There were definitely professions that were targeted because they were felt to have insufficient class loyalty — in that they were more likely to consider themselves part of a professional class as opposed to a social class. This is probably the better equivalent for the Soviet context and the kinds of ideological anxieties that they had (which are not exactly mirrors of the US ones). An important example of this in the Stalin period was engineers — engineers were suspected of considered themselves engineers first, Soviets second. Which was not to be tolerated. The first Soviet show trial was of a group of engineers in 1922 who were accused of sabotaging the Soviet state in support of old industrialists; it set a template by which engineers in particular could be blamed for errors that could be more appropriately put at the feet of the bureaucratic state and its conditions. Interestingly, the last Soviet show trial was also of engineers being blamed for the results of their work — the Chernobyl accident trial.

There were certainly other professions that were targeted, and certainly classes of people (like the Kulaks in Ukraine), as harboring anti-Soviet sympathies as a group, or being particularly ideologically suspicious (e.g., scientists whose theories were too influenced by ideas developed in Western nations, unless very careful, could fall under ideological scrutiny, and entire areas of study, like economics, history, and sociology, needed to be entirely conformed with Soviet ideology, or risk great peril).