Halophiles are organisms that thrive in high salt concentrations. Lipases are important enzymes used in food, pharmaceutical, detergent and chemical industries. Enzymes perform a number of biochemical reactions, including oxidation, reduction, hydrolysis, etc. A diverse group of halophilic bacteria exist in lunsu, a. Because hucbh1 is alkaliphilic as well, it can be used in the paper, detergent and textile industries for bioremediation of cellulosic contaminants in high salt environments. Halophiles are categorized as slight, moderate, or extreme, by the extent of their halotolerance.
The role of enzymes in the fermentation process has been known for less than two hundred years. Coenzymes are heat stable low molecular weight organic compound. Thus, the ratio of acidic amino acids gluasp in the total protein sequence of a halophilic protein has been considered as an important parameter to distinguish it from nonhalophilic proteins from the same class of enzymes 39,40,41. Acidic biosensors, chiral synthesis, enzyme isoforms, halophiles. Five halophilic bacterial isolates namely ss1, ss2, ss3, ss5 and ss8 were isolated from soil sediments of lunsu, a salty water body. Moderately halophilic bacteria are a source of hydrolytic enzymes such as amylases, dnases, lipases, proteases and pullulanases. Several strains of halophilic bacteria and archaea have been isolated from such environments and characterized either by polyphasic taxonomy approach or by their ability to produce extracellular enzymes with putative potential for use in several domains like industry, agriculture and biotechnology. Genomic analysis reveals the biotechnological and industrial. Perspectives and application of halophilic enzymes. Nelson, lehninger principles of biochemistry, iv edition, w. Their enzymes are structurally adapted to perform efficient catalysis under saline environment wherein n0n halophilic enzymes often lose their structure. Enzymes have an optimum temperature at which they work fastest. Halophilic mechanisms and industrial application of enzymes from halophiles masao tokunaga, matsujiro ishibashi, hiroko tokunaga, and mayumi miyauchi applied and molecular microbiology, faculty of agriculture, kagoshima university summary we have studied halophilism of enzymes from extremely halophilic archaea and moderately halophilic bacteria. The article covers and puts in perspective the structural and biocatalytic features of.
Their enzymes are structurally adapted to perform efficient catalysis under saline environment wherein n0nhalophilic enzymes often lose their structure. Cuatrocienegas, coahuila is known for its high level of soil salinity and presence of abundant genetic variety of endemic microorganisms. Halophilic mechanisms and industrial application of. While some of the presentation may seem somewhat dated, the basic concepts are still helpful for researchers who must. Halophilic microorganisms can secrete salt and thermotolerant enzymes viz. We have studied halophilism of enzymes from extremely halophilic archaea and moderately halophilic bacteria. They are formed of protein part and non protein part. Several strains of halophilic bacteria and archaea have been. Furthermore, enzymes produced by halophilic microorganisms have an optimal function under very high salt concentrations, like kcl concentrations of. Among members of halophilic bacteria, some of them could produce extracellular protease.
Extracellular hydrolytic enzymes of halophilic bacteria. While some of the presentation may seem somewhat dated, the basic. We developed a batch process for the cultivation of h. Halophiles require sodium chloride salt for growth, in contrast to halotolerant organisms. Dec 22, 2011 a set of 15 halophilic enzymes, 9 of which from extreme halophiles and 6 from halotolerant organisms, was collected along with their non halophilic structural homologues table 1. Halophilic bacteria as a source of extracellular enzymes antonio ventosa and cristina sanchezporro department of microbiology and parasitology, university of sevilla, spain two groups of prokaryotes are adapted to live under extreme hypersaline conditions. The tetrameric forms of the halophilic malate dehydrogenase are contrasting with the usual dimeric forms of non halophilic counterparts, and this tetrameric form argues for similarity of halophilic malate dehydrogenase with non halophilic lactate dehydrogenase. Solution behavior and activity of a halophilic esterase under. Halophilic microorganisms possess stable enzymes that function in very high. The purpose of this rewiev that determination of halophilic bacteria and archaea biodegradation capacity of aromatic hydrocarbons and to clarify the metabolic pathway in this process.
