In the Zambales ophiolite range, terrestrial serpentinizing fluid seeps host diverse microbial assemblages. The fluids fall within the profile of Ca2+-OH−-type waters, indicative of active serpentinization, and are low in dissolved inorganic carbon (DIC) (<0.5 ppm). Influx of atmospheric carbon dioxide (CO2) affects the solubility of calcium carbonate as distance from the source increases, triggering the formation of meter-scale travertine terraces. Samples were collected at the source and along the outflow channel to determine subsurface microbial community response to surface exposure. DNA was extracted and submitted for high-throughput 16S rRNA gene sequencing on the Illumina MiSeq platform. Taxonomic assignment of the sequence data indicates that 8.1% of the total sequence reads at the source of the seep affiliate with the genus Methanobacterium. Other major classes detected at the source include anaerobic taxa such as Bacteroidetes (40.7% of total sequence reads) and Firmicutes (19.1% of total reads). Hydrogenophaga spp. increase in relative abundance as redox potential increases. At the carbonate terrace, 45% of sequence reads affiliate with Meiothermus spp. Taxonomic observations and geochemical data suggest that several putative metabolisms may be favorable, including hydrogen oxidation, H2-associated sulfur cycling, methanogenesis, methanotrophy, nitrogen fixation, ammonia oxidation, denitrification, nitrate respiration, methylotrophy, carbon monoxide respiration, and ferrous iron oxidation, based on capabilities of nearest known neighbors. Scanning electron microscopy and energy dispersive X-ray spectroscopy suggest that microbial activity produces chemical and physical traces in the precipitated carbonates forming downstream of the seep's source. These data provide context for future serpentinizing seep ecosystem studies, particularly with regards to tropical biomes.

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Exiguobacterium sp. AB2 is a haloalkaliphilic bacterium isolated from a hyperalkaline spring in Manleluag, Pangasinan, Philippines. Sequencing of bacterial DNA assembled a 2.85 MB draft genome. Analysis suggests the presence of genes for tolerance to stresses such as elevated pH and salt concentrations and toxic metals.

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Distribution of glucose and mannose moieties of Acanthamoeba sp. (W4) Philippine isolate was detected using fluorescem isothiocyanate (FITC)- labeled Concannavalin A (Con A) lectin. Green fluorescent patches around the plasma membrane of agglutinated trophozoites (Fig.1) were observed. Isolated Acanthamoeba cyst exhibited strong fluorescence on the cyst wall Brighter fluorescence was detected on the site of adherence between the Acanthamoeba (W4) cysts and trophozoites (Fig. 1,3). These lectin receptors were concentrated at the uroidal region of the trophozoite. The fluorescence, however, was absent in the newly forming hyaline cap (Fig.4). Upon addition of α -methyl-mannoside (0.5 M), Con A binding to sugar moieties in cyst and trophozoites was blocked and no fluorescence was observed.The binding specificity of Con A-FITC and Acanthamoeba cell surface mannose moieties demonstrate topographical distribution of lectin receptor sites. Ultrastructurally, ferritin-labeled Con A at cell adhesion sites showed clustering of lectin receptors. Occurrence of fluorescence in Naegleria sp. using Con A-FITC has been shown to concentrate at the uroidal region but no fluorescence was seen at the anterior of newly formed pseudopodia.