( )不仅是EMP途径的中间产物，还是丝氨酸合成的直接前体。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='25860' and id < 2171202 and id<>'2171202' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='25860' and id > 2171202 and id<>'2171202' order by id asc limit 5