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Fibrillar collagen molecules are synthesized as precursors, procollagens, with large propeptide extensions. While a homotrimeric form (three α1 chains) has been reported in embryonic tissues as well as in diseases (cancer, fibrosis, genetic disorders), collagen type I usually occurs as a heterotrimer (two α1 chains and one α2 chain). Inside the cell, the role of the C-terminal propeptides is to gather together the correct combination of three α chains during molecular assembly, but how this occurs for different forms of the same collagen type is so far unknown. Here, by structural and mutagenic analysis, we identify key amino acid residues in the α1 and α2 C-propeptides that determine homo- and heterotrimerization. A naturally occurring mutation in one of these alters the homo/heterotrimer balance. These results show how the C-propeptide of the α2 chain has specifically evolved to permit the appearance of heterotrimeric collagen I, the major extracellular building block among the metazoa., Heterotrimers of collagen I (two α1 chains, one α2 chain) are crucial for the normal function of multiple tissues and organs. Here the authors show the molecular basis of both homotrimerization (three α1 chains) and heterotrimerization of collagen I through specific intermolecular interactions.

Procollagen C-proteinase enhancer-1 (PCPE-1) is a secreted protein that specifically accelerates proteolytic release of the C-propeptides from fibrillar procollagens, a crucial step in fibril assembly. As such, it is a potential therapeutic target to improve tissue repair and prevent fibrosis, a major cause of mortality worldwide. Here we present the crystal structure of the active CUB1CUB2 fragment of PCPE-1 bound to the C-propeptide trimer of procollagen III (CPIII). This shows that the two CUB domains bind to two different chains of CPIII and that the N-terminal region of one CPIII chain, close to the proteolytic cleavage site, lies in the cleft between CUB1 and CUB2. This suggests that enhancing activity involves unraveling of this chain from the rest of the trimer, thus facilitating the action of the proteinase involved. Support for this hypothesis comes from site-directed mutagenesis, enzyme assays, binding studies, and molecular modeling.

Heavy metals are among the pollutants found in urban and industrial wastewater. Various industries, such as the metal, oil and petrochemical activities are among the main sources of heavy metals discharging into the marine environment. Hormozgan province, especially Bandar Abbas City, showed significant growth in chemical industry and high urbanization rates in recent years, which could have a significant potential for heavy metals entering the coastal ecosystem. The present study aims to monitor the concentration of heavy metals (including Fe, Cu, Pb, Cd, Ni, Co) in sediments collected from East and West of Hormozgan province and assessing the status of pollutants by comparison with regional and international standards. In this research, shrimp habitats were selected on the basis of Tib, Yekshabeh, Laft and Khamir. In order to investigate heavy metals in shrimp habitats of Hormozgan province, the study was conducted seasonally from autumn 1394 to summer of 1395. Copper, Nickel, and Cobalt metals were measured by flame atomic absorption and other metals using a furnace atomic absorption device. The results of Iron measurement in sediments of sampling stations showed that maximum concentration was 1.576 mg/kg in winter at Tiab estuary, while in summer this amount was related to Khamir estuary and reached to 1.578 mg/kg. In both summer and winter, copper had the highest amount of copper in the Tiab estuary with amount of 0.377 mg / g and 0.358 mg / g, respectively. The maximum observed concentration of Nickel in Tiab estuary is 0.114 mg / kg in summer. This amount was 0.069 mg / kg for cadmium in winter in Tiab estuary sediments. Lead and Cobalt metal exhibited their maximum concentration at the same time and place with0. 403 mg / kg and 0.247 mg / kg, respectively. In general, based on the findings of this study, the average concentration of heavy metals in the surface sediments from Hormozgan estuaries was recorded as Fe> Pb> Cu> Co> Ni> Ca. The assessment of the environmental quality of the sediments for all heavy metals showed that the measured values were lower than the guidelines and none of the metals was evaluated at poluuting level. In order to protect mangrove ecosystem and control the amount of heavy metal pollution, periodic monitoring of these metals in sediments of the study area is recommended. Iranian Fisheries Science Research Institute Published

The purpose of this study was to evaluate Total petroleum hydrocarbons (TPHs) in surface sediments of Khamir, Laft, and Yekshabeh and Tiab esturies. For this purpose, sampling of surface sediments was carried out at 16 stations (four stations at each estury.In each sample, four points were taken from the beginning, the middle, the end and the junction point to the sea.The physicochemical properties of sediment such as grain size and total organic matter (TOM) were measured using standard methods. The concentration of total petroleum hydrocarbons was determined using Ultraviolet Fluorescence (UVF). Petroleum hydrocarbons showed limited variations from 53.11 to 2052.5 ng/g dry weight in the summer season and from 128.5 to.4392.5 ng/g in winter. The average detected concentrations for total hydrocarbons were lower than the environmental hazard (4000 ng/g). Most of their concentrations were observed at Yekshabeh estury in winter, possibly due to the pollution caused by the activity of ports and fishing vessels. Also, the assessment of environmental hazard caused by pollution of hydrocarbons for aquatic organisms by using SQSs and contamination coefficient (Cf) showed that the studied sediments except station 1 at Yekhshabeh estury in winter season (Cf = 0.91) has no adverse biological effects on aquatic organisms. Finally, the results of statistical analysis of the data showed that the physicochemical parameters of sediments (grain size and total organic matter (TOM)) and the total petroleum hydrocarbons were not correlated, which could indicate the existence of different sources for each studied parameters. Iranian Fisheries Science Research Institute Published

This study was conducted to compare heavy metal concentrations including lead and cadmium in liver and muscle tissues of Indian mackerel (Rastrelliiger Kanagurta) in Bandar Lengeh, Hormoz island, Hengam island and Kolahi regions. In current research, the influence of season, sex and size (length and weight) on Pb and Cd concentrations in Indian mackerel was investigated in these areas. Then Lead and cadmium concentrations in muscle tissues were compared with international standards for human consumption. Sampling was performed in summer and winter. Metal concentrations of organs were assessed by dry digestion method and atomic absorption spectrometer (AAS). Results showed that there are statistically significant differences between concentrations of lead and cadmium in liver and tissues of the fish in these regions (Bandar Lengeh, Hormoz, Hengam and Kolahi) (p0.05). In addition, there is no correlation between lead and cadmium concentrations in muscle and liver of Indian mackerel with size (length and weight) (p>0.05).

