The haloalkaliphilics are an important subset of extremophiles that grow in salt [upto 33% (wt/vol) NaCl] and alkaline pH (> 9). They are found in hypersaline environments especially in the brines in arid, coastal and deep sea locations, and in alkaline environments, such as soda soils, lakes and deserts. Some authors have described haloalkaliphilic bacteria as moderate halophilic bacteria, but the molecular and classical studies revealed that they belong to moderately to extremely halophilic bacteria and archaea. Organic solutes, such as glycine, betaine and other amino acid derivatives, sugars such as, sucrose and trehalose, and sugar alcohols present in the haloalkaliphilics help for their osmoadaptation, and also serve as stabilizers. Haloalkalphilics secrete exoenzymes like proteases, amylases, xylanases, cellulases and peroxidases which have potential industrial applications. They also produce bacteriorhodopsin, compatible solutes, pigments, biopolymers, secondary metabolites like biosurfactants, polyhydroxyalkanoate (PHA) and exopolysaccharides and antimicrobial/anticancer compounds. They have unique metabolic pathways which can be used to treat industrial pollutants, heavy metals and waste water.

中文翻译：

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卤代碱的性质和生物勘探：综述

嗜盐菌是极端微生物的一个重要子集，它们在盐 [高达 33% (wt/vol) NaCl] 和碱性 pH (> 9) 中生长。它们存在于高盐度环境中，特别是在干旱、沿海和深海地区的盐水中，以及在碱性环境中，如碱土、湖泊和沙漠。一些作者将嗜盐嗜碱细菌描述为中度嗜盐细菌，但分子和经典研究表明它们属于中度至极度嗜盐细菌和古细菌。有机溶质，例如甘氨酸、甜菜碱和其他氨基酸衍生物，糖类，例如蔗糖和海藻糖，以及卤代亲碱物质中存在的糖醇，有助于它们的渗透适应，也可用作稳定剂。嗜盐碱能分泌外酶，如蛋白酶、淀粉酶、木聚糖酶、具有潜在工业应用的纤维素酶和过氧化物酶。它们还产生细菌视紫红质、相容溶质、色素、生物聚合物、次生代谢物，如生物表面活性剂、聚羟基链烷酸酯 (PHA) 和胞外多糖以及抗微生物/抗癌化合物。它们具有独特的代谢途径，可用于处理工业污染物、重金属和废水。