectrometry (ICP-AES). Localization of Cu in the cells was also investigated using scanning and transmission electron microscopy with X-ray microanalysis (SEM-XMA, Cryo-SEM-XMA and TEM-XMA). S. cataractae is able to grow in various copper-rich environments. The concentration of Cu in the shoots attained a level as high as 1–3% although the concentration of Cu in rain water carrying Cu from cooper artifacts to S. cataractae colonies was in the order of ppm. The cell wall was found to be a particularly important site of Cu accumulation in comparison with other cell components.

Evolution of Heavy Metal Tolerance in Bryophytes. II. An Ecological and Experimental Investigation of the "Copper Moss," Scopelophila cataractae (Pottiaceae)

About six bryophyte species (including both mosses and liverworts) are generally thought to be restricted to copper-enriched substrates and are consequently known as “copper mosses.” One of these, Scopelophila cataractae (Pottiaceae), is known from several sites in southern Arizona and occurs at six localities in the eastern United States. Chemical analyses of substrates from the eastern U.S. localities showed that all but one population grew on copper-enriched soil. The one substrate sample low in copper was very high in iron. Plants from five of the six eastern U.S. localities for S. cataractae were grown experimentally on four soil types ranging from highly to not contaminated, and all grew best on the soil contaminated with copper, lead, and zinc. There was no significant variation in growth between populations on the four soil treatments. This lack of population differentiation is in contrast to flowering plants and may be related to the absence of sexual reproduction in S. cataractae in North America.

EVOLUTION OF HEAVY METAL TOLERANCE IN BRYOPHYTES II. AN ECOLOGICAL AND EXPERIMENTAL INVESTIGATION OF THE “COPPER MOSS,” SCOPELOPHILA CATARACTAE (POTTIACEAE)

About six bryophyte species (including both mosses and liverworts) are generally thought to be restricted to copper‐enriched substrates and are consequently known as “copper mosses.” One of these, Scopelophila cataractae (Pottiaceae), is known from several sites in southern Arizona and occurs at six localities in the eastern United States. Chemical analyses of substrates from the eastern U.S. localities showed that all but one population grew on copper‐enriched soil. The one substrate sample low in copper was very high in iron. Plants from five of the six eastern U.S. localities for S. cataractae were grown experimentally on four soil types ranging from highly to not contaminated, and all grew best on the soil contaminated with copper, lead, and zinc. There was no significant variation in growth between populations on the four soil treatments. This lack of population differentiation is in contrast to flowering plants and may be related to the absence of sexual reproduction in S. cataractae in North America.

Scopelophila cataractae(Mitt.) Broth. in South Wales, New to Europe

<i>Scopelophila cataractae</i>(Mitt.) Broth. in South Wales, New to Europe