Among the halophilic enzymes, 8 come from archaea that adopt the saltin strategy saltin, and 7 from eubacteria that adopt the osmolytes strategy osmol. A large number of microorganisms are found in soda lake areas of western china ma et al. Screening of halophilic lipaseproducing bacteria and characterization of enzyme for fish sauce quality improvement werasit kanlayakrit and anan boonpan abstract twenty pure bacterial cultures isolated from thai fish sauce were selected for lipase producing on sehgal and gibbons complex sgctween 80 agar containing 04 m nacl. Par ticularly, intracellular enzymes of halobacterium species have. Global nest journal, 11 173 phospholipase b plb is one of hydrolase class of enzymes that catalyzed bond breaking of two acyl chains of phospholipid. Ucd school of biomolecular and biomedical sciences conway institute university college dublin belfield, dublin 4 republic of ireland. Halophilic enzymes, while performing identical enzymatic functions as their nonhalophilic counterparts, have been shown to exhibit substantially different properties, among them the requirement for high salt concentrations, in the 14 m range, for activity and stability, and a high excess of acidic over basic amino residues. Indeed, this model cannot explain the strong dependence between salt concentration and catalytic activity of halophilic enzymes mevarech et al. This is a pdf file of an unedited manuscript that has.
Such kinds of media as salt lakes, salted soils, salt deposits or salt mines are widely distributed over the entire romanian landscape. Chemical nature of enzymes protein enzymes are classified into 2 types. Halophilic prokaryotes are adapted to thrive in extreme conditions of salinity. It is now clear that the understanding of halophilic adaptation at a molecular level requires a strategy of complementary experiments, combining molecular biology, biochemistry, and cellular approaches with physical chemistry and thermodynamics. Enzymes of halophilic archaebacteria have been attracting many researchers for many years. The methods of affinity chromatography, heat treatment, and chromatography on agarose with nh42so4 were used in the presence of high salt concentrations to purify halophilic enzymes. Frontiers protective role of salt in catalysis and. Characteristics, structural adaptation and potential applications for biocatalysis authors.
In the 1850s louis pasteur presented a theory that sugar is. Production of halophilic proteins using haloferax volcanii. Haloferax volcanii constitutes a suitable expression system for halophilic enzymes obtained from such brine pools. This invention also includes a strategy to screen halophilic enzymes for ilresistant enzymes. The function of enzymes is described as their ability to catalyse biochemical reactions according to the enzyme commission ec. Effects of salts on activity of halophilic cellulase with. While in a salt in strategy that is used primarily by haloarchaea to accumulate high concentrations of salt, their enzymes have been examined to tolerate or even require 45 m salt 41. Microbes and their enzymes have been applied for preparation of wines, beer, cheeses and other milk products. Structural adaptation of extreme halophilic proteins through. The combined form of protein and the coenzyme are called as holoenzyme.
The halotolerance of many enzymes derived from halophilic bacteria can be exploited wherever enzymatic transformations are required to function under physical and chemical conditions, such as in the presence of organic solvents and extremes in temperature and salt content. Halophilic microorganisms, either bacteria or archaea, flourish in media with salinity levels varying from negligible until to saturation in nacl and thus are considered extremophiles. Halophilic microorganisms from romanian saline environments. The emphasis was on the purification of tryptophanase and tryptophanyltrna ligase.
