Hohl N, Galland P, Senger H
Fachbereich Biologie/Botanik der Philipps-Universität Marburg, Fed. Rep. Germany.
Photochem Photobiol. 1992 Feb;55(2):247-55. doi: 10.1111/j.1751-1097.1992.tb04234.x.
Flavins were extracted from sporangiophores of the lower fungus Phycomyces blakesleeanus and identified by HPLC with fluorescence detection. In the wild-type strain NRRL1555 they were found to be present at the following concentrations: riboflavin (5.5 x 10(-6) M), flavin mononucleotide (FMN) (4.0 x 10(-6) M) and flavin adenine dinucleotide (1.4 x 10(-6) M). The HPLC elution profiles of the wild type were compared to a set of behavioral mutants (genotype mad) with specific defects in their light-transduction pathway. The photoreceptor mutants C109 (madB), C111 (madB) and L1 (madC) had normal amounts of flavins. The most prominent changes were found in single mutants with a defective madA gene which contained about 25% of riboflavin and about 10% of FMN and FAD normally found in the wild type. A hypertropic mutant with a defective madH gene contained instead 80% of riboflavin and 120% of FMN and FAD. The double mutant L52 (madA madC) and the triple mutant L72 (madA madB madC) had normal amounts of FAD and FMN. This indicates that the madC mutation, which itself causes loss of light sensitivity and which affects the near-UV/blue-light receptor (Galland and Lipson, 1985, Photochem. Photobiol. 41, 331-335) functions as a restorer of the flavin content in a genetic madA background. The double mutant L51 (madA madB) had about 40% of FMN and FAD, suggesting that the madB mutation functions as a partial restorer of flavin content. The photogravitropic thresholds (450 nm) reported for the wild type and the madA and madH mutants were positively correlated to the endogeneous concentrations of FMN and FAD.(ABSTRACT TRUNCATED AT 250 WORDS)
从低等真菌布拉克须霉的孢子囊中提取黄素，并通过带荧光检测的高效液相色谱法进行鉴定。在野生型菌株NRRL1555中，发现它们以以下浓度存在：核黄素（5.5×10⁻⁶ M）、黄素单核苷酸（FMN）（4.0×10⁻⁶ M）和黄素腺嘌呤二核苷酸（1.4×10⁻⁶ M）。将野生型的高效液相色谱洗脱图谱与一组在其光转导途径中有特定缺陷的行为突变体（基因型mad）进行比较。光感受器突变体C109（madB）、C111（madB）和L1（madC）的黄素含量正常。在具有缺陷madA基因的单突变体中发现了最显著的变化，其核黄素含量约为野生型的25%，FMN和FAD含量约为野生型的10%。一个具有缺陷madH基因的肥大突变体的核黄素含量为80%，FMN和FAD含量为120%。双突变体L52（madA madC）和三突变体L72（madA madB madC）的FAD和FMN含量正常。这表明，madC突变本身会导致光敏感性丧失，并且会影响近紫外/蓝光受体（加兰德和利普森，1985年，《光化学与光生物学》41卷，331 - 335页），在遗传madA背景下它可作为黄素含量的恢复因子。双突变体L51（madA madB）的FMN和FAD含量约为40%，这表明madB突变可作为黄素含量的部分恢复因子。报道的野生型、madA和madH突变体的光重力阈值（450纳米）与FMN和FAD的内源性浓度呈正相关。（摘要截短于250字）
