英语翻译Coagulase-negative staphylococci are important microorga

英语翻译
Coagulase-negative staphylococci are important microorganisms in fermented and cured meat products.While lactic acid bacteria ensure the safety of products by reducing the pH,staphylococci influence sensorial properties of meat products.They play important role in the development of aroma as well as flavour and colour of fermented products (Hugas and Monfort 1997).
Certain staphylococcal species are regularly found in ‘naturally’ processed meat products,which are produced without addition of starter cultures.However,in order to exercise greater control over the fermentations,common practices therefore involve inoculation with selected starter cultures (Miralles et al.1996).To select a suitable strain to use as starter culture not only sensorial properties are important but also the safety aspects need to be considered.Safety of these products for consumers depends on the content of biogenic amines,which might represent a food poisoning hazard (Silla 1996).Histamine is the most important biogenic amine in relation to foodborne intoxications,showing the highest biological activity and causing hypertension,hypotension,headache,nausea and vomiting (Bodmer et al.1999).
Biogenic amines may appear as a result of bacterial decarboxylation reactions from precursor amino acids.Histamine is produced by enzymatic decarboxylation of the histidine present in foods.The enzyme histidine decarboxylase (HDC) catalyses the conversion of histidine into histamine by removing the a-carboxylate group of the substrate.Two separate cofactors have been utilized to perform this decarboxylation.In some bacterial HDC the cofactor is a covalently attached pyridoxal 5-phosphate,while others utilize a covalently attached pyruvoyl moiety.Bacterial HDC have been studied and characterized in different organisms.Two enzyme families have been distinguished based on the cofactor used:the pyridoxal phosphate-dependent and the pyruvoyl-dependent,being their sequences and characteristics radically different.Pyridoxal phosphate-dependent HDC are encountered in Gram-negative bacteria belonging to various species (i.e.Raoultella planticola,Enterobacter aerogenes,Photobacterium phosphoreum,etc.) (Takahashi et al.2003; Morii et al.2006).Pyruvoyl-dependent HDCs are associated with Gram-positive bacteria and specially lactic acid bacteria implicated in food fermentation or spoilage,and they use a covalently bound pyruvoyl moiety as a prosthetic group.This pyruvoyl-dependent enzyme was reported in Lactobacillus 30a (Chang and Snell 1968),Clostridium perfringens (Recsei et al.1983),Oenococcus oeni (Coton et al.1998),Tetragenococcus muriaticus (Konagaya et al.2002),Lactobacillus buchneri (Martin et al.2005),and Lactobacillus hilgardii (Lucas et al.2005).

凝固酶阴性葡萄球菌是重要的微生物发酵和腊肉制品.而乳酸菌确保pH值降低了产品的安全性,葡萄球菌影响肉类产品的感官特性.他们发挥的香气发展的重要作用以及味道和（乌加斯和蒙福特1997）发酵产品的颜色.
某些葡萄球菌种经常发现在'自然'加工的肉类产品,是没有增加生产的发酵剂.然而,为了行使对发酵更大的控制,因此涉及共同做法与选定的发酵剂（米拉勒斯等接种.1996年）.要选择一个合适的应变作为起动文化不仅使用感官性能很重要,但安全问题也需要加以考虑.这些产品对消费者的安全取决于生物胺,这可能代表了食物中毒的危险（1996年新罗）的内容.组胺是最重要的食源性中毒有关的生物胺,显示了最高的生物活性,造成高血压,低血压,头痛,恶心和呕吐（博德默等.1999年）.
生物胺可能显示为一个由前体细菌脱羧反应的结果氨基酸.组胺是由组氨酸的食品中目前酶脱羧.这种酶组氨酸脱羧酶（HDC）催化成通过消除组胺的基板1 -羧酸组的组氨酸转化.两个独立的辅助因子已被用来执行此脱羧.在某些细菌HDC公司的辅助因子是吡哆醛5 3,6,11磷酸,而另一些利用一3,6,11 pyruvoyl基团.HDC的细菌进行了研究,并在不同的生物特征.两名杰出的酶家庭已使用的基础上,辅酶：磷酸吡哆醛的依赖和pyruvoyl依赖,被它们的DNA序列和特点截然不同.磷酸吡哆醛依赖HDC的是遇到革兰阴性菌属于不同的物种（即Raoultella planticola,产气肠杆菌,发光菌,等）（高桥等人.2003年;森井等人.2006年）.Pyruvoyl依赖HDCs都与革兰氏阳性菌和专门乳酸发酵食品中的细菌或腐败牵连,他们以此作为辅基1共价键结pyruvoyl基团.这pyruvoyl依赖性酶报告乳酸菌30A条（张斯内尔1968）,产气荚膜梭菌（雷切伊等.1983年）,酒类酒球菌（科顿等人.1998年）,四联球菌muriaticus（小长谷等人.2002年）,布氏杆菌（马丁等人.2005年）和乳酸菌hilgardii（卢卡斯等人.2005年）.