Notably, this is the first time that halophilic p450 enzymes has been proposed for the need of salt to. Enzymes 3d structure enzymes are proteins and their activities depends on the 3d structure of the amino acids that compose them note. Jan 10, 20 however, halophilic enzymes are active and stable in media with low water activity because even at low a w enough water is present to retain suitable charge distribution at the active site maintaining the conformation of the enzyme. A complex enzyme contains a nonprotein part, called as prosthetic group coenzymes. Aug 30, 2000 halophilic enzymes, while performing identical enzymatic functions as their nonhalophilic counterparts, have been shown to exhibit substantially different properties, among them the requirement for high salt concentrations, in the 14 m range, for activity and stability, and a high excess of acidic over basic amino residues. The halophilic organisms inhabiting under saline hypersaline conditions are considered as promising source of useful enzymes. For mammalian enzymes this is about 40c, but there are enzymes that work best at very different temperatures, e. Currently, research is focused on the halophilic and halotolerant bacteria because of their, distinctive features, like a salt tolerant proteins, highly saline cytoplasm and lightdriven proton and chloride pumps such as, bacteriorhodopsin and halorhodopsin dassarma and dassarma, 2017.
The bacterial isolates ss1 and ss3 require at least 3. Open questions 363 of the gene encoding arsm in halobacterium salinarum resulted in sensitivity to arsenite, con. Various halophilic bacteria have been isolated from small lakes in. A set of 15 halophilic enzymes, 9 of which from extreme halophiles and 6 from halotolerant organisms, was collected along with their nonhalophilic structural homologues table 1. Pdf halophilic enzymes, known as extremozymes produced by halophilic microorganisms, have identical enzymatic features like their. Halophilic and thermostable cellulases tolerant to ionic. Among these, two main points could be mentioned, i a high content in acidic. Halophilic enzymes, while performing identical enzymatic functions as their non halophilic counterparts, have been shown to exhibit substantially different properties, among them the requirement for high salt concentrations, in the 14 m range, for activity and stability, and a high excess of acidic over basic amino residues. Halophilic mechanisms and industrial application of enzymes from. Some biological reactions in the absence of enzymes may be as much as a million times slower 32. This dissertation explores aspects of the chemistry and evolution of a small class of enzymes catalysing geometrical and structural rearrangements between isomers, the. Almost all enzymes are globular proteins consisting either of a single polypeptide or of two or more polypeptides held together in quaternary structure by noncovalent bonds. While most halophiles are classified into the archaea domain, there are also bacterial halophiles and some eukaryota, such as the alga dunaliella salina or fungus wallemia ichthyophaga.
On the other hand, based on the phylogenetic classification of bacterial strains whose wgs data were available comprising of 2 extreme halophilic, 10 moderate halophilic, 15 mesophilic, and 29 nonhalophilic bacterial strains, two halophilic bacteria, elongata dsm 2581 and h. The most widespread, seen in most aerobic halophilic eubacteria as well as in halophilic archaeal methanogens, involves the synthesis or accumulation of high intracellular levels of low molecular weight organic osmotic solutes, socalled compatible solutes, such as trehalose, betaine or proline 11, 12. They function to reorganize the internal structure of the cell to regulate cellular activities. Box 5653, bucharest, romania 2halophiles research institute, 6771 shimizu, noda 2780043, japan received april 1, 2010. Halophilic mechanisms and industrial application of enzymes. The halophilic green alga dunaliella devoid of rigid cell wall builds up high intracellular glycerol concentration to maintain osmotic balance. The current report presents an extensive and systematic comparative analysis of genome and proteome composition of halophilic and non. Survival of halophiles under halophilic conditions microbiology. Enzymes may be simple proteins, or complex enzymes. Most halophilic bacteria use a salt out strategy to exclude salt to protect their nonhalophilic enzymes. Enzymes have been utilized for thousands of years in microbial processes. Salines are harsh environments where the high salt concentration precludes the survival of almost any living form but the halophilic archaea. Pdf halophilic bacteria as a source of novel hydrolytic enzymes.
Survival of halophiles under halophilic conditions. Search for new industrial enzymes having novel properties continues to be a desirable pursuit in enzyme research. These enzymes have some extra amino acids which provide an extensive negative charge on the surfaces of the enzymes danson and hough, 1997. Halophilic bacteria as a source of extracellular enzymes. The halophiles have developed a number of peculiar modifications to adapt themselves to high salty conditions. Isolasi gen fosfolipase b plb dari bakteri halofilik pseudomonas stutzeri bkab12.