In the present study, accumulation of manganese, cadmium, zinc, iron and copper in the commercially fish species (silver pomfret and tiger tooth croaker) caught from Bandarabbas coasts at 2010 was measured and the risk of daily intake of them in Hormozagan urban population was estimated. The average concentrations (µ/g dry weight) of manganese, cadmium, zinc, iron, and copper in the muscle tissue of silver pomfret were 1.248, 0.217, 14.444, 2.397 and 3.300, respectively, while the concentration of them in tiger tooth croaker were 1.009, 0.403, 12.564, 4.467 and 2.366, respectively. According to fish consumption rate, urban populations of the province were divided into four groups; low, medium, high and very high. The target hazard quotient (THQ) in each group calculated separately. The THQ of all groups were much lower than 1 in the two fish. The results showed that urban populations of the province have not any risk due to accumulation of the studied heavy metals.

Survey on physicochemical parameters and pollutants in artificial reefs in Hormozgan province (Bandar-e-Lengeh area) was conducted during 2004-2007. After establishing of artificial reefs by Hormozgan Shilat office, selection of sampling stations is performed at summer and winter seasons. Summer and winter values for temperature were 32.9 0.5 and 21.4 0.5 centigrade. pH had a little range of tolerance (8-8.95) and its annual mean was 8.81 0.13 . Transparency is an effective parameter on monitoring of artificial reefs. Summer and winter values for Transparency were 3.8 3.72 and 5.63 0.78 meters. Annual mean of dissolved oxygen and salinity were 7.11 0.1 ppm and 39.13 0.26 ppt. Annual means of dissolved nitrate, nitrite and orthophosphate were 4.9 0.7, 1.44 0.09 and 0.97 0.06 micromole per liters respectively. Measurement of chl.a was done in summer only. The maximum concentration was 2.95 microgram per liter. Annual average percentage of silt, clay and sand were 33 10.68, 21.63 4.84 & 45.96 12.66 respectively. Organic Carbon percentage had a little rang (0.61 1.92) of changes. Its annual percentage was 0.99 0.2. Summer and winter values for COD were 1.53 0.48 & 1.62 0.48 milligrams per liter. Concentration of heavy metals (Cu, Zn, Fe, Ni & Pb) in sediments were determined .All of heavy metals (especially Pb) had higher concentration in summer than winter. The annual means of Cu, Zn, Fe, and Ni & Pb were 26.5, 54.3, 27.6, 70.85 & 48.15 micrograms per gram of dried sediment. Normal aliphatic hydrocarbons (C10-C 30) were determined in water & sediment. Annual average and the summer and winter values for normal aliphatic hydrocarbons in water were 258.7, 217.8 & 299.6 micrograms per liter and for sediment were 5726.8, 12616.8 & 2132.2 micrograms per gram of dried sediment.

This project was carried out from November 2008 for about two years. Seven laboratories of the research center including: Chromatography, Instrumental Analysis, Aquatic zoology, Sample preparation, Histology, Plankton and Benthos were selected for the accreditation. The quality manual of the test laboratories was written following the general requirements of ISO/IEC 17025. During the establishment of the system standardization of the test methods, calibration of the equipment, test methods validation, uncertainty estimation of measurement and update and improvement of physical conditions of the laboratories were performed. The technical and quality management competence of the laboratories were evaluated by the auditors from DGA (the German Accreditation System for Testing Laboratories), which is signatory of ILAC (International Laboratory Accreditation Co-operation). The laboratories officially accredited by DGA, after the successful completion of the accreditation process (including implementation of corrective actions for the detected nonconformities). The accreditation is valid from 2009-11-12 to 2014-11-11. Production of reliable results of the test methods from national and international scientific organizations' point of view as well as facilitation in development of bilateral and multilateral relations with them can be considered as the advantages of the system establishment. Moreover, exchange of the relevant scientific information and experiences among the researchers will be facilitated. Iranian Fisheries Science Research Institute Published

This project was carried out from November 2008 for about two years. Seven laboratories of the research center including: Chromatography, Instrumental Analysis, Aquatic zoology, Sample preparation, Histology, Plankton and Benthos were selected for the accreditation. The quality manual of the test laboratories was written following the general requirements of ISO/IEC 17025. During the establishment of the system standardization of the test methods, calibration of the equipment, test methods validation, uncertainty estimation of measurement and update and improvement of physical conditions of the laboratories were performed. The technical and quality management competence of the laboratories were evaluated by the auditors from DGA (the German Accreditation System for Testing Laboratories), which is signatory of ILAC (International Laboratory Accreditation Co-operation). The laboratories officially accredited by DGA, after the successful completion of the accreditation process (including implementation of corrective actions for the detected nonconformities). The accreditation is valid from 2009-11-12 to 2014-11-11. Production of reliable results of the test methods from national and international scientific organizations' point of view as well as facilitation in development of bilateral and multilateral relations with them can be considered as the advantages of the system establishment. Moreover, exchange of the relevant scientific information and experiences among the researchers will be facilitated.