Yeasts of biotechnological, taxonomic and physiological interest

An osmotolerant yeast with the rare ability to ferment D-xylose to ethanol known in fewer than 10 species. Uniquely, it also uses nitrate. This species is only distantly related to other xylose fermenters and will be useful in tracking changes among xylose fermenters. Scheffersomyces (Pichia) stipitis NRRL Y-7124 (Type) has shown substantial physiological differences from the previously sequenced strain CBS 6054 (e.g, reported xylanase activity not present in CBS 6054 and differences in cellobiose utilization). We hope to identify additional sugar transporters and understand better the regulatory differences that enable one of these two strains to ferment xylose faster, and the other to be able to ferment cellobiose faster. The yeast has a holdfast, an unusual structure in yeasts when it grows attached to the gut of wood-ingesting beetles.

一种具有渗透耐受性且罕见地将D-木糖发酵为乙醇的酵母，此种能力在不到10个物种中得以发现。尤为独特的是，该物种还能够利用硝酸盐。此物种与其它木糖发酵菌仅存在遥远的亲缘关系，对于追踪木糖发酵菌之间的变化具有重要意义。Scheffersomyces (Pichia) stipitis NRRL Y-7124（类型）与先前测序的菌株CBS 6054（例如，报告中提及的木聚糖酶活性在CBS 6054中不存在，以及纤维二糖利用上的差异）展现出显著的生理差异。我们期望识别出更多的糖转运蛋白，并更深入地理解调控差异，这些差异使得其中一种菌株能够更快地发酵木糖，而另一种菌株则能够更快地发酵纤维二糖。当该酵母附着在摄木昆虫的肠道上生长时，其具有一种独特的固着结构，这在酵母中颇为罕见。