Biofuels are known as the best alternatives of unrenewable fuels and justify increasing extensive research to develop new and less expensive methods for their production. Hydrolases constitute a class of enzymes widely distributed in nature from bacteria to higher eukaryotes. Frontiers halophiles and their vast potential in biofuel. Halophiles are perceived as an excellent source of novel enzymes possessing inherent ability to function under saline and hypersaline environment conditions. Perspectives and application of halophilic enzymes springerlink. It appears that halophilic archaea have adopted several strategies in order to adapt to the nutritional conditions of hypersaline environments, e. Characteristics, structural adaptation and potential applications for biocatalysis volume.
These extremophiles also are important resources to obtain novel enzymes. Our understanding of the adaptation of halophiles to high salinity. Screening of halophilic lipaseproducing bacteria and. Halophilic enzymes, known as extremozymes produced by halophilic microorganisms, have identical enzymatic features like their non halophilic counterpart, but they exhibit different properties mainly in structure.
On our previous study, we obtained four halophilic bacteria which were able to produce protease, i. Structural adaptation of extreme halophilic proteins. Halophilic enzyme activation induced by salts scientific. Review articles hydrolytic enzymes of halophilic microorganisms and their economic values madalin enache,1 masahiro kamekura2 1institute of biology bucharest of the romanian academy, splaiul independentei 296, p. In this article we will discuss about the survival of halophiles under halophilic conditions. Enzymes are responsible for the movement of ions across the plasma membrane. Enzymes do nothing but speed up the rates at which the equilibrium. Solution behavior and activity of a halophilic esterase. Organic solvents with a log p lower than 2, generally are considered to cause enzyme denaturation, producing the. Solution behavior and activity of a halophilic esterase under high salt concentration plos one, sep 2009 lang rao, xiubo zhao, fang pan, yin li, yanfen xue, yanhe ma, jian r. Moreno mdl, dolores p, maria tg, encarnacion m 20 halophilic bacteria as a source of novel hydrolytic enzymes. Global warming and the limitations of using fossil fuels are a main concern of all societies, and thus, the development of alternative fuel sources is crucial to improving the current global energy situation. Two different strategies allow halophilic organisms to cope in high salt environments 11, 12. Hypersaline environments are those with salt concentrations 910 times higher 3035% of nacl than sea water 3.
Jan 03, 2020 the purpose of this rewiev that determination of halophilic bacteria and archaea biodegradation capacity of aromatic hydrocarbons and to clarify the metabolic pathway in this process. Introduction to enzymes the following has been excerpted from a very popular worthington publication which was originally published in 1972 as the manual of clinical enzyme measurements. The report describes some of the fundamental features that stabilize halophilic, prokaryotic enzymes at salt concentrations over 1 m. Production and function of enzymes of eubacterial halophiles. Structural and biochemical characterization of several halophilic enzymes has shown that enhancing solvation is the key requirement essential for maintaining solubility and activity of halophilic enzymes in low water activity, which can approach values as low as 0. Effect of medium and environmental parameters on lipase. Extracellular hydrolytic enzymes of halophilic bacteria isolated from a subterranean rock salt crystal rom. Diversity of moderately halophilic bacteria producing extracellular. Enzymes are involved in conversion of substrate into product. Halophilic bacteria as a source of novel hydrolytic enzymes. Tryptophanyltrna ligase was purified to homogeneity and its. Halophilic enzymes, while performing identical enzymatic functions as their non halophilic counterparts, have been shown to exhibit different properties such as a requirement for high salt.
831 1215 1231 861 360 484 308 1445 1369 57 457 1324 444 759 370 849 458 668 734 720 1143 385 1442 966 1032 805 907 1099 471 727 135 917 1